JP2014025791A - Calibration device and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a calibration device and a program that realize a simple configuration.SOLUTION: A CPU 40c acquires an output value of a gyro sensor and an output value of at least one of a geomagnetic sensor, an acceleration sensor and a distance sensor. The CPU 40c calculates both a first period when a housing kept in the sensors is in a first posture and a second period when the housing is in a second posture, on the basis of the output value of the gyro sensor, and calibrates at least one sensor on the basis of the output value of at least one sensor in the first and second periods.

Description

  The present invention relates to a calibration device that performs sensor calibration. The present invention also relates to a program for causing a computer to execute sensor calibration.

  Patent Document 1 discloses an apparatus that has a plurality of sensors such as a gyro sensor, an acceleration sensor, and a geomagnetic sensor and calibrates these sensors. In this apparatus, a composite sensor combining a gyro sensor, an acceleration sensor, a geomagnetic sensor, and the like is placed on a turntable that is rotated by a motor. Further, an inverted sensor is provided for detecting whether the rotation axis of the turntable is in the direction of gravity or the horizontal direction.

JP 2010-281598 A

  However, the apparatus disclosed in Patent Document 1 requires a mechanism (turn table, motor) for rotating the sensor and a mechanism (inverted sensor) for detecting the direction of the rotating shaft. Becomes complicated.

  SUMMARY An advantage of some aspects of the invention is that it provides a calibration apparatus and a program that can simplify the configuration.

  The present invention has been made to solve the above-described problem, and includes a gyro sensor, at least one of a geomagnetic sensor, an acceleration sensor, and a distance sensor, the gyro sensor, and the at least one sensor. A housing in which at least two postures are defined, and a processor for obtaining an output value of the gyro sensor and the at least one sensor, the processor based on the output value of the gyro sensor Calculating a first period when the attitude is the first attitude, and a second period when the attitude of the housing is the second attitude, in the first period and the second period The at least one sensor is calibrated based on the output value of the at least one sensor. It is a calibration apparatus according to claim.

  In the calibration device according to the aspect of the invention, the processor may determine a transition period when the attitude of the housing is changed from the first attitude to the second attitude based on the output value of the gyro sensor. And calculating and calibrating the gyro sensor based on the output value of the gyro sensor in the first period or the second period and the output value of the gyro sensor in the transition period. .

  In the calibration device of the present invention, the gyro sensor is a three-axis gyro sensor of an X axis, a Y axis, and a Z axis, and four attitudes of the housing are defined, and the processor Based on the output value of the sensor, the housing posture is the first period when the housing posture is the first posture, the second time period when the housing posture is the second posture, and the housing posture is the first time. A third period when the attitude is 3, and a fourth period when the attitude of the housing is the fourth attitude, the attitude of the housing is changed from the first attitude to the second attitude. A first transition period when the housing is in position, a second transition period when the posture of the housing is transitioned from the second position to the third position, and a position of the housing from the third position. Previous A third transition period when transitioning to the fourth posture is calculated, and in any one of the first period, the second period, the third period, and the fourth period The three-axis offset of the gyro sensor is calculated based on the output value of the gyro sensor, and the output value of the gyro sensor in the first transition period, the second transition period, and the third transition period is calculated. Based on this, a triaxial correction coefficient of the gyro sensor is calculated.

  In the calibration apparatus of the present invention, the acceleration sensor is a three-axis acceleration sensor of an X axis, a Y axis, and a Z axis, and three postures of the housing are defined, and the processor includes the gyro Based on the output value of the sensor, the first period when the attitude of the housing is the first attitude, the second period when the attitude of the housing is the second attitude, and the attitude of the housing Calculating a third period for the third posture, and calibrating the acceleration sensor based on output values of the acceleration sensor in the first period, the second period, and the third period It is characterized by performing.

  In the calibration device according to the aspect of the invention, the processor may calculate an offset of two axes among the three axes of the acceleration sensor based on an output value of the acceleration sensor in one of the first period and the second period. Calculating the offset of the remaining one of the three axes of the acceleration sensor based on the output value of the acceleration sensor in the other of the first period and the second period, and calculating the first period, A triaxial correction coefficient of the acceleration sensor is calculated based on the output value of the gyro sensor in the second period and the third period.

  In the calibration apparatus of the present invention, the geomagnetic sensor is a three-axis acceleration sensor of X-axis, Y-axis, and Z-axis, and three attitudes of the housing are defined, and the processor Based on the output value of the sensor, the first period when the attitude of the housing is the first attitude, the second period when the attitude of the housing is the second attitude, and the attitude of the housing A third period for the third posture is calculated, and calibration of the geomagnetic sensor is performed based on output values of the geomagnetic sensor in the first period, the second period, and the third period. It is characterized by performing.

  Further, in the calibration device according to the present invention, the processor is configured to offset the three axes of the geomagnetic sensor based on output values of the geomagnetic sensor in the first period, the second period, and the third period. And a correction coefficient is calculated.

  In the calibration apparatus of the present invention, the processor calibrates the distance sensor based on output values of the distance sensor in the first period and the second period.

  Further, in the calibration device of the present invention, the distance between the structure inside the housing and the distance sensor is different between when the housing is in the first posture and when in the second posture. It is characterized by being different.

  According to another aspect of the present invention, there is provided a gyro sensor, at least one of a geomagnetic sensor, an acceleration sensor, and a distance sensor, a housing on which the gyro sensor and the at least one sensor are mounted and at least two postures are defined. And a processor that obtains an output value of the at least one sensor, and the processor has a first attitude based on the output value of the gyro sensor. And a first step of calculating a second period when the attitude of the housing is a second attitude, and at least the first period and the second period. Calibration of the at least one sensor based on the output value of one sensor A second step of performing a program for execution.

  According to the present invention, a plurality of periods corresponding to a plurality of postures of the housing are calculated based on the output values of the gyro sensor, and the calibration of the other sensors is performed based on the output values of the other sensors in the plurality of periods. By doing so, the configuration can be simplified.

