DE102023116506B4 - force sensor - Google Patents

Abstract

The invention relates to a force sensor comprising: an active layer, wherein an electrical variable of the force sensor depends on a force acting on the active layer in such a way that a change in the force acting on the active layer causes a change in the electrical variable; wherein the force sensor comprises an attachment which is arranged relative to the active layer in such a way that a force acting externally on the force sensor is guided to the active layer by means of the attachment. The invention further relates to a sensor group, an assembly, a set for positioning sensors on opposite regions of a head, a sensor cap for receiving at least one sensor, and uses and methods using the force sensor.

Description

TECHNICAL FIELD

The invention relates to a force sensor, a sensor group with two force sensors, an assembly with a force sensor and a further sensor, a set with at least one force sensor for positioning on a head, a sensor cap for receiving at least one force sensor and uses and methods for applying these components, in particular for patients.

BACKGROUND

Force sensors with different basic technologies are known.

The printed matter US 2013/0 085 400 A1 describes the following: Non-invasive intracranial pressure detection and/or monitoring and related use of data. Regarding a method, there may be, for example, a method for digitally generating and transmitting intracranial pressure data from electrical skull deformation signals, the method comprising: receiving sensed electrical skull deformation signals from at least one sensor at electrical equipment configured to convert and process the received skull deformation signals; converting and processing the received electrical skull deformation signals by the electrical equipment to generate digital intracranial pressure data; and outputting the digital intracranial pressure data by the electrical equipment via an output device operatively connected to the electrical equipment to represent the digital intracranial pressure data. US 2003/0 191 410 A1 describes a method for determining diastolic intracranial pressure (ICP) in a patient. A first change in the length of a path across the patient's skull, caused by a known change in ICP, is measured and used to determine an elastic constant for the patient. A second change in the length of the path across the patient's skull, occurring between the systolic and diastolic portions of the patient's heartbeat, is then measured. The patient's diastolic ICP is a function of the elastic constant and the second change.

The printed matter US 2018/0 353 122 A1 describes a device and method for detecting and reducing bruxism. The method involves placing a pressure-sensitive (or piezoelectric) sensor on the skin above the temporalis muscle to detect teeth grinding based on the movement of the temporalis muscle. Alternatively, a pressure resistor in the ear could be used. The pressure resistor sensor could be made of carbon-impregnated polyolefin. Once bruxism is detected, the patient is notified and can use biofeedback to limit teeth grinding.
Further state of the art: US 2022 / 0 183 656 A1 , US 2013 / 0 018 277 A1 , US 2015 / 0 359 457 A1

SUMMARY OF THE INVENTION

The inventors have recognized that it can be useful for patients to position one or more force sensors on the patient's body in order to use the force sensors to non-invasively detect forces occurring on the body. Through this non-invasive detection of such forces, movements or expansions of muscles, veins, the skull, or other areas of the body can be determined without major interventions. The inventors have recognized that for such applications on a patient's body, which is sometimes difficult to access and sometimes constantly and not always uniformly moving, the force sensors of the prior art are not sufficient to reliably detect such forces occurring on the body.

It is therefore the object of the present invention to provide a force sensor that can detect forces more reliably.

This object is achieved with a force sensor according to main claim 1. The force sensor according to the invention is for detecting forces occurring on a head and comprises: an active layer, wherein an electrical variable (e.g. electrical resistance or electrical voltage) of the force sensor depends on a force acting on the active layer in such a way that a change in the force acting on the active layer causes a change in the electrical variable; an attachment arranged relative to the active layer in such a way that a force acting externally on the force sensor is guided to the active layer by means of the attachment (e.g. through the attachment); and a wafer for supporting the active layer and the attachment, wherein the attachment is arranged between the active layer and the wafer, or wherein the active layer is arranged between the attachment and the wafer. The fact that the force sensor comprises an attachment arranged relative to the active layer in such a way that a force acting externally on the force sensor is introduced to the active layer by means of the attachment increases the reliability of the force detection. The essay provides contributes to the force acting on the force sensor reaching the active layer.

The attachment is beneficial for introducing the force to be detected onto the active layer: The attachment and its aforementioned arrangement relative to the active layer can increase the probability that the force to be detected will also be introduced onto the active layer. For example, conditions surrounding the force sensor may make it impossible to reliably introduce the force to be detected directly onto the active layer, whereas the attachment with the aforementioned arrangement relative to the active layer still allows the force to be detected to be introduced onto the active layer by acting on the attachment. This allows the force to be detected to be detected more reliably. The attachment is particularly advantageous in areas of a patient's body that are sometimes difficult to access, as the body is sometimes constantly and not always moving uniformly.

Additionally, the attachment reduces the probability that forces to be detected in areas outside the active layer or the active surface of the active layer will not act on the active layer. In this respect, the attachment focuses the forces that occur. This also increases the reliability of the detection of the forces to be detected.

According to a preferred aspect of the force sensor according to the invention, the attachment can rest on a surface (e.g., the active area) of the active layer, which can be particularly effective with regard to the above-mentioned advantages of the attachment. This surface can be, for example, on a front or back side of the active layer. The attachment can be attached, preferably detachably, to the force sensor or to the active layer using a fastening means (e.g., a film or an adhesive such as an adhesive film).

In addition, the attachment reduces the force sensor's susceptibility to interference, thereby further increasing the reliability of force detection. In a force sensor environment with a wide range of movements, particularly around a patient's body (the patient rarely remains completely still), constant movement creates disruptive forces from a variety of sources that can interfere with the detection of the actual force. The attachment and its aforementioned positioning relative to the active layer can reduce the likelihood that undetectable forces will also be transmitted to the active layer. For example, the attachment can be positioned so that the desired rather than the undesired forces are detected.

According to a preferred aspect of the force sensor according to the invention, a first cross-section through the attachment can have a larger cross-sectional area than a second cross-section through the attachment, wherein the second cross-section is further away from the active layer and/or an active surface of the active layer than the first cross-section. In other words, the attachment can be tapered in a direction leading away from the active layer and/or the active surface of the active layer. Due to this configuration of the shape of the attachment, the attachment can have a selective effect on the forces such that the area to which the detected force on the force sensor originally couples is smaller than the active layer or the active surface of the active layer. Thus, the region in which occurring forces are detected can be further limited and thus the above-described susceptibility to interference due to the detection of unwanted forces can be further reduced.

The object is further achieved by a sensor group according to the invention, comprising: a first force sensor according to the invention and a second force sensor according to the invention, wherein the first force sensor and the second force sensor are electrically connected in parallel. By connecting the resistors of the two force sensors in parallel, the sensitivity of the force detection can be increased, which also contributes to the reliability of the force detection. By connecting the resistors of the two force sensors in parallel, the change in the detected force is amplified by the total resistance of the individual resistors of the force sensors connected in parallel.

Preferably, an assembly according to the invention is further provided, comprising: a force sensor according to the invention; a further sensor which is designed to transmit and/or receive a signal via an active sensor surface of the further sensor; wherein the force sensor is attached to a side surface of the further sensor, preferably opposite the active sensor surface, such that the attachment, in particular its second side surface, faces away from the side surface of the further sensor. By arranging the force sensor and the further sensor in the assembly, the measurements with the further sensor and the measurements with the force sensor can be carried out in parallel and in the same spatial area. Thus, effects (for example, movements or expansions on the patient's body) which are related to the force to be detected can be qualitatively taken into account during the measurement with the further sensor. This can make these measurements more precise and/or meaningful. For example, the additional sensor can be an ultrasound probe used to perform ultrasound measurements, for example, on the patient's skull. During these ultrasound measurements, movements or expansions of the patient's body, which are detected by the force sensor, can be qualitatively taken into account in the evaluation of the ultrasound measurements.

In connection with patients, it may be desirable to attach one or more of the force sensors according to the invention, either alone or in combination with another sensor (or more), to a body part, such as a head, of a patient and to detect forces occurring there.

In previous approaches, sensors were attached to the head with a band, such as a headband, to conduct a diagnostic examination on the body part. Such a band has an elastic band that can be applied circumferentially to the body part. Due to the elasticity of the band, a restoring force of the band causes the band to be pressed against the body part in a circumferential area and fixed thereto. In the case of a head, the headband is preferably applied to a forehead area, a rear area, and opposite lateral areas of the head above the ears. Furthermore, one or more sensor caps have often been provided on the band, which are designed in such a way that they each have an opening on two opposite sides for the headband to pass through. The band and the sensor caps are configured in such a way that the sensor caps, with the sensors located therein, are pressed against the body part by the band between the band and the body part. This allows the sensor caps and the sensors to be held and positioned on the body part.

However, such solutions using bands have proven disadvantageous for certain, particularly medical, examinations on the head for several reasons, while bands or other supports can be used for other detections on the head or for examinations on other parts of the body.

Firstly, it is difficult to position the sensor caps with the sensors reproducibly on the head of the same patient. In the case of head injuries, a parameter of the head is observed on the same patient over an extended period of time. For this purpose, measurements are taken on the head of the same patient at intervals in order to determine how the condition develops over time. For this purpose, the headband must be removed from the patient's head several times and then put back on for a new measurement. In this case, it may not be possible to reproduce the sensor position from a previous measurement in a subsequent measurement. This inaccuracy or lack of reproducibility of the sensor positions falsifies the measured values of the series of measurements for certain examinations and can lead to medical misjudgment.

Furthermore, the positioning of the sensors on the head has proven to be too inaccurate for certain examinations, as the position of the sensors along the headband and the position of the headband on the head can vary. This results in the alignment of the sensors being too inaccurate for certain examinations, making it impossible to adjust the sensor field of observation with sufficient precision.

Second, the sensors cannot be coupled to the head effectively enough for certain examinations. The headband transmits a uniform contact pressure to the entire circumference of the head. This means that only a small portion of the contact pressure is applied to the sensors, and a higher contact pressure than is normally necessary must be set to couple the sensors. This is particularly disadvantageous in cases of head injuries.

In addition, the contact pressure depends on the adjustment of the headband, which means that the contact pressure can vary between different measurements, which is disadvantageous when comparing the measured values for specific examinations.

Furthermore, the use of such a headband has proven disadvantageous for certain examinations, as it requires the patient's head to be lifted to apply the headband. Lifting the head is undesirable, especially in cases of head injuries, as it can cause further injury and pain to the patient or interfere with life-sustaining therapies (e.g., a ventilation tube).

The inventors have discovered that reproducible positioning of the sensors at defined areas on the head has a major influence on the results of such examinations.

• - ein oder mehrere erfindungsgemäße Kraftsensoren;
• - ein Kopfbügel, der ausgelegt ist, den Kopf zumindest teilweise zu umlaufen;
• - an gegenüberliegenden Bereichen des Kopfbügels angeordnete Sensorkappen, die ausgelegt sind zur Aufnahme von jeweils mindestens einem der Kraftsensoren; und
• - ein mit dem Kopfbügel verbundener Nasenbügel, der ausgelegt ist, den Kopfbügel auf einem Rücken der Nase des Kopfes zu lagern. Zwei oder mehr Sensoren verbessern das Signal-to-Noise Ratio, jedoch sind die hier beschriebenen Aufbauten auch mit nur einem Kraftsensor möglich.

Therefore, according to the invention, a set for positioning sensors on opposite areas of a head is preferably also provided, the set comprising:

• - one or more force sensors according to the invention;
• - a headband designed to at least partially encircle the head;
• - sensor caps arranged on opposite areas of the headband, each designed to accommodate at least one of the force sensors; and
• - A nosepiece connected to the headband, designed to rest the headband on the ridge of the nose. Two or more sensors improve the signal-to-noise ratio, but the setups described here are also possible with just one force sensor.

Against the background described above, the set according to the invention makes it possible to overcome the disadvantages of the headband, at least for certain examinations, and in particular to be able to carry out non-invasive diagnostic examinations better on a patient's head.

The headband and its attached sensor caps determine the position of the sensors on the head. The positioning of the sensor caps on opposite parts of the headband ensures that the sensors in the sensor caps are positioned on opposite parts of the head, thus ensuring that they are symmetrically positioned on the head and preferably aligned with each other.

The nosepiece, which is connected to the headband, supports the headband on the bridge of the nose. This allows the position of the headband and the attached sensor caps to be aligned with a predefined reference point on the patient's head, i.e., the nose. Using the inventive assembly, sensors can be positioned more precisely at predetermined positions on the head.

Furthermore, the reference point improves the reproducibility of the areas on the head where the sensors are applied, as the reference point, i.e., the position of the nose, does not change for a patient. Furthermore, the position of the reference point, i.e., the nose, on the head is very similar for different patients with similar head sizes, thus enabling reproducibility of the sensor positions between patients of similar head sizes.

Furthermore, the inventors have discovered that the pressure applied to the head by the sensors often has a further major influence on the results of diagnostic examinations.

According to the inventive set, the contact pressure with which the sensors in the sensor caps rest on the head is essentially determined by the headband. Since the head diameter does not change for an individual patient and the position of the sensors on the head is reproducible, the contact pressure of the sensors on the head is easily reproducible between individual examinations. Furthermore, the head diameters for a class of patients (e.g., children or adults) are at least similar, so the contact pressure is at least similar for different patients within a class.

Furthermore, the use of such a headband has proven particularly effective in practice for patients with head injuries. A headband can be applied to the head from one side. Applying the headband no longer necessarily requires lifting the patient's head, which is advantageous for patients with a head injury.

In addition to the force sensors, further sensors can be incorporated into the sensor caps, e.g., one force sensor and one further sensor per sensor cap. The further sensor can, for example, comprise an emitter for outputting signals and/or a detector for receiving output signals. Based on the interaction of the signals with the head, conclusions can be drawn about a parameter of the head, in particular within the skull. In some aspects, an emitter is positioned on one side of the head and a detector is positioned on an opposite side of the head to detect the emitted signals through the head. In other aspects, an emitter and a detector can each be positioned on one side of the head.

The inventive set has proven particularly useful for the exemplary application of non-invasive determination of intracranial pressure. For determining intracranial pressure, the sensors comprise an emitter as a sensor for emitting ultrasound signals and a detector as a sensor for receiving the emitted ultrasound signals. The sensors can be positioned on opposite regions of the head using the set. Based on the transit time of the ultrasound signals through the head, the intracranial pressure can be classified.

Further preferred aspects of the set are explained below.

According to a preferred aspect, the nose clip is connected to the headband in a region of the headband approximately centrally between the sensor caps.

This relative arrangement of the headband adapts the headset to the anatomy of the head, ensuring that the sensor caps are symmetrically aligned on the head in opposing areas. This is especially true because the nose is positioned approximately centrally on the face in one area. By positioning the nosepiece approximately centrally between the sensor caps on the headband, the headband is centered on the head.

According to a preferred aspect, the headband at least partially surrounds an axis in a first plane running perpendicular to the axis, wherein the nosepiece intersects the first plane, preferably in a direction approximately perpendicular to the first plane.

This arrangement allows the relative positioning of the headband and nosepiece to be particularly effectively adapted to the anatomy of the head when the headband partially encircles the head and the nosepiece rests on the bridge of the nose.

In some particularly preferred aspects, the nose bridge can extend from the headband in a direction approximately perpendicular to the first plane. For example, the nose bridge can be formed approximately coaxially with the direction approximately perpendicular to the first plane.

According to these aspects, the headband encircles the head approximately in a frontal region, preferably in a forehead region, with the nosepiece resting on the bridge of the nose. This leaves an upper half of the head free for other medical measuring devices or invasive devices for treating an injury.

In this aspect, the length of the nose bridge can be made particularly short, which improves the stability of the set, especially of the nose bridge.

According to a preferred aspect, the nose bridge has an end piece at an end opposite the headband, wherein the end piece has a preferably approximately bow-shaped indentation aligned approximately along the axis, which is designed to prevent a relative movement of the nose bridge to the bridge of the nose in a direction parallel to a frontal plane of the head and parallel to the first plane.

Such an end piece reduces relative movement of the assembly relative to the head. This improves the stability of the assembly's alignment on the head. This reduces the possibility of the assembly shifting position on the head.

According to a preferred aspect, the nose bridge has a length of 2 cm - 7 cm, preferably about 5 cm or less, starting from the connection to the headband.

In particularly preferred embodiments, the length of the nosepiece is measured in a direction approximately transverse to the first plane between the approximately central region of the headpiece between the sensor caps and a region of the nosepiece which, according to the application, rests on the bridge of the nose.

The length of the nose bridge determines, at least in part, the positioning of the headband and thus of the sensor caps on the head. The inventors discovered that this design of the nose bridge particularly closely mirrors the head anatomy of a large number of patients. The sensors can therefore be positioned at predetermined positions on the head for the vast majority of patients.

According to a preferred aspect, the sensor caps have a distance of 10 cm - 17 cm, 11 cm - 16 cm or about 13 cm from the nose bridge.

In some particularly preferred embodiments, the distance along the headband between a sensor cap and the nosepiece is measured.