It is a block diagram which shows the structure of the endoscope system by one Embodiment of this invention. It is an external view of the front-end | tip adapter which the endoscope system by one Embodiment of this invention has. It is a permeation | transmission figure which shows the structure of the front-end | tip adapter which the endoscope system by one Embodiment of this invention has. It is a permeation | transmission figure which shows a mode that the front-end | tip adapter which the endoscope system by one Embodiment of this invention has is mounted | worn with the endoscope insertion part of an endoscope apparatus. It is a reference figure showing the composition of the distance sensor carried in the tip adapter which the endoscope system by one embodiment of the present invention has, and the principle of distance measurement. It is a block diagram which shows the connection of the two board | substrates mounted in the front-end | tip adapter which the endoscope system by one Embodiment of this invention has. It is a block diagram which shows the structure of the endoscope apparatus which the endoscope system by one Embodiment of this invention has. It is a block diagram which shows the structure of the indicator which the endoscope system by one Embodiment of this invention has. It is a block diagram which shows the structure of the calibration box which the endoscope system by one Embodiment of this invention has. It is a perspective view which shows the structure of the calibration box which the endoscope system by one Embodiment of this invention has. It is sectional drawing which shows the structure of the calibration box which the endoscope system by one Embodiment of this invention has. It is a reference figure showing the screen of sensing software in one embodiment of the present invention. It is a flowchart which shows the procedure of the operation | movement by the sensing measurement software in one Embodiment of this invention. It is a reference figure showing the screen of sensing software in one embodiment of the present invention. It is a flowchart which shows the procedure of the calibration operation | work in one Embodiment of this invention. It is a flowchart which shows the procedure of the calibration process in one Embodiment of this invention. It is a flowchart which shows the procedure of the calibration process of the gyro sensor in one Embodiment of this invention. It is a graph of the sensor data of the gyro sensor in one embodiment of the present invention. It is a graph of the sensor data of the gyro sensor in one embodiment of the present invention. It is a graph of the sensor data of the gyro sensor in one embodiment of the present invention. It is a flowchart which shows the procedure of the calibration process of the acceleration sensor in one Embodiment of this invention. It is a graph of the sensor data of the acceleration sensor in one embodiment of the present invention. It is a graph of the sensor data of the acceleration sensor in one embodiment of the present invention. It is a flowchart which shows the procedure of the calibration process of the geomagnetic sensor in one Embodiment of this invention. It is a graph of the sensor data of the geomagnetic sensor in one embodiment of the present invention. It is a graph of the sensor data of the geomagnetic sensor in one embodiment of the present invention. It is a flowchart which shows the procedure of the calibration process of the distance sensor in one Embodiment of this invention. It is a graph of the sensor data of the distance sensor in one embodiment of the present invention. It is a graph of the sample value of the distance sensor in one Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a configuration of an endoscope system according to an embodiment of the present invention. The endoscope system shown in FIG. 1 includes a tip adapter 1, an endoscope apparatus 2 having an endoscope insertion portion 20, and a display 3.

  The distal adapter 1 is used to acquire the direction of the endoscope insertion portion 20 and the distance from the distal end of the endoscope insertion portion 20 to the subject when observing or measuring the subject using the endoscope apparatus 2. Is a unit. Various sensors are mounted on the tip adapter 1. The tip adapter 1 can be attached to and detached from the endoscope insertion portion 20. Because the heat generated by the light source, the image sensor, etc. of the endoscope device 2 affects various sensors, or the metal constituting the hard part of the endoscope insertion portion 20 affects the geomagnetic sensor. Calibration of various sensors included in the tip adapter 1 is performed.

  The endoscope apparatus 2 is a device for observing and measuring a subject. An image is picked up by the imaging element in the endoscope insertion section 20 in a state where the endoscope insertion section 20 to which the distal adapter 1 is attached is inserted into the subject. The display 3 is a device for controlling the tip adapter 1. The display 3 is connected to the tip adapter 1 by a communication line 4.

  Next, the configuration of the tip adapter 1 will be described. FIG. 2 shows the appearance of the tip adapter 1. FIG. 2A is a front view of the tip adapter 1, and FIG. 2B is a side view of the tip adapter 1. The tip adapter 1 is covered with a plastic outer cover 10. As will be described later, since the geomagnetic sensor is mounted inside the tip adapter 1, no metal is used for the tip adapter 1.

  When the tip adapter 1 is viewed from the front as shown in FIG. 2A, a part of the periphery of the outer cover 10 is circular and the other part is linear. This is because the tip adapter 1 is fixed and stored in a predetermined direction in a calibration box described later. An attachment / detachment hole 11 is opened at the front center portion of the exterior cover 10, and the endoscope insertion portion 20 is inserted into the attachment / detachment hole 11 and fixed.

  A sensor line 12 is drawn on the front upper portion of the exterior cover 10. The sensor line 12 is for indicating a position where a sensor board, which will be described later, is arranged in the tip adapter 1. On the front left side of the exterior cover 10, a light emitting lens 301 and a light receiving lens 302 of a distance sensor 300, which will be described later, installed inside the exterior cover 10 are visible from the outside.

  As shown in FIG. 2B, when the tip adapter 1 is viewed from the side, the communication line 4 extends from the rear of the exterior cover 10. The communication line 4 is for performing communication and power supply between the tip adapter 1 and the display 3.

  FIG. 3 shows the configuration of the tip adapter 1 when the inside of the tip adapter 1 is viewed through the exterior cover 10 of the tip adapter 1. 3A is a front view of the tip adapter 1, FIG. 3B is a side view of the tip adapter 1, and FIG. 3C is a perspective view of the tip adapter 1. Two substrates (a main board 13 and a sensor board 14) are arranged inside the exterior cover 10. As shown in FIG. 3A, when the front end adapter 1 is viewed from the front, the main board 13 is disposed vertically in the central portion and the sensor board 14 is disposed horizontally in the upper portion inside the exterior cover 10. Yes.