The distance between the sensor caps and the nosepiece determines the positioning of the sensor caps on the head relative to the position of the nose. The inventors have further discovered that this headpiece design specifically reflects the anatomy of the head of a large number of patients for positioning the sensor caps on the head. Thus, the sensor caps can be positioned at the specified positions on the head for the vast majority of patients.

For example, the headband can be designed so that it can be placed approximately parallel to a transverse plane of the head, so that the sensor caps are arranged in an area approximately above the ear canal on opposite areas of the head. In particular In preferred aspects, the headband can be configured such that a sensor cap is arranged in a region between the T3 position and the T5 position, preferably at a distance of 3.5-4.5 cm from the T3 position, and a sensor cap is arranged between the T4 and T6 position, preferably at a distance of 3.5-4.5 cm from the T4 position. In particular, one sensor cap can be arranged in each region of the fascia of the temporalis muscle.

According to a preferred aspect, each sensor cap comprises a preferably approximately cylindrical recess for receiving a sensor, which recess has an opening on one side and is at least partially delimited by the sensor cap on a bottom side of the sensor cap opposite the opening and on at least one side surface of the sensor cap.

In use, a sensor is inserted through the opening in the sensor caps into the recess in the sensor caps. After insertion, a sensor is positioned in the recess of a sensor cap. The sensor is then exposed on one front side through the opening in the sensor cap, allowing the front of the sensor to rest directly against the head. On the other sides, the sensor is at least partially surrounded by the sensor cap, allowing it to be held in the sensor cap and pressed against the head by the sensor cap.

In particularly preferred aspects, a depth of the recess from the opening to the bottom side is dimensioned such that a sensor inserted into the recess protrudes at least partially beyond an edge of the sensor cap surrounding the opening.

This allows the pressure exerted on the head by the headband to be focused on the sensors in the sensor caps.

According to a preferred aspect, the openings of the sensor caps face each other.

According to this aspect, sensors arranged in the recesses of the sensor caps located on opposite areas of the head are aligned with each other. Since the sensors in the sensor caps are directly in contact with the head through the openings, it can be ensured that signals emitted and detected by the sensors travel directly through the head to the respective opposite sensor without passing through further sections, for example, the sensor cap.

According to a preferred aspect, the sensor cap has, at a preferably approximately central position on the bottom side, a preferably approximately hemispherical elevation directed in the direction of the opening, which represents a stop and/or adjustment aid for a sensor.

According to this aspect, the orientation of the sensor can adapt to a surface of the head so that the sensor rests optimally against the surface of the head. A sensor located in the recess is pressed against the head by the sensor cap connected to the headband. The protrusion forms a stop for a rear side of the sensor facing away from the head. Thus, a sensor strikes the protrusion in a partial area of the rear side, with the remaining areas of the rear side that do not strike the protrusion being exposed towards the bottom by the protrusion. This allows the sensor to adapt its orientation so that this plane rests against the head when pressure is exerted on the front of the sensor by a surface of the head.

According to a preferred aspect, each sensor cap has at least one through-opening into the recess through the at least one side surface, wherein the through-opening opens into the opening of the recess via a through-opening region.

For example, a sensor can communicate with a processing unit via a sensor cable to exchange signals. The sensor cable can be connected to the sensor or connectable to it. A sensor has a front side configured to rest against a head and a rear side opposite the front side. The cable can protrude from the sensor in a direction approximately perpendicular to a direction perpendicular to the front side and the rear side.

When a sensor connected to a sensor cable is inserted through the opening of the recess into the sensor cap, the sensor cable can be inserted through the feedthrough area into the feedthrough opening at the same time as the sensor is inserted into the recess. This advantageously guides the sensor cable away from the sensor in the recess through the sensor cap. Furthermore, the cable is at least partially circumferentially limited by the sensor cap, thereby limiting the sensor's mobility in the recess.

For example, this prevents twisting in the direction perpendicular to the front and back.

According to a preferred aspect, the feedthrough region has a taper relative to a diameter of the feedthrough opening.

When a sensor connected to a sensor cable is inserted into the recess while simultaneously passing the sensor cable connected to the sensor through the feedthrough area into the feedthrough opening, the sensor cable overcomes the taper by exerting a force. When the sensor is positioned in the recess and the sensor cable is in the feedthrough opening, the taper prevents the sensor cable from sliding out of the feedthrough opening via the feedthrough area. This prevents a sensor connected to the sensor cable from sliding out of the sensor cap's recess.

According to a preferred aspect, each sensor cap has a further opening which at least partially exposes the recess through the at least one side surface and/or through the bottom side.

According to this aspect, a sensor arranged in the recess is at least partially exposed laterally and/or at its rear side through the further opening of the sensor cap surrounding the sensor. The areas of the sensor exposed by the further opening are thus accessible from outside the sensor cap. This makes it easier to remove a sensor from the recess in the sensor cap.

According to a preferred aspect, each sensor cap has a further recess for receiving a magnet on a side opposite the opening of the recess.

The sensors can preferably be paramagnetic, preferably having a paramagnetic backing. By positioning a magnet on the side of the sensor cap opposite the opening of the recess, the magnet and the sensor cap are attracted to each other by a magnetic force, so that a force acts on the sensor toward the bottom side and the sensor is held in the recess of the sensor cap.

According to a preferred aspect, the fitting comprises a magnet which can be fastened to one of the sensor caps, preferably in the further recess.

According to a preferred aspect, such a magnet can be attached to the back of the sensor cap via an approximately clamp-shaped holder. According to a preferred aspect, the magnet can be secured in the further recess, for example, by means of an adhesive or a cover covering the further recess.

According to a preferred aspect, the set comprises at least three preferably clip-shaped markers which can be attached to different areas on the nose bridge, the headband and/or the sensor caps.

These markers are detectable in various imaging techniques. This allows the positioning of the clothing relative to the head to be represented in an image of the head with the clothing.

For example, the markers are designed so that they are visible in an MRI (magnetic resonance imaging) scan of the head with the headpiece. This makes the positioning of the headpiece visible in the MRI scan. This allows the examined areas of the head to be linked to spatial planes of the MRI scan.

In addition, a three-dimensional view of the visible area of a head with the headgear can be captured. Such a view can preferably be captured and created using a stereo camera or a camera from different perspectives.

In a further step, the three-dimensional view of the head with the headgear in the visible range and the MRI image of the head with the headgear can be superimposed using the markers. This allows information to be obtained about the positioning of the headgear and the areas of the head traversed by the signals.

According to a preferred aspect, the markers each have a marker body made of the same material as the nose bridge, the headband and/or the sensor caps.

Preferably, the marker body, the nose bridge, the headband and the sensor caps can be made of the same material.

The material in the marker bodies makes the markers and their bodies more easily distinguishable from the set in an MRI scan. This allows for the positioning of the set and its components. the sensors are determined three-dimensionally on the head.

According to a preferred aspect, the fitting further comprises at least one preferably approximately disc-shaped pad which can be attached to one of the sensor caps and/or the headband and has a hole such that, when the pad is attached to the sensor cap and/or the headband, the hole is aligned with the opening of the sensor cap such that a sensor arranged in the recess of the sensor cap rests over or through the opening and over or through the hole on the head or scalp. The edge of the hole of the pad can completely enclose or surround the opening of the sensor cap; for example, the outer diameter of the opening can be smaller than the inner diameter of the hole. The hole and/or opening can be circular. Preferably, the pad can be releasably attached to one of the sensor caps and/or the headband, for example by means of an adhesive. Preferably, the pad is designed to adhere to the scalp, for example by means of an adhesive.

Such a pad is designed to fit between the head and the sensor cap. The hole in the pad exposes a sensor located in the recess of the sensor cap. The pad can be glued to the sensor cap and/or the sensor bracket, for example.

Such a pad improves the adhesion of the sensor cap to the head. This reduces the risk of the device shifting position on the head. The pad preferably has a relatively high coefficient of friction with the head, particularly the scalp. Furthermore, the pad can be elastically designed so that it is compressed by force exerted by the head and the sensor cap, allowing the sensor to rest against an area of the head. Such a pad can be made of silicone, for example.

According to a preferred aspect, the pad preferably protrudes beyond lateral edges of the sensor cap and has a gap through which a portion of the head or scalp can be marked when the pad is attached to the sensor cap and/or the headband.

When the headgear is in contact with the head with such a pad, an area of the head exposed by the gap can be marked. The markings remain visible even after the headgear has been removed, allowing the headgear to be reattached to the same position on the head after removal.

According to a preferred aspect, the headband comprises: a curved section which preferably runs approximately semicircularly around the axis in the first plane; two approximately rectilinear sections, each of which merges into the curved region at a first end and at whose opposite second end a sensor cap is located; wherein the two approximately rectilinear sections converge towards one another starting from the respective first end.

This aspect ensures that the contact pressure exerted by the headband is focused on the sensor caps and the sensors contained therein.

According to a preferred aspect, the approximately rectilinear sections each enclose an angle of 75°-85°, 77°-83° or approximately 80° with a second plane oriented perpendicular to the first plane through the first ends of the two approximately rectilinear sections.

The inventors have discovered that such an angle ensures that a sufficient contact pressure can be achieved for a large number of patients while avoiding the headband from touching the head, while the headband runs approximately semicircularly between the respective first ends.

According to a preferred aspect, the headband is elastically designed, preferably as a bending spring.

The fitting can, for example, be designed such that a diameter measured between the opposing sensor caps is smaller than a transverse diameter of the head, preferably in a region above the ear canals.

The elasticity and the associated restoring force of the headband ensure that the headband presses the sensor caps and the sensors contained therein against the sides of the head. This allows the headset to be secured to a patient's head, at least temporarily.

According to a preferred aspect, the headband, the nosepiece, and the sensor caps are preferably formed integrally from the same material. In other preferred aspects, designs are also possible in which the headband, the nosepiece, and the sensor caps are made of different parts and/or different made of different materials and can be fixed to one another.

This ensures sufficient rigidity of the assembly to prevent changes in the position of the sensor caps between individual measurements.

The assembly is preferably designed such that the relative positions of the sensor caps, headband, and nosepiece cannot be changed between individual measurements. This means that the positions of the sensor caps, headband, and nosepiece are consistent at least between individual measurements. For this purpose, according to a preferred aspect, the sensor caps, headband, and nosepiece are formed as a single piece or at least can be fixed to one another.

According to a preferred aspect, the material is a biocompatible material, preferably a polyamide PA12, particularly preferably PA2200.

Biocompatible material doesn't trigger toxicological processes. This makes it comfortable to wear and relatively lightweight. This material is particularly advantageous if the headgear is worn for extended periods.

In addition, such a material is suitable for performing MRI measurements on the head with the headgear on, as it has no magnetic or paramagnetic properties.

In further aspects, a particularly advantageous sensor cap for positioning sensors on a head is provided.

According to a preferred aspect, a sensor cap is provided for receiving at least one sensor, the sensor cap comprising: a preferably approximately cylindrical recess for receiving a sensor, the recess having an opening on one side and being at least partially delimited by the sensor cap on a bottom side of the sensor cap opposite the opening and on at least one side surface of the sensor cap.

Such a sensor cap is designed to accommodate a sensor in the recess. A front side of the sensor is exposed through the opening so that the front side can rest against a patient's head. The sensor is delimited and held in position by the bottom side and at least one side surface in the recess.

According to a preferred aspect, the sensor cap has, at a preferably approximately central position on the bottom side, a preferably approximately hemispherical elevation directed in the direction of the opening.

When the front of the sensor is placed against a surface of the head, the sensor can adapt its orientation to the surface of the head.

According to a preferred aspect, the sensor cap has a through-opening into the recess through the at least one side surface, wherein the through-opening opens into the opening of the recess via a through-opening region.

When a sensor connected to a sensor cable is inserted through the opening of the recess into the sensor cap, the sensor cable can be inserted through the feedthrough area into the feedthrough opening at the same time as the sensor is inserted into the recess. This advantageously guides the sensor cable away from the sensor in the recess through the sensor cap. Furthermore, the cable is at least partially circumferentially limited by the sensor cap, thereby limiting the sensor's mobility in the recess. For example, this prevents twisting in the direction perpendicular to the front and back.

According to a preferred aspect, the feedthrough region has a taper relative to a diameter of the feedthrough opening.

The tapered section holds a sensor cable connected to the sensor in the feedthrough opening. This allows a sensor connected to the sensor cable to be held in the recess.

According to a preferred aspect, the sensor cap has a further opening which at least partially exposes the recess through the at least one side surface and/or through the bottom side.

The areas of the sensor exposed by the wider opening are accessible from outside the sensor cap. This makes it easier to remove the sensor from the recess in the sensor cap. It also facilitates heat dissipation from the sensor. improved because these areas are not surrounded by the sensor cap.

According to a preferred aspect, the sensor cap has a further recess with a magnet on a side opposite the opening of the recess.

By positioning a magnet on the side of the sensor cap opposite the opening of the recess, the magnet and the sensor cap are pulled towards each other by a magnetic force, so that a force acts on the sensor towards the bottom side and the sensor is held in the recess.

Furthermore, the object mentioned at the outset is achieved by a method for producing the previously described fitting or for producing a sensor cap, the method comprising the production of the fitting or the sensor cap by means of 3D printing.

With this manufacturing process, both the set and the sensor cap can be manufactured particularly efficiently and individually for each patient. In particular, 3D printing allows the set and the sensor caps to be manufactured particularly effectively as a single piece.

Furthermore, the object is achieved by using the initially described fitting, comprising the steps of: inserting at least one sensor into a recess of a sensor cap; positioning the fitting on the head such that the sensors in the sensor caps rest on opposite sides of the head and the nosepiece rests on the bridge of the nose.

By using such a set, sensors arranged in the sensor caps can be applied to the opposite areas of the head for a measurement.

According to a preferred aspect, inserting at least one sensor into a recess of a sensor cap comprises: During insertion of the at least one sensor into the recess of a sensor cap, passing a sensor cable connected to the sensor through the feedthrough area into the feedthrough opening in order to engage the cable through the taper.

This allows a sensor to be held in the recess of the sensor cap.

According to a preferred aspect, inserting at least one sensor into a recess of a sensor cap comprises: inserting the at least one sensor into the recess of a sensor cap until a rear side of the sensor strikes the bottom side or the elevation.

The stop on the elevation allows the sensor to adjust its orientation under the influence of pressure exerted on the sensor by the head.

According to the invention, a sensor cap for receiving at least one sensor is also provided, the sensor cap comprising: a force sensor according to the invention; a preferably approximately cylindrical recess for receiving the force sensor, wherein the recess has an opening on one side and is at least partially delimited by the sensor cap on a bottom side of the sensor cap opposite the opening and on at least one side surface of the sensor cap.

The force sensor according to the invention, the sensor group according to the invention, the assembly according to the invention, the fitting according to the invention and the sensor cap according to the invention can be used particularly advantageously for detecting a carlot movement of a skull.

A computer-assisted method according to the invention for detecting a carlot movement of a skull of a head by means of a fitting according to the invention arranged on the head can comprise: detecting an electrical signal generated by means of the electrical quantity of at least one of the force sensors; and detecting the carlot movement based on the detected electrical signal.

A further computer-assisted method according to the invention for determining a physiological parameter of a patient by means of at least one force sensor according to the invention arranged on a region of a body part, preferably a vein such as an artery, can comprise: detecting an electrical signal generated by the electrical quantity of the force sensor; and determining the physiological parameter based on the detected electrical signal.

A further computer-aided method according to the invention for generating a control signal for a software application by means of a fitting according to the invention arranged on a body part, preferably a head, can comprise: detecting a pattern in an electrical signal generated by means of the electrical quantity of at least one of the force sensors; and in response to that detects patterns, generating a control signal for a function of the software application.

In the following, further properties, features and advantages of the invention will become clear by describing preferred embodiments of the invention with reference to the accompanying exemplary drawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS

• 1 A to C show examples of force sensors according to the invention with differently shaped attachments.
• 2 A to B show examples of force sensors according to the invention with attachments placed at different locations relative to the active layer.
• 3 A shows an example of a sensor group according to the invention in a set according to the invention, as well as a measuring apparatus.
• 3 B to C show examples of the measurements taken with the measuring apparatus according to 3 A measurement results obtained.
• 4 shows an example of an assembly according to the invention comprising a force sensor according to the invention and a further sensor
• 5 A shows an example of a force sensor according to the invention in a measuring apparatus.
• 5 B shows an example of the measurement equipment according to 5 A measurement results obtained.
• 6 shows an example of a perspective view of a set.
• 7 shows an example of a top view of a set.
• 8 shows an enlarged view of a sensor cap as an example.
• 9 shows an example of a perspective view of a set with markers.

The features disclosed in the above description, the figures and the claims may be important both individually and in any combination for the realization of the invention in the various embodiments.

Reference symbols in the figures refer to the same elements.