  The main board 13 is a board that controls the entire tip adapter 1 and mainly includes a microcomputer 310 (MC) and a distance sensor 300 (DS). A detachable hole 11 is also opened in the center of the main board 13. The sensor board 14 is a board on which a sensor for detecting the direction of the tip adapter 1 is mounted, and a sensor group 320 including a gyro sensor, an acceleration sensor, and a geomagnetic sensor is arranged.

  The reason why the main board 13 and the sensor board 14 are spaced apart from each other is that various sensors on the sensor board 14 are easily affected by noise and heat. As shown in FIG. 3B, when the tip adapter 1 is viewed from the side, the communication line 4 extends from the rear of the main board 13. The main board 13 and the sensor board 14 are connected by a flat cable 15. As shown in FIG. 3C, when the tip adapter 1 is viewed obliquely, the gyro sensor 321 (GS), the acceleration sensor 322 (AS), and the geomagnetic sensor 323 (MS) are mounted on the sensor board 14.

  FIG. 4 shows a state in which the tip adapter 1 is attached to the endoscope insertion portion 20. In FIG. 4, the tip adapter 1 is shown in a state of being transmitted through the exterior cover 10. The endoscope adapter 1 is attached to the endoscope insertion portion 20 by inserting the endoscope insertion portion 20 into the attachment hole 11 of the tip adapter 1 from behind. The mounting position of the distal adapter 1 is determined so that the position of the distal end of the distal adapter 1 and the distal position of the endoscope inserting section 20 when the distal adapter 1 is mounted on the endoscope insertion section 20 are matched. ing.

  The endoscope insertion unit 20 includes a hard part 200 and a bending part 201 in order from the distal end side. The length of the tip adapter 1 is shorter than the length of the hard portion 200 so that the tip adapter 1 covers only the hard portion 200 when the tip adapter 1 is attached to the endoscope insertion portion 20. This is to prevent the distal end adapter 1 from covering the bending portion 201 so as to obstruct the bending of the endoscope distal end.

  Next, various sensors mounted on the tip adapter 1 will be described. The gyro sensor 321 is a sensor that detects an angular velocity when the sensor rotates with respect to a reference axis of the sensor itself. The acceleration sensor 322 is a sensor that detects acceleration applied to the sensor itself, and can also detect gravitational acceleration. The geomagnetic sensor 323 is a sensor that detects geomagnetism applied to the sensor itself, and can also detect magnetism emitted from a magnet or the like. The distance sensor 300 is a sensor that measures the distance from the sensor to the subject. The gyro sensor 321, the acceleration sensor 322, and the geomagnetic sensor 323 are three-axis sensors of the X axis, the Y axis, and the Z axis, respectively.

  Hereinafter, the configuration of the distance sensor 300 will be described. As shown in FIG. 3C, a light emitting lens 301 and a light receiving lens 302 are arranged side by side on the front surface of the distance sensor 300. FIG. 5 shows the configuration of the distance sensor 300 and the principle that the distance sensor 300 measures the distance. An LED 303 that emits infrared rays is mounted inside the light emitting lens 301, and an optical position sensor 304 is mounted inside the light receiving lens 302. An optical position sensor (Position Sensitive Detector, PSD) is a sensor which can obtain | require the gravity center position of the light quantity of the incident spot light.

  Hereinafter, the principle that the distance sensor 300 measures the distance from the sensor to the subject will be described. Infrared rays are irradiated from the LEDs 303 arranged inside the distance sensor 300 via the light emitting lens 301, and the infrared rays hit the subject 400 and are reflected. The reflected light enters the light receiving lens 302 and enters the optical position sensor 304 arranged inside the distance sensor 300. The optical position sensor 304 detects the position (incident position) where the reflected light is incident on the optical position sensor 304. From the relationship between the distance between the light emitting lens 301 and the light receiving lens 302 and the incident position on the optical position sensor 304, the distance to the subject 400 can be detected using the principle of triangulation.

  From the principle of triangulation, the distance to the subject and the incident position are inversely proportional to each other. In addition, the output (for example, analog voltage) of the distance sensor is proportional to the incident position. Therefore, the output value of the distance sensor 300 and the distance to the subject are in an inversely proportional relationship.

  FIG. 6 shows the connection between the main board 13 and the sensor board 14 of the tip adapter 1. The main board 13 and the sensor board 14 are electrically connected by a flat cable 15, and the main board 13 and the display 3 are electrically connected by a communication line 4.

  FIG. 6A shows the communication connection of the tip adapter 1. Communication between the microcomputer 310 on the main board 13 and each sensor on the sensor board 14 is performed via the flat cable 15, and the microcomputer 310 acquires sensor data that is an output value of each sensor from each sensor. The microcomputer 310 also acquires sensor data from the distance sensor 300. The communication method at this time may be serial communication (SPI, I2C) or AD conversion. The microcomputer 310 transmits the acquired sensor data to the display 3 via the communication line 4. The communication method at this time may be serial communication (RS232C).

  FIG. 6B shows power supply in the tip adapter 1. The display 3 has a built-in battery, and power is supplied from the battery to the main board 13 via the communication line 4. The power supplied to the main board 13 is supplied to the microcomputer 310 and the distance sensor 300. Further, the power is supplied to each sensor on the sensor board 14 via the flat cable 15.

  Next, the configuration of the endoscope apparatus 2 will be described. FIG. 7 shows the configuration of the endoscope apparatus 2. The endoscope apparatus 2 includes an endoscope insertion unit 20, an endoscope apparatus main body 21, a monitor 22, and a remote controller (remote controller) 23. An imaging optical system 30a and an imaging element 30b are built in the distal end of the endoscope insertion unit 20. The endoscope apparatus body 21 includes an image signal processing unit (CCU) 31, a light source 32, a bending control unit 33, and a control computer 34.

  In the endoscope insertion unit 20, the imaging optical system 30a collects light from the subject (subject) and forms a subject image on the imaging surface of the imaging element 30b. The image sensor 30b photoelectrically converts the subject image to generate an image signal. The imaging signal output from the imaging element 30 b is input to the image signal processing device 31.