DETAILED DESCRIPTION OF THE INVENTION

1 and 2 show exemplary preferred implementations of the force sensor 1000 according to the invention.

As can be seen from the figures, the force sensor 1000 comprises an active layer 1001, wherein an electrical quantity of the force sensor 1000 depends on a force F acting on the active layer 1001 in such a way that a change in the force acting on the active layer 1001 causes a change in the electrical quantity. The force sensor 1000 further comprises an attachment 1002, which is arranged relative to the active layer 1001 in such a way that a force acting externally on the force sensor 1000 is guided by means of the attachment 1002 (e.g. through the attachment) to the active layer 1001. The attachment therefore contributes to the force F acting on the force sensor 1000 reaching the active layer 1001. The force sensor also comprises a 1 wafer (not shown) for carrying the active layer and the attachment. This wafer 1003 is in 2 shown in more detail.

The active layer 1001 may have an active area 1001a, wherein the electrical quantity of the force sensor may depend on the force F acting on the active area 1001a in such a way that a change in the force acting on the active area causes the change in the electrical quantity.

The force sensor 1000 preferably has a first side surface 1002b, which faces the active layer 1001 and/or the active surface 1001a of the active layer 1001. Preferably, the attachment 1002 can rest with the first side surface 1002b on the active layer 1001 or on the active surface 1001a of the active layer 1001. The attachment 1002 can have a second side surface 1002a, which faces away from the active layer 1001 and/or the active surface 1001a of the active layer 1001. As in 1A to C As shown, the force F to be detected can act on the attachment 1002 via the second side surface 1002a, wherein this force is introduced via the first side surface 1002b onto the active layer 1001 or its active surface 1001a and causes a change in the electrical quantity there.

As in the 1B and 1C As shown, a first cross-section through the cap 1002 may have a larger cross-sectional area than a second cross-section through the cap, wherein the second cross-section is farther away from the active layer 1001 and/or the active area of the active layer 1001 than the first cross-section. Alternatively or additionally, the cap 1002 may be tapered in a direction leading away from the active layer 1001 and/or the active area of the active layer 1001.

The attachment 1002 can be cuboid ( 1A) , truncated cone or prism-shaped ( 1B) , or hemispherical ( 1C ) be.

The attachment can be attached, directly or indirectly, to the active layer 1001.

The force sensor 1000 can be designed such that, upon an increase in the force acting on the active layer 1001 (or active area 1001a), the electrical quantity (e.g., electrical resistance or electrical voltage) decreases, preferably continuously and/or proportionally; and/or the force sensor 1000 can be designed such that, upon a decrease in the force acting on the active layer 1001 (or active area 1001a), the electrical quantity increases, preferably continuously and/or proportionally. For example, the force sensor can be a transimpedance converter, such as the Force Sensing Resistor (FSR) from Interlink Electronics. The force sensor 1000 of the type described herein allows for providing a high-ohmic resistance in the unloaded state, enabling exponential changes in the electrical quantity (e.g., resistance), has no cross-sensitivity, and enables improved introduction of the force onto the sensor (e.g., force focusing) to be achieved without a complicated mechanical structure.

The force sensor 1000 can be designed such that in an unloaded state of the active layer 1001, an electrical contact of the force sensor 1000 is interrupted and that the electrical contact is closed by the force acting on the active layer 1001 in order to make the change in the electrical quantity measurable as a function of the change in the force F acting on the active layer 1001 (or active surface 1001a).

2 shows an example of a preferred internal structure of the force sensor 1000 according to the invention, in particular of the active layer 1001.

The active layer 1001 of the force sensor 1000 can comprise a first substrate 1004 and a second substrate 1006, which are spaced apart from one another in the unloaded state of the active layer 1001 (e.g., by a spacer 1005 arranged therebetween, such as an adhesive layer), thereby interrupting the electrical contact. The two substrates 1004, 1006 can be arranged such that the substrates 1004, 1006 come into contact with one another due to the force F acting on the active layer 1001, thereby closing the electrical contact. Preferably, the force acting on the active layer 1001 can act on the active surface 1001a of the active layer 1001, wherein the active surface 1001a forms a surface of the first substrate 1004 (as exemplified in 2 shown) or the second substrate 1006.

The attachment can rest on a surface (e.g., the active area 1001a) of the active layer 1001. This surface can be, for example, on a front or a back side of the active layer. For example, the attachment can rest on the surface (e.g., the active area 1001a) of the first substrate 1004 or on the surface (e.g., the back side of the active layer) of the second substrate 1006. The attachment can be attached, preferably detachably, to the force sensor or to the active layer 1001 using a fastening means (e.g., a film or an adhesive such as an adhesive film).

The attachment 1002 can be designed to focus the force F acting externally on the force sensor 1000 onto the active layer 1001 and/or the active surface 1001a of the active layer 1001.

The force sensor 1000 further comprises a wafer 1003 for supporting the active layer 1001 and the attachment 1002, as shown in 2 The wafer contains electrodes for tapping an electrical quantity (e.g., a voltage) that depends on the force F.

Preferably, the active layer 1001 is arranged between the attachment 1002 and the wafer 1003 ( 2 A) The attachment 1002 is then arranged on the front side of the active layer 1001. In this way, the force F to be detected can act from the outside by means of the attachment 1002 (here: through the attachment) on the active layer 1001 or its active surface 1001a. Preferably, the second substrate 1006 can be arranged between the first substrate 1004 and the wafer 1003, and the first substrate 1004 can be arranged between the attachment 1002 and the second substrate 1006.

Alternatively or additionally, the attachment 1002 may be arranged between the active layer 1001, in particular the second substrate 1006, and the wafer 1003 on the back side of the active layer 1001 ( 2 B) In this case, a force acting on the force sensor from the outside, in particular outside the active area 1001a, can still reach the active layer by way of a counterforce, which is then caused by the attachment 1002 on the back of the active layer 1001, and there preferably cause an electrical contact between the two substrates 1004 and 1006. For example, electrical contacts can also be present on the substrate 1006, which are higher than the active area. The attachment 1002 then compensates for this height difference. 2B In the manner of arranging the attachment 1002 as shown, a force acting externally on the force sensor can act on the active layer 1001 or its active surface 10001a by means of the attachment.

The wafer 10003 and/or the attachment 1002 have a stabilizing effect on the force sensor and in particular on its substrates 1004 to 1006. For example, the upper 1005 and/or lower substrate 1006 of the force sensor can be flexible (e.g., a foil 1005, 1006), which can cause the force sensor to bulge. The wafer and/or the attachment prevent such bulging in both arrangements according to 2A and 2B .

Preferred for the arrangements according to 2 A and B is the attachment 1002 made of a rigid material.

In 2 An example is the cuboid shape of the attachment 1002 from 1A However, all information related to the 2 The features of the force sensor described can also be realized with an attachment 1002 having another of the shapes described here, for example the shape according to one of the 1B or 1C has.

3 A shows an example of a sensor group 1000-1, 1000-2 according to the invention in a set 1 according to the invention, as well as a measuring apparatus. 3 B to C show examples of the measurements taken with the measuring apparatus according to 3 A measurement results obtained.

3A shows, by way of example, the use of a set according to the invention with a sensor group in a measuring apparatus. The sensor group comprises: a first force sensor 1000-1 according to the invention and a second force sensor 1000-2 according to the invention. Preferably, the first force sensor 1000-1 and the second force sensor 1000-2 are electrically connected in parallel to increase their sensitivity. The electrical resistance of the first force sensor 1000-1 can be electrically connected in parallel with an electrical resistance of the second force sensor 1000-2.

The sensors 1000-1, 1000-2 are connected to the sensor housing 1 by means of the inventive set 1, which is described further below in 6 to 9 described, each fixed to opposite sides of a patient's head 1040 (see 3A) The assembly fulfils the following tasks: fixing the force sensors at the measuring points T3 and T4 of the head and generating a contact pressure so that the force sensors are subjected to a preload.

The force sensors are used here to record the movement or expansion of the calottes. Since the calotte moves rhythmically in synchrony with the blood flow, this movement can be recorded qualitatively. 3 A shows schematically the expansion ΔS of the calotte, whereby the expansion can be most pronounced at the measuring points T3 and T4 of the head.

Due to the expansion ΔS, a force ΔF acts on the force sensors 1000-1, 1000-2. Each sensor 1000-1, 1000-2 changes its resistance R proportional to the force ΔF, which is converted into a voltage by an electronic circuit, which is then amplified (circuit and/or transimpedance amplifier 1010). The output of this amplifier 1010 represents a voltage U, which is digitized in converter 1020 (e.g., XTDC) and subsequently visualized and/or evaluated in a data processing unit 1030. 3 B shows an example of the voltage U over time t and its normalized frequency spectrum. The dominant frequency corresponds to 1 Hz, which corresponds to a heartbeat of 60 beats per minute.

If you look at 3 C a single pulse from the voltage curve in 3B , the course of the spherical cap movement can be qualitatively tracked from the voltage change. As the force F acting on the force sensor increases due to the spherical cap movement, the electrical resistance R of the force sensor decreases, and depending on the specified circuit, this is accompanied by a corresponding decrease or increase in the voltage U that is detected. Conversely, as the force F acting on the force sensor decreases with the spherical cap movement, the electrical resistance R of the force sensor increases, and depending on the specified circuit, this is accompanied by a corresponding increase or decrease in the voltage U that is detected.

Accordingly, a computer-assisted method for detecting a calotte movement of a skull of a head by means of a fitting 1 according to the invention arranged on the head can comprise the following operations: detecting an electrical signal generated by means of the electrical quantity of at least one of the force sensors 1000-1, 1000-2; and detecting the calotte movement based on the detected electrical signal.

4 shows an assembly according to the invention. The assembly 100 comprises: a force sensor 1000 according to the invention; a further sensor 102, which is designed to transmit and/or receive a signal via an active sensor surface 101 of the further sensor 102; wherein the force sensor 1000 is arranged on a side surface, preferably opposite the active sensor surface 101 of the further sensor 102 is mounted such that the attachment 1002, in particular its second side surface 1002a, faces away from the side surface of the further sensor 102.

The further sensor 102 can be a transmitter and/or a receiver of the signal. Preferably, the further sensor 102 is an ultrasonic probe, wherein the signal is an ultrasonic signal. This assembly 100 can be used instead of the two force sensors 1000-1, 1002 in 3 be installed in the fitting or its sensor caps in order to qualitatively track the calotte movement in 3B and 3C are carried out in parallel and essentially at the same location as the ultrasound measurements taken through the patient's head in order to qualitatively take the skull movement into account when evaluating the ultrasound measurement and thus make it more meaningful.

5A shows a measurement setup with at least one force sensor 1000 according to the invention, which is applied to an area 1050 of a patient's body part in order to detect a force ΔF there. This area 1050 can be a vein or a muscle, or another area of the body part. The force sensor 1000 can be integrated, for example, into a wristband, chest strap, collar, headband, or the inventive accessory. The sensor can also be held manually against the area 1050.

Sensor 1000 changes its resistance R proportionally to the force ΔF, which is converted into a voltage by an electronic circuit, which is then amplified (circuit and/or transimpedance amplifier 1010). The output of this amplifier 1010 represents a voltage U, which is digitized in converter 1020 (e.g., XTDC) and subsequently visualized and/or evaluated in a data processing unit 1030.

5 B shows an exemplary curve of the voltage U over time t and its normalized frequency spectrum. 5B shows measurement results in which the force sensor according to the invention was held to an artery (carotid artery) and the data U was recorded, whereby periodic force changes were also qualitatively detected. The dominant frequency in the frequency spectrum of the 5B corresponds to 1 Hz, which corresponds to a heartbeat of 60 beats per minute.

Accordingly, a computer-assisted method according to the invention for determining a physiological parameter of a patient by means of at least one force sensor 1000 arranged at a region 1050 of a body part, preferably a vein such as an artery, may comprise the following operation: detecting an electrical signal generated by the electrical quantity of the force sensor 1000; and determining the physiological parameter based on the detected electrical signal.

Preferably, the force sensor 1000 can be arranged on the region 1050 in such a way that a force caused by the region 1050 (e.g., the wire) acts via the attachment 1002 on the active layer 1001 of the at least one force sensor 1000.

The reliable detection of forces or changes in forces in the human body can be used for a variety of applications, particularly in the field of patient care. For example, the force sensor 1000 according to the invention can be applied to a muscle in the head region of a patient in order to detect, for example, teeth clenching. From these detected forces or changes in forces due to muscle activity when teeth are clenched, specific signal patterns can be generated in control signals to control a function in a software application. Such a function can control switching on, switching off, starting a communication, ending a communication, or any other function of a software application from a patient's everyday life. This enables patients, especially paralyzed or otherwise disabled people, to participate in everyday life, even if, for example, their arms and/or legs cannot be moved. Thus, solely based on muscle activity, for example in the head, the patient can send signals to their environment and exercise control.

Accordingly, a computer-assisted method according to the invention for generating a control signal for a software application by means of one or more force sensors 1000, 1000-1, 1000-2 according to the invention or assembly 1 according to the invention arranged on a body part, such as the head, can comprise the following operations: detecting a pattern in an electrical signal generated by means of the electrical quantity of at least one of the force sensors 1000, 1000-1, 1000-2; and in response to the detected pattern, generating a control signal for a function of the software application. Preferably, different detected patterns can correspond to control signals of different functions of the software application. At least one of the force sensors 1000-1, 1000-2 can preferably be arranged on the head, preferably by means of assembly 1, in such a way that a force caused by a movement of a muscle on the head acts on the active layer 1001 of the at least one force sensor 1000-1, 1000-2 via the attachment 1002.

The method may further comprise: converting the electrical variable of the at least one force sensor 1000-1, 1000-2 into the electrical signal by means of an electrical circuit 1010, preferably wherein the electrical variable is an electrical resistance and the electrical signal is an electrical voltage signal. Preferably, the electrical signal can be converted into a digital signal by a digital converter 1020, which is evaluated and/or visualized by a data processing unit 1030.

6 shows an example of an embodiment of a set 1 according to the invention including one or more force sensors 1000 according to the invention (not shown here). The set 1 serves to position the one or more force sensors 1000, as well as possibly a further sensor 102 (e.g. assembly 100), on opposite areas of a head, as is also shown in 3 A , 4 or 5 A can be used to position the one or more sensors 102, 1000 on the head.

The set 1 comprises a headband 2, which at least partially surrounds an axis A in a first plane running perpendicular to the axis A. At opposite ends of the headband 2 there are two sensor caps 3, each for receiving at least one sensor 102 and/or 1000, e.g. the assembly 100. The sensor cap 3 can receive an assembly 100, e.g. an assembly 100 as in 4 shown. The active sensor surface 101 of the further sensor 102 can rest on the surface of the head, while the attachment 1002 of the force sensor 1000 can rest on the bottom side 8 or the elevation 10 of the set 1 (cf. 8 ). In this way, the measurement can be carried out particularly effectively with the additional sensor 102 on the head, while the force sensor 1000 detects a force acting on the active layer 1001 from the set 1 via the attachment 1002.

Furthermore, the set 1 comprises a nose bridge 4, which extends from an approximately central region between the sensor caps 3 in a direction approximately perpendicular to the headband 2. The nose bridge 4 has, at an end opposite the headband 2, a preferably bow-shaped end piece 5 for receiving the bridge of the nose of a head.

The headband 2 is dimensioned such that the sensor caps 3 are positioned on opposite areas of the head, preferably in an area between the T3 and the T5 position in the 10-20 system and in an area between the T4 and the T6 position in the 10-20 system on the head, when the headband 2 at least partially encircles the head and the nosepiece 4 with the end piece 5 is mounted on the back of the nose.

According to a preferred aspect, a distance between the sensor caps 3 is smaller than a transverse diameter of the head, preferably measured between the area between the T3 and T5 position and the area between the T4 and T6 position in the 10-20 system.

Furthermore, the headband 1 is elastically formed, preferably in one piece, so that the sensor caps 3 with sensors 102, 1000 located therein are pressed laterally against the opposite areas of the head.

The sensor caps 3 are each designed to accommodate an approximately cylindrical sensor 102, 1000 or cylindrical assembly 100. To accommodate such a sensor 102, 1000, a sensor cap 3 has a recess 6, which is delimited in the direction of the head by an opening 7 and is delimited by the sensor cap 3 on a side surface 9 of the sensor cap 3 that at least partially surrounds the recess, and is delimited by the sensor cap 3 on a bottom side 8 of the sensor cap 3 opposite the opening 7.

The opening 7 is designed so that a sensor 102, 1000 can be inserted through it into the recess 6. A sensor 102, 1000 arranged in the recess 6 is then exposed through the circumferential opening 7 in the direction of the head, so that a front side of the sensor 102, 1000 can rest against the head, with the sensor 102, 1000 being laterally delimited by the side surface 9 of the sensor cap 3 and the bottom side 8 of the sensor cap 3. The sensor 102, 1000 is thus held in the sensor cap 3 when the fitting 1 rests against the head.