  In the endoscope apparatus body 21, the image signal processing device 31 converts the image signal from the image sensor 30 b into a video signal such as an NTSC signal and supplies it to the control computer 34, and further, as an analog video output if necessary. Output to the outside.

  The light source 32 is connected to the distal end of the endoscope insertion portion 20 through an optical fiber or the like, and can irradiate light to the outside. The bending control unit 33 is connected to the distal end of the endoscope insertion unit 20 and can bend the distal end up and down and left and right. The light source 32 and the bending control unit 33 are controlled by the control computer 34.

  The control computer 34 includes a RAM 34a, a ROM 34b, a CPU 34c, an external interface RS232C I / F 34d, and a card I / F 34e. The RAM 34a is used for temporarily storing data such as image information necessary for software operation. A series of software (programs) for controlling the endoscope apparatus 2 is stored in the ROM 34b. The CPU 34c executes various control operations and the like using the data stored in the RAM 34a according to the software instruction code stored in the ROM 34b.

  The RS232C I / F 34d is an interface for connecting to the remote controller 23, and various operations of the endoscope apparatus 2 can be controlled by the user operating the remote controller 23. The card I / F 34e can freely attach and detach various memory cards 90 which are recording media. By mounting the memory card 90, data such as image information stored in the memory card 90 can be taken in or recorded in the memory card 90 under the control of the CPU 34c.

  Next, the configuration of the display device 3 will be described. FIG. 8 shows the configuration of the display 3. The display 3 includes a control computer 40, a monitor 41, and a power supply unit 42. The control computer 40 includes a RAM 40a, a ROM 40b, a CPU 40c (processor), and an RS232C I / F 40d that is an external interface.

  The RAM 40a is used to temporarily store sensor data and the like necessary for software operation. A series of software (programs) for controlling the display 3 is stored in the ROM 40b, and sensing software described later is also stored in the ROM 40b. The CPU 40c executes calculations for various controls using the data stored in the RAM 40a in accordance with the software instruction code stored in the ROM 40b.

  The RS232C I / F 40d is an interface for connecting the tip adapter 1 and the display device 3 via the communication line 4 and performing serial communication between the tip adapter 1 and the display device 3. The display device 3 can receive sensor data from the tip adapter 1 via the RS232C I / F 40d by an instruction from the CPU 40c.

  The monitor 41 displays an image based on a graphic image signal (display signal) such as a GUI (graphical user interface) of sensing software generated by the CPU 40c. The monitor 41 is configured as a touch panel, and outputs operation information when the user presses the screen of the monitor 41 to the CPU 40c. The power supply unit 42 (battery) supplies power to the control computer 40 and the monitor 41, and also supplies power to the tip adapter 1 via the communication line 4.

  Next, a configuration of a calibration box that is a housing in which the tip adapter 1 is housed when the sensors in the tip adapter 1 are calibrated will be described. FIG. 9 shows the appearance of the calibration box 5. The shape of the calibration box 5 is a rectangular parallelepiped. As will be described later, the calibration box 5 takes different postures depending on which face of the faces constituting the outer shape of the rectangular parallelepiped is placed downward. In a calibration operation to be described later, in order to smoothly rotate the calibration box 5, it is desirable that the corner of the calibration box 5 has a curved surface. The tip adapter 1, the display 3, and the calibration box 5 constitute a calibration device that calibrates each sensor in the tip adapter 1.

  A sensor line 50 is drawn on the upper part of the side surface of the calibration box 5. The sensor line 50 is for indicating a position where the sensor board 14 is disposed when the tip adapter 1 is installed inside the calibration box 5. The calibration box 5 is an openable type.

  FIG. 10 is a perspective view of the calibration box 5 when the calibration box 5 is opened. The calibration box 5 can be opened and closed with a hinge 51 as an axis. The rear (back side) inside the calibration box 5 has the same shape as the exterior cover 10 of the tip adapter 1, and the tip adapter 1 is attached to the endoscope insertion portion 20 as shown in FIG. The tip adapter 1 can be installed and fixed. At this time, the tip adapter 1 is installed so that the sensor line 12 of the tip adapter 1 is in the same direction (parallel) as the sensor line 50 of the calibration box 5.

  There is a rectangular space 52 in the front (front side) of the calibration box 5, and a rotating plate 53 is installed behind the space 52. The rotating plate 53 is configured to rotate about an axis according to the orientation of the calibration box 5, that is, the installation direction of the calibration box 5.

  FIG. 11 shows a cross section of the calibration box 5 with the tip adapter 1 installed. FIG. 11A shows the inside of the calibration box 5 when the calibration box 5 is installed so that the widest surface is horizontal and the axis of the rotating plate 53 is on the upper side. At this time, the rotating plate 53 rotates downward, which is the direction of gravity, and stops at a position away from the tip adapter 1 by a distance D1. In a calibration process described later, the distance sensor 300 in the tip adapter 1 measures a distance D1 from the tip adapter 1 to the rotating plate 53. FIG. 11B shows the inside of the calibration box 5 when the calibration box 5 is installed so that the narrowest surface of the calibration box 5 located on the tip side of the installed tip adapter 1 is horizontal. The configuration is shown. Also at this time, the rotating plate 53 rotates downward, which is the direction of gravity, and stops in a state where the main surface of the rotating plate 53 and the inner wall of the calibration box 5 are substantially parallel. During a calibration process described later, the distance sensor 300 in the tip adapter 1 measures a distance D2 (D1 <D2) from the tip adapter 1 to the inner wall of the calibration box 5.

  At this time, the rotating plate 53 is temporarily fixed to the rotational positions of FIGS. 11A and 11B by the click mechanism according to the direction of gravity, but is not fixed to other positions. Absent. Thus, according to the installation direction of the calibration box 5, the distance from the tip of the tip adapter 1 to the object located in front changes to the distances D1 and D2. By using this, two types of sensor data of the distance sensor 300 are acquired by rotating the calibration box 5 and changing the installation direction (posture) of the calibration box 5 at the time of calibration described later. Can do.

  Here, the direction axis and the rotation axis of the calibration box 5 are defined with reference to FIG. In FIG. 9, the tip adapter 1 to which the endoscope insertion portion 20 is attached is installed inside the calibration box 5, the sensor line 50 of the calibration box 5 faces upward, and the endoscope insertion portion 20 is A state is shown in which the calibration box 5 is placed facing the front side and the calibration box 5 being horizontal. At this time, the right direction of the calibration box 5 is the X-axis direction, the forward direction of the calibration box 5 is the Y-axis direction, and the upward direction of the calibration box 5 is the Z-axis direction. Further, the rotation direction of the right-hand screw is set as the X-axis rotation direction, the Y-axis rotation direction, and the Z-axis rotation direction with respect to each of the X-axis direction, the Y-axis direction, and the Z-axis direction.

  Next, a screen of sensing software that operates on the display 3 will be described. FIG. 12 is a main window of the sensing software. A main window 1200 shown in FIG. 12 is displayed on the monitor 41 when the user activates the sensing software. The CPU 40c performs processing based on operations of various GUIs in the main window 1200 according to the sensing software. The display of the main window 1200 is performed according to control by the CPU 40c. The CPU 40 c generates a graphic image signal (display signal) for displaying the main window 1200 and outputs it to the monitor 41. The user operates the main window 1200 using the GUI function and inputs various instructions.

  When updating the GUI display state on the main window 1200, the CPU 40c generates a graphic image signal corresponding to the updated main window 1200, and performs the same processing as described above. Processing related to display of windows other than the main window 1200 is the same as described above. Hereinafter, the process in which the CPU 40c generates a graphic image signal to display the main window 1200 or the like (including updating) will be referred to as a process to display the main window 1200 or the like.

  Hereinafter, various GUIs arranged on the main window 1200 will be described. In the upper left part of the main window 1200, a [Measurement Result] box 1210 is arranged. [Measurement result] box 1210 displays measurement result data. The measurement result data is data on the bending direction (yaw, roll, pitch) of the sensor board 14 in the tip adapter 1 and data on the distance from the tip adapter 1 to the subject.

  At the center of the main window 1200, a [Distance Data] indicator 1220 is arranged. [Distance data] indicator 1220 is a GUI for displaying the size by a bar, and the length of the bar changes depending on the distance from the tip adapter 1 to the subject.

  On the lower left side of the main window 1200, a [yaw direction] indicator 1230 is arranged. [Yaw direction] indicator 1230 is a GUI for displaying a direction by a compass, and the direction of the compass changes depending on the yaw direction of the endoscope insertion unit 20 (rotation direction about the top and bottom, azimuth direction).

  In the lower center of the main window 1200, a [roll direction] indicator 1240 is arranged. [Roll direction] indicator 1240 is a GUI that displays a direction using a compass, and the direction of the compass changes depending on the roll direction of the endoscope insertion unit 20 (the rotation direction about the front and rear axes).

  A [Pitch direction] indicator 1250 is arranged on the lower right side of the main window 1200. [Pitch direction] indicator 1250 is a GUI for displaying a direction by a compass, and the direction of the compass changes depending on the pitch direction of the endoscope insertion unit 20 (the rotation direction about the left and right axes).

  In the upper right part of the main window 1200, a [Measurement start] button 1260, a [Measurement stop] button 1270, and a [Calibration] button 1280 are arranged. [Measurement start] button 1260 is a button for starting acquisition of measurement result data which is a measurement result of each sensor. When the [Measurement Start] button 1260 is pressed, measurement result data is continuously acquired from the sensor board 14 in the tip adapter 1, and the result is reflected in the [Measurement Result] box 1210 and various indicators.

  [Measurement stop] button 1270 is a button for stopping acquisition of measurement result data. When the [Measurement Stop] button 1270 is pressed, the measurement state, that is, the state where measurement result data is continuously acquired from the tip board stops. [Calibration] button 1280 is a button for calibrating various sensors built in tip adapter 1. When the [Calibration] button 1280 is pressed, a calibration window is displayed, and the user can perform calibration via the calibration window.

  Next, the operation flow of the sensing software will be described with reference to FIG. In step S100, the user inputs an instruction to start the sensing software. In step S105, the CPU 40c detects an instruction input by the user and performs a process of displaying the main window 1200. In step S110, the user presses the [Calibration] button 1280. In step S115, the CPU 40c detects that the [calibration] button 1280 has been pressed by the user, and performs processing according to the calibration work performed by the user. Details of the calibration operation will be described later.

  In step S120, the user presses the [Measurement Start] button 1260. In step S125, the CPU 40c detects that the [Measurement start] button 1260 has been pressed by the user, and requests the tip adapter 1 to transmit sensor data. In step S130, the CPU 40c receives the sensor data transmitted from the tip adapter 1.

  In step S135, the CPU 40c calculates the bending direction of the tip adapter 1 and the distance from the tip adapter 1 to the subject based on the received sensor data, and generates bending direction data and distance data as calculation results. In step S140, the CPU 40c performs a process for displaying the calculated bending direction and distance in the [Measurement Result] box 1210. Further, the CPU 40c changes the bar of the [distance data] indicator 1220 according to the size of the distance data. Steps S125 to S140 are repeated until the user presses the [Measurement Stop] button 1270.

  In step S145, the user inputs an instruction to end the sensing software. In step S150, the CPU 40c detects an instruction input by the user, hides the main window 1200, and ends all software operations.

  In the above processing flow, the processing proceeds in the order of calibration, measurement, and software termination.However, the processing order is not necessarily the same, and the measurement can be performed before calibration. You can also exit the software before doing it.

  FIG. 14 shows a calibration window displayed on the monitor 41 when the user presses the [Calibration] button 1280 in step S110. Display of the calibration window 1400 shown in FIG. 14 is performed according to control by the CPU 40c. The CPU 40 c generates a graphic image signal (display signal) for displaying the calibration window 1400 and outputs it to the monitor 41. The user operates the calibration window 1400 using the GUI function and inputs various instructions.