In the example shown, the openings 7 of the two sensor caps 3 face each other. The sensors 102, 1000 arranged in the recesses 6 can thus be aligned with each other.

Furthermore, a sensor cap 3 has at least one, preferably two, through-openings 11 through the side surface of the sensor cap 3 for a sensor cable connected to the sensor. A through-opening is designed to lead a sensor cable connected to the sensor out of the sensor cap laterally through the sensor cap.

The two through-holes 12 can be spaced apart in the circumferential direction. This allows different radial orientations of the sensors 102, 1000 in the recess 6.

A feedthrough opening 11 opens into the opening 7 of the sensor cap 3 via a feedthrough area 12. The feedthrough area 12 and the feedthrough opening 11 are designed such that a sensor cable connected to the sensor 102, 1000 can be pushed from the opening 7 through the feedthrough area 12 into the feedthrough opening 11 when the sensor 102, 1000 is pushed through the opening 7 into the recess 6. The sensor cable connected to the sensor is thus guided laterally through the sensor cap 3 away from the sensor 102, 1000.

The sensor cable is at least partially circumferentially limited by the sensor cap 3, whereby the sensor 102, 1000 is held in position.

The through-hole 11 has a taper 13 relative to a diameter of the through-hole 11, so that a sensor cable cannot slide directly through the through-hole area 12 from the through-hole 11 toward the opening 7. This allows a sensor 102, 1000 connected to the sensor cable to be fixed in the recess 6.

Furthermore, a sensor cap 3 has a further opening 14, which at least partially exposes the recess 6 through the side surface 9 of the sensor cap 3 and the bottom side 8 of the sensor cap 3. This at least partially exposes a sensor 102, 1000 arranged in the recess 6.

7 shows a top view of set 1 in 6 .

The headband 2 has a curved section 16 that at least partially encircles the axis A in the first plane. The curved section 16 is preferably semicircular. Furthermore, the headband 2 has two approximately rectilinear sections 17 that extend in the first plane. The two approximately rectilinear sections 17 each merge into the curved section 16 at a first end and each terminate in a sensor cap 3 at a second end opposite the first end.

In the plan view it can be seen that the two approximately rectilinear sections 17 converge towards each other starting from the respective first end in the first plane.

From the top view it can be seen that a distance measured between the sensor caps 3 is smaller than a radial diameter of the curved region 16 measured between the first ends of the respective approximately rectilinear sections 17.

As a result, the contact pressure exerted on the head is focused on the sensor caps 3 or on the sensors 102, 1000 in the sensor caps 3.

8 shows a perspective view of a sensor cap 3 of the 6 or 7 set shown 1.

It is shown that the sensor cap 3 has an approximately cylindrical recess 6, which is delimited on one side by a circumferential opening 7 and, on a side opposite the opening 7, by a bottom side 8 of the sensor cap 3 and laterally by a circumferential side surface 9 of the sensor cap 3. The recess 6 thus formed in the sensor cap 3 serves to accommodate a sensor 102, 1000.

Furthermore, the sensor cap 3 has on the bottom side 8 an approximately hemispherical elevation 10 directed in the direction of the opening, which forms a stop for a sensor 102, 1000.

When a sensor 102, 1000 strikes the approximately hemispherical elevation 10 with a rear side in a first region, a region of the rear side of the sensor surrounding the first region is spaced from the bottom side 8 of the sensor cap 3. If a compressive force is exerted by the head toward the bottom side on the sensor 102, 1000, the sensor 102, 1000 can thus adjust its orientation within the recess 6.

In addition, the feedthrough openings 11 are visible through the side surface 9 of the sensor cap 3, which open into the opening 7 via the feedthrough area 12.

The feedthrough area 12 has a taper 13. The taper 13 is formed by opposing areas of the sensor cap 3, which are spaced apart by a distance less than the diameter of the feedthrough opening 11.

To form a taper, the opposite lateral areas of the sensor cap can have a bevel in the direction of the opening 7 so that the sensor cable can be guided more easily from the opening 7 in the direction of the through-hole 12 into the through-hole 12 when inserted into the through-hole 11 through the through-hole area 12.

In addition, a further recess 14 of the sensor cap 3 can be seen, which at least partially exposes the recess 6 through the bottom side 8 of the sensor cap 3 and the side surface 9 of the sensor cap 3.

9 shows a perspective view of a set 1 in combination with markers 15.

The markers 15 are approximately clip-shaped and can be attached to various areas of the set 1. The markers 15 are preferably made of the same material as the set 1.

In some examples, one marker 15 can be attached to an approximately central region of the nose bridge 4, and at least two additional markers 15 can be attached to different regions of the headband 2. In further examples, the at least two markers 15 can each be attached to a side of a sensor cap 3 facing away from the head. In further examples, multiple markers 15 can be attached to different regions of the assembly 1, on the sensor caps 3, on the headband 2, and on the nose bridge 4.

The markers 15 are particularly visible in an MRI scan of the head with the set 1 attached, so that the position of the set 1 can be set in relation to information about the head in the MRI scan.

While features of various aspects or embodiments of the invention have been described above by way of example, so that those skilled in the art can better understand the present invention, it is to be understood that other aspects and embodiments than those described in detail may also be subject to the invention, the invention being defined by the scope of the appended claims.

List of reference symbols:

1

set

2

Headband

3

Sensor caps

4

nose bridge

5

end piece

6

recess

7

opening

8

bottom side

9

side surface

10

Survey

11

Feed-through opening

12

Implementation area

13

rejuvenation

14

Further opening

15

marker

16

Curved section

17

Straight section

A

axis

100

module

101

active sensor area

102

additional sensor

1000, 1000-1, 1000-2

force sensor

1001

active layer

1001a

active area

1002

Essay

1002a

second side surface

1002b

first side surface

1003

wafers

1004

first substrate

1005

spacers

1006

second substrate

1010

Circuit with amplifier if necessary

1020

Digital converter

1030

data processing unit

1040

body part

1050

area of a body part

Claims (36)