  Hereinafter, various GUIs arranged on the calibration window 1400 will be described. An instruction message 1410 is displayed in the upper left part of the calibration window 1400. The instruction message 1410 is a message for instructing an operation required when the user performs calibration of the tip adapter 1.

  An installation direction illustration 1420 of the calibration box 5 is displayed at the bottom of the calibration window 1400. The installation direction illustration 1420 is an illustration showing the work required when the user calibrates the tip adapter 1. This is an illustration of the content of the instruction message 1410 as it is.

  In the upper right part of the calibration window 1400, a [Start] button 1430 and a [Stop] button 1440 are arranged. [Start] button 1430 and [Stop] button 1440 are buttons for starting and stopping calibration, respectively.

  A processing message 1450 is displayed at the center of the calibration window 1400. The processing message 1450 is a message for notifying the user that the calibration is being calculated.

  Next, the flow of calibration work will be described with reference to FIG. When the user presses the [Calibration] button 1280 in step S110, the CPU 40c performs a process for displaying the calibration window 1400 in step S200. The calibration window 1400 displayed at this time is a modal window, and the user can operate only the calibration window 1400. Further, the calibration window 1400 is always superimposed and displayed on the upper side (near side) of the main window 1200.

  In step S205, the user presses the [Start] button 1430. In step S210, the CPU 40c detects that the [Start] button 1430 has been pressed by the user, and starts recording various sensor data. Thereafter, the CPU 40c receives sensor data from the tip adapter 1 at a predetermined sampling period and continues to record the received sensor data in the RAM 40a until it is detected that the user presses the [Stop] button 1440.

  In step S215, the CPU 40c performs processing for displaying an instruction message 1410 for instructing the user to perform work necessary for calibration as shown in FIG. In step S220, the user installs the calibration box 5 in the installation direction 1. As shown in the installation direction illustration 1420 in FIG. 14, the installation direction 1 is such that the sensor line 50 faces upward, the endoscope insertion portion 20 faces frontward, and the widest surface of the calibration box 5 is horizontal. It is the installation direction (posture) that becomes.

  In step S225, the user rotates the calibration box 5 in the forward direction and installs it in the installation direction 2. The installation direction 2 is an installation direction (posture) obtained by rotating the calibration box 5 forward 90 degrees (deg) from the installation direction 1 as indicated by the installation direction illustration 1420 of FIG.

  In step S230, the user rotates the calibration box 5 in the right direction and installs it in the installation direction 3. The installation direction 3 is an installation direction (posture) obtained by rotating the calibration box 5 90 degrees (deg) to the right from the installation direction 2 as indicated by the installation direction illustration 1420 of FIG.

  In step S235, the user rotates the calibration box 5 in the forward direction and installs it in the installation direction 4. The installation direction 4 is an installation direction obtained by rotating the calibration box 5 forward 90 degrees (deg) from the installation direction 3 as indicated by the installation direction illustration 1420 of FIG.

  In steps S220 to S235, the user performs the rotation / installation work of the calibration box 5 while taking a predetermined time. For example, the calibration box 5 is rotated for 1 second, and after the calibration box 5 is installed in a predetermined installation direction, the rotation is performed again after waiting for 1 second. The reason for this is that the CPU 40c needs to perform calibration processing, which will be described later, reliably using sensor data during rotation and installation of the calibration box 5.

  In step S240, the user presses the [Stop] button 1440. In step S245, the CPU 40c detects that the [stop] button 1440 has been pressed by the user, and stops recording various sensor data. In step S250, the CPU 40c performs processing for displaying a processing message 1450 for notifying the user that the calibration is being calculated as shown in FIG.

  In step S255, the CPU 40c performs a calibration process based on various sensor data recorded in the RAM 40a. Details of the calibration process will be described later. In step S260, the CPU 40c performs a process for displaying a message for notifying the user that the calibration is completed, and ends the calibration work.

  Next, the flow of calibration processing in step S255 will be described using FIG. In step S300, the CPU 40c performs a calibration process for the gyro sensor 321 based on the sensor data of the gyro sensor 321. Details of the calibration process of the gyro sensor 321 will be described later. In step S305, the CPU 40c performs calibration processing of the acceleration sensor 322 based on the sensor data of the acceleration sensor 322. Details of the calibration process of the acceleration sensor 322 will be described later.

  In step S310, the CPU 40c performs a calibration process for the geomagnetic sensor 323 based on the sensor data of the geomagnetic sensor 323. Details of the calibration process of the geomagnetic sensor 323 will be described later. In step S315, the CPU 40c performs the calibration process of the distance sensor 300 based on the sensor data of the distance sensor 300, and ends the calibration process. Details of the calibration process of the distance sensor 300 will be described later.

  Next, the flow of the calibration process of the gyro sensor 321 in step S300 will be described with reference to FIG. In step S400, the CPU 40c reads the sensor data of the gyro sensor 321 recorded in the RAM 30a. In step S405, the CPU 40c calculates the rotation / rest timing of the calibration box 5 based on the read sensor data. The rotation / rest timing of the calibration box 5 is a period during which the user rotates and installs (stills) the calibration box 5 in steps S220 to S235.

  Hereinafter, how the CPU 40c calculates the rotation / stop timing of the calibration box 5 based on the sensor data of the gyro sensor 321 will be described with reference to FIGS. FIG. 18A is a graph of sensor data of the gyro sensor 321 recorded in the RAM 40a. The horizontal axis represents time (sensor data acquisition time), and the vertical axis represents the output value. Since the gyro sensor 321 is a sensor that detects angular velocity, if the gyro sensor 321 is stationary, the sensor data hardly changes and is constant, and if the gyro sensor 321 rotates, the sensor data changes greatly. It should be.

  Hereinafter, the sensor data of the gyro sensor 321 will be described in chronological order (horizontal axis direction) with reference to FIG. First, focus on the first period. During this period, the sensor data changes for all three axes. This is a preparation period from when the user starts calibration until the calibration box 5 is installed in the installation direction 1.

  In the next period, the sensor data does not change for all three axes and is almost constant. This period is a period during which the user installs the calibration box 5 in the installation direction 1 (a stationary period in which the calibration box 5 is stationary in a predetermined posture). However, even though the calibration box 5 is stationary, the sensor data is not necessarily 0, and indicates an output of a predetermined size. This is due to drift (fluctuation) when the gyro sensor 321 is stationary.

  In the next period, sensor data for only the X-axis changes significantly. This period is a period during which the user rotates the calibration box 5 from the installation direction 1 to the installation direction 2 (a transition period during which the posture of the calibration box 5 is shifted to the next posture). Since the calibration box 5 rotates in the forward direction, the sensor data of only the X axis changes.

  In the next period, the sensor data does not change for all three axes and is almost constant. This period is a period during which the user installs the calibration box 5 in the installation direction 2 (stationary period).

  In the next period, the sensor data changes greatly only for the Z axis. This period is a period during which the user rotates the calibration box 5 from the installation direction 2 to the installation direction 3 (transition period). Since the calibration box 5 rotates in the right direction, the sensor data of only the Z axis changes.

  In the next period, the sensor data does not change for all three axes and is almost constant. This period is a period during which the user installs the calibration box 5 in the installation direction 3 (stationary period).

  In the next period, the sensor data changes greatly only for the Y axis. This period is a period during which the user rotates the calibration box 5 from the installation direction 3 to the installation direction 4 (transition period). Since the calibration box 5 rotates in the front direction, the sensor data of only the Y axis changes.

  In the last period, sensor data does not change and is almost constant for all three axes. This period is a period (stationary period) from when the user installs the calibration box 5 in the installation direction 4 to stop calibration.

  Thus, by analyzing how and when the sensor data changes, it is possible to determine how the calibration box 5 is rotated and stationary.

As shown in FIG. 19A, the CPU 40c calculates the rotation / rest timing of the calibration box 5 as periods Ph1 to Ph8 based on the sensor data. The following is a description regarding each period.
Ph1: The user is preparing to install the calibration box 5.
Ph2: The calibration box 5 is installed in the installation direction 1 and is stationary.
Ph3: The calibration box 5 is rotating forward.
Ph4: The calibration box 5 is installed in the installation direction 2 and is stationary.
Ph5: The calibration box 5 is rotating in the right direction.
Ph6: The calibration box 5 is installed in the installation direction 3 and is stationary.
Ph7: The calibration box 5 is rotating forward.
Ph8: The calibration box 5 is installed in the installation direction 4 and is stationary.

  Information of the periods Ph1 to Ph8 is recorded in the RAM 40a. As will be described later, the CPU 40c uses the periods Ph1 to Ph8 obtained here also in the calibration processing of other sensors. The sensor data of each sensor is associated with one of the periods Ph1 to Ph8 according to the acquisition time.

  Subsequently, in step S410, the CPU 40c calculates an offset value of the sensor data of each of the three axes of the gyro sensor 321. The offset value is a value that is added to the sensor data of the gyro sensor 321 due to drift when the gyro sensor 321 is stationary. As shown in FIG. 19B, the CPU 40c calculates the respective offset values of the three axes by averaging the three axis sensor data of the gyro sensor 321 in the period Ph2. The offset value may be calculated by averaging the sensor data of the gyro sensor 321 in the period Ph4 or the period Ph6.

  In step S415, the CPU 40c removes the offset of the sensor data of each of the three axes of the gyro sensor 321. The removal of the offset is performed by dividing the offset value from the sensor data of the gyro sensor 321 over the entire period. FIG. 20A shows sensor data of the gyro sensor 321 after the offset is removed. It can be seen that the sensor data during the period when the gyro sensor 321 is stationary is substantially 0 and constant.

  In step S420, the CPU 40c calculates a correction parameter for the gyro sensor 321. The correction parameter of the gyro sensor 321 is a correction coefficient used when the sensor data of the gyro sensor 321 is converted into an angle that the gyro sensor 321 has actually rotated (hereinafter, gyro sensor rotation angular velocity).

  Here, a method for calculating the X-axis correction parameter of the gyro sensor 321 will be described. When the output value of the gyro sensor is multiplied by the gyro sensor conversion coefficient, which is a conversion coefficient for converting the output value of the gyro sensor into the gyro sensor rotation angular speed, the gyro sensor rotation angular speed (deg / sec) is calculated. The gyro sensor conversion coefficient is a value unique to the gyro sensor and is defined as a specification. The CPU 40c calculates the X-axis gyro sensor angular velocity (deg) by time-integrating the X-axis sensor data in the period Ph3 for each sampling period and multiplying the integrated value by the gyro sensor conversion coefficient.

  Here, the X-axis gyro sensor rotation angle in the period Ph3 should be 90 deg from the outer shape of the calibration box 5. However, the actually calculated rotation angle often has a value slightly different from 90 deg. This is due to drift during rotation of the gyro sensor 321 and the like. Therefore, the CPU 40c calculates a ratio between the X-axis gyro sensor rotation angle and 90 deg, and calculates this ratio as an X-axis correction parameter. Similarly, the CPU 40c calculates the Y-axis correction parameter using the Y-axis sensor data in the period Ph7, and calculates the Z-axis correction parameter using the Z-axis sensor data in the period Ph5 (FIG. 20B). )).

  In step S425, the CPU 40c records the offset values and correction parameters for the three axes in the RAM 40a as the calibration result of the gyro sensor 321, and ends the calibration process of the gyro sensor 321. After the calibration, when using the sensor data of the gyro sensor 321, the CPU 40c performs calibration using the calibration result of the gyro sensor 321 calculated as described above. That is, the CPU 40c first removes the offset from the sensor data of the gyro sensor 321 over the entire period. When the gyro sensor rotation angle is calculated, the sensor data of the gyro sensor 321 is multiplied by the gyro sensor conversion coefficient and the correction parameter.

  Next, the flow of the calibration process of the acceleration sensor 322 in step S305 will be described with reference to FIG. In step S500, the CPU 40c reads the sensor data of the acceleration sensor 322 recorded in the RAM 40c. FIG. 22A is a graph of sensor data of the acceleration sensor 322 recorded in the RAM 40a. The horizontal axis represents time (sensor data acquisition time), and the vertical axis represents the output value.

  In step S505, the CPU 40c calculates an offset value of each sensor data of the three axes of the acceleration sensor 322 based on the read sensor data. The offset value is a value that is added to the sensor data of the acceleration sensor 322 due to drift when the acceleration sensor 322 is stationary. As shown in FIG. 22B, the CPU 40c calculates the offset value by averaging the sensor data of the acceleration sensor 322 in the periods Ph2 and Ph4 over time. More specifically, the CPU 40c calculates X-axis and Y-axis offset values based on the X-axis and Y-axis sensor data of the acceleration sensor 322 in the period Ph2, and the Z-axis sensor of the acceleration sensor 322 in the period Ph4. Based on the data, the Z-axis offset value is calculated.

  In step S510, the CPU 40c removes the offset of the sensor data of each of the three axes of the acceleration sensor 322. The removal of the offset is performed by dividing the offset value from the sensor data of the acceleration sensor 322 over the entire period. FIG. 23A shows sensor data of the acceleration sensor 322 after the offset is removed. It can be seen that for each axis of the acceleration sensor 322, the sensor data during a period in which the acceleration sensor 322 does not face the gravitational direction is almost zero and constant.

  In step S515, the CPU 40c calculates a correction parameter for the acceleration sensor 322. The correction parameter of the acceleration sensor 322 is a correction coefficient used when the sensor data of the acceleration sensor 322 is converted into an acceleration actually received by the acceleration sensor 322 (hereinafter referred to as acceleration sensor acceleration).

Here, a method of calculating the X-axis correction parameter of the acceleration sensor 322 will be described. When the output value of the acceleration sensor 322 is multiplied by the acceleration sensor conversion coefficient, which is a conversion coefficient for converting the output value of the acceleration sensor 322 into acceleration sensor acceleration, the acceleration sensor acceleration (m / sec ² ) is calculated. The acceleration sensor conversion coefficient is a value unique to the acceleration sensor and is defined as a specification. The CPU 40c calculates the time average of the X-axis sensor data in the period Ph6, and calculates the X-axis acceleration sensor acceleration by multiplying the calculated time average by the acceleration sensor conversion coefficient.

Here, since the acceleration sensor acceleration on the X axis in the period Ph6 coincides with the gravitational acceleration, it should be 1G, that is, 9.8 (m / sec ² ). However, the actually calculated acceleration often has a value slightly different from 1G. This is due to drift during rotation of the acceleration sensor 322 or the like. Therefore, the CPU 40c calculates a ratio between the acceleration sensor acceleration on the X axis and 1G, and calculates this ratio as an X axis correction parameter. Similarly, the CPU 40c calculates Y-axis correction parameters using the Y-axis sensor data in the period Ph4, and calculates Z-axis correction parameters using the Z-axis sensor data in the period Ph2 (FIG. 23B). )).

  In step S520, the CPU 40c records the offset values and correction parameters for the three axes in the RAM 40a as the calibration result of the acceleration sensor 322, and the calibration process of the acceleration sensor 322 is terminated. After calibration, when using the sensor data of the acceleration sensor 322, the CPU 40c performs calibration using the calibration result of the acceleration sensor 322 calculated as described above. That is, the CPU 40c first removes the offset from the sensor data of the acceleration sensor 322 over the entire period. When calculating the acceleration of the acceleration sensor, the sensor data of the acceleration sensor 322 is multiplied by the acceleration sensor conversion coefficient and the correction parameter.

  Next, the flow of the calibration process of the geomagnetic sensor 323 in step S310 will be described with reference to FIG. In step S600, the CPU 40c reads the sensor data of the geomagnetic sensor 323 recorded in the RAM 40a. FIG. 25A is a graph of sensor data of the geomagnetic sensor 323 recorded in the RAM 40a. The horizontal axis represents time (sensor data acquisition time), and the vertical axis represents the output value.

  In step S605, the CPU 40c calculates an offset value of the sensor data of each of the three axes of the geomagnetic sensor 323 based on the read sensor data. The offset value is a value that is added to the sensor data of the geomagnetic sensor 323 due to a drift when the geomagnetic sensor 323 is stationary. As shown in FIG. 25B, the CPU 40c calculates an offset value by averaging the sensor data of the geomagnetic sensor 323 in the periods Ph2, Ph4, and Ph6 over time. More specifically, the CPU 40c calculates the Z-axis offset value based on the Z-axis sensor data of the geomagnetic sensor 323 in the period Ph2, and based on the Y-axis sensor data of the geomagnetic sensor 323 in the period Ph4. And the X-axis offset value is calculated based on the X-axis sensor data of the geomagnetic sensor 323 in the period Ph6.

  In step S600, the CPU 40c removes the offset of the sensor data of each of the three axes of the geomagnetic sensor 323. The removal of the offset is performed by dividing the offset value from the sensor data of the geomagnetic sensor 323 over the entire period. FIG. 26A shows sensor data of the geomagnetic sensor 323 after the offset is removed. For each axis of the geomagnetic sensor 323, it can be seen that the sensor data during the period in which the direction is the gravitational direction is almost zero and constant.

  In step S615, the CPU 40c calculates a correction parameter for the geomagnetic sensor 323. The correction parameter of the geomagnetic sensor 323 is a correction coefficient used when the sensor data of the geomagnetic sensor 323 is converted into the geomagnetism actually received by the geomagnetic sensor 323 (hereinafter referred to as geomagnetic sensor geomagnetism).

  Here, a method for calculating the correction parameter of the geomagnetic sensor 323 will be described. First, as shown in FIG. 26B, the time average of the X-axis sensor data of the geomagnetic sensor 323 in the period Ph2 is Mx1, and the time average of the Y-axis sensor data is My1. Similarly, the time average of the X-axis sensor data of the geomagnetic sensor 323 in the period Ph4 is Mx1, and the time average of the Z-axis sensor