Force sensor (1000) for detecting forces occurring on a head, comprising: an active layer (1001), wherein an electrical quantity of the force sensor (1000) is determined by a force acting on the active layer (1001) depends on the fact that a change in the force acting on the active layer (1001) causes a change in the electrical quantity; wherein the force sensor (1000) comprises an attachment (1002) which is arranged relative to the active layer (1001) in such a way that a force acting externally on the force sensor (1000) is guided to the active layer (1001) by means of the attachment (1002); characterized in that the force sensor further comprises: a wafer (1003) for carrying the active layer (1001) and the attachment (1002), wherein the attachment (1002) is arranged between the active layer (1001) and the wafer (1003), or wherein the active layer (1001) is arranged between the attachment (1002) and the wafer (1003). The force sensor (1000) after Claim 1 , wherein the force sensor (1000) is designed such that when the force acting on the active layer (1001) increases, the electrical quantity decreases, preferably continuously and/or proportionally; and/or wherein the force sensor (1000) is designed such that when the force acting on the active layer (1001) decreases, the electrical quantity increases, preferably continuously and/or proportionally. The force sensor (1000) according to one of the preceding claims, wherein the force sensor (1000) is designed such that in an unloaded state of the active layer (1001) an electrical contact of the force sensor (1000) is interrupted and that the electrical contact is closed by the force acting on the active layer (1001) in order to make the change in the electrical quantity measurable as a function of the change in the force acting on the active layer (1001). The force sensor (1000) after Claim 3 , wherein the active layer (1001) comprises a first substrate (1004) and a second substrate (1006) which are spaced apart from one another in the unloaded state of the active layer (1001) and thereby interrupt the electrical contact, wherein the two substrates (1004, 1006) are arranged such that the substrates (1004, 1006) come into contact with one another due to the force acting on the active layer (1001) and thereby close the electrical contact. The force sensor (1000) after Claim 4 , wherein the force acting on the active layer (1001) acts on an active surface (1001a) of the active layer (1001), wherein the active surface (1001a) is a surface of the first substrate (1004) or the second substrate (1006). The force sensor (1000) according to one of the preceding claims, wherein the attachment (1002) has a first side surface (1002b) facing the active layer (1001) and/or the active surface of the active layer (1001), and wherein the attachment (1002) has a second side surface (1002a) facing away from the active layer (1001) and/or the active surface of the active layer (1001), preferably wherein the attachment (1002) is designed to conduct the force acting externally on the force sensor (1000) via the second side surface (1002a), through the attachment (1002), and via the first side surface (1002b) onto the active layer (1001) and/or the active surface (1001a) of the active layer (1001). The force sensor (1000) according to any one of the preceding claims, wherein a first cross-section through the attachment (1002) has a larger cross-sectional area than a second cross-section through the attachment, wherein the second cross-section is further away from the active layer (1001) and/or the active area of the active layer (1001) than the first cross-section. The force sensor (1000) according to one of the preceding claims, wherein the attachment (1002) tapers in a direction away from the active layer (1001) and/or the active surface of the active layer (1001). The force sensor (1000) according to one of the preceding Claims 4 until 8 , wherein the attachment (1002) is arranged between the second substrate (1006) and the wafer (1003). The force sensor (1000) according to one of the preceding Claims 4 until 8 , wherein the second substrate (1006) is arranged between the first substrate (1004) and the wafer (1003) and the first substrate (1004) is arranged between the attachment (1002) and the second substrate (1006). A sensor group comprising: a first force sensor (1000-1) according to any one of the preceding claims and a second force sensor (1000-2) according to any one of the preceding claims, wherein the first force sensor (1000-1) and the second force sensor (1000-2) are electrically connected in parallel with each other. An assembly (100) comprising: a force sensor (1000) according to one of the preceding Claims 1 until 10 ; a further sensor (102) which is designed to transmit and/or receive a signal via an active sensor surface (101) of the further sensor (102); wherein the force sensor (1000) is attached to a side surface of the further sensor (102), preferably opposite the active sensor surface (101), in such a way that the attachment (1002), in particular its second side surface (1002a), faces away from the side surface of the further sensor (102). The assembly (100) according to Claim 12 , wherein the further sensor (102) is an ultrasonic probe, and wherein the signal is an ultrasonic signal. Set (1) for positioning sensors on opposite areas of a head, the set (1) comprising: - one or more force sensors (1000, 1000-1, 1000-2) each according to one of the preceding Claims 1 until 10 ; - a headband (2) which is designed to at least partially surround the head; - sensor caps (3) arranged on opposite regions of the headband (2), which are each designed to receive at least one of the force sensors; and - a nose clip (4) connected to the headband (2) which is designed to support the headband (2) on a ridge of the nose of the head. Set according to Claim 14 wherein each of the force sensors is received in a different one of the sensor caps arranged on opposite regions of the headband such that a force exerted by the head on the force sensor (1000) acts via the attachment (1002) on the active layer (1001) of the force sensor. Set according to Claim 14 or 15 , wherein the set comprises a first assembly (100) which includes the first of the force sensors (1000-1), wherein the set comprises a second assembly (100) which includes a second of the force sensors (1000-2), and wherein each of the two assemblies (100) comprises a further sensor (102) which is designed to transmit a signal via an active sensor surface (101) of the further sensor (102) in the direction of the head and/or to receive it from the direction of the head, and wherein in each of the assemblies (100), the respective force sensor (1000) is attached to a side surface of the respective further sensor (102), preferably opposite the active sensor surface (101), in such a way that the attachment (1002) of the respective force sensor (1000-1, 1002-2), in particular its second side surface (1002a), is detachably connected to the side surface of the respective further sensor (102). Set according to Claim 16 , wherein the sensor caps (3) arranged on opposite areas of the headband (2) are designed to each accommodate at least one of the assemblies (100) together with its respective further sensor (102). The set according to Claim 16 or 17 , wherein in each of the assemblies (100) the further sensor (102) is an ultrasonic probe and the signal is an ultrasonic signal. Set according to one of the previous Claims 14 until 18 , wherein the force sensors (1000-1, 1000-2) are electrically connected in parallel with one another and/or wherein the electrical resistances of the force sensors (1000-1, 1000-2) are electrically connected in parallel. Set according to one of the previous Claims 14 until 19 , wherein the nose bridge (4) is connected to the headband (2) in a region of the headband (2) approximately centrally between the sensor caps (3). Set according to one of the previous Claims 14 until 20 , wherein the headband (2) at least partially surrounds an axis (A) in a first plane running perpendicular to the axis (A), and wherein the nosepiece (4) intersects the first plane, preferably in a direction approximately perpendicular to the first plane. Set (1) according to one of the previous Claims 14 until 18 , wherein the nose bridge (4) has an end piece (5) at an end opposite the headband (2), wherein the end piece (5) has a preferably approximately bow-shaped indentation aligned approximately along the axis (A), which is designed to prevent a relative movement of the nose bridge (4) to the bridge of the nose in a direction parallel to a frontal plane of the head and parallel to the first plane. Sensor cap (3) for receiving at least one sensor, the sensor cap (3) comprising: a force sensor (1000) according to one of the preceding Claims 1 until 10 ; a preferably approximately cylindrical recess (6) for receiving the force sensor (1000), wherein the recess (6) has an opening (7) on one side and is at least partially delimited by the sensor cap (3) on a bottom side (8) of the sensor cap (3) opposite the opening (7) and on at least one side surface (9) of the sensor cap (3). Sensor cap (3) after Claim 23 , wherein the sensor cap comprises an assembly (100) including the force sensor (1000), and wherein the assembly (100) comprises a further sensor (102) configured to transmit a signal via a active sensor surface (101) of the further sensor to transmit and/or receive and wherein in the assembly (100) the force sensor (1000) is attached to a side surface of the respective further sensor (102), preferably opposite the active sensor surface (101), in such a way that the attachment (1002) of the force sensor (1000), in particular its second side surface (1002a), faces away from the side surface of the further sensor (102). The set according to any of the Claims 14 until 22 or the sensor cap Claim 23 or 24 wherein each force sensor (1000) or assembly (100) is arranged in one of the sensor caps or in the recess of the sensor cap. Use of a force sensor (1000) according to one of the Claims 1 until 10 , a sensor group (1000-1, 1000-2) according to Claim 11 , an assembly (100) according to Claim 12 or 13 , a set (1) according to one of the Claims 14 until 22 or Claim 25 , or a sensor cap (3) according to one of the Claims 23 until 25 to detect the movement of a skull's dome. Computer-assisted method for detecting a calotte movement of a skull of a head by means of a set (1) arranged on the head according to one of the Claims 14 until 22 or Claim 25 , the method comprising: detecting an electrical signal generated by the electrical quantity of at least one of the force sensors (1000-1, 1000-2); and detecting the calotte movement based on the detected electrical signal. The procedure according to Claim 27 , where the electrical signal is a periodic electrical signal and the cap movement is detected by a change in the amplitude of the periodic electrical signal. The procedure according to Claim 27 or 28 , wherein the at least one force sensor (1000-1, 1000-2) is arranged on the head by means of the fitting such that a force caused by the calotte movement acts via the attachment (1002) on the active layer (1001) of the at least one force sensor. The procedure according to Claim 29 , wherein the electrical signal correlates with the force caused by the dome movement such that a change in the force caused by the dome movement causes a change in the amplitude of the electrical signal. Computer-assisted method for determining a physiological parameter of a patient by means of at least one force sensor (1000) arranged on a region (1050) of a body part, preferably an artery, of the patient according to one of the Claims 1 until 10 , the method comprising: detecting an electrical signal generated by the electrical quantity of the force sensor (1000); and determining the physiological parameter based on the detected electrical signal. The procedure according to Claim 31 , wherein the force sensor (1000) is arranged on the region (1050) in such a way that a force caused by the region (1050) acts via the attachment (1002) on the active layer (1001) of the at least one force sensor (1000). Computer-aided method for generating a control signal for a software application by means of one or more force sensors (1000) arranged on a body part (1040), preferably a head, according to one of the Claims 1 until 10 or set (1) according to one of the Claims 14 until 22 or Claim 25 The method comprises: detecting a pattern in an electrical signal generated by the electrical quantity of at least one of the force sensors (1000-1, 1000-2); and in response to the detected pattern, generating a control signal for a function of the software application. The procedure according to Claim 33 , where different detected patterns correspond to control signals of different functions of the software application. The procedure according to Claim 33 or 34 , wherein at least one of the force sensors (1000-1, 1000-2) is arranged on the body part (1040), preferably by means of the fitting (1), in such a way that a force caused by a movement of a muscle on the body part (1040) acts via the attachment (1002) on the active layer (1001) of the at least one force sensor (1000-1, 1000-2). The procedure according to one of the Claims 27 until 35 , further comprising: converting the electrical quantity of the at least one force sensor (1000-1, 1000-2) into the electrical signal by means of an electrical circuit, preferably wherein the electrical quantity is an electrical resistance and the electrical signal is an electrical voltage signal.

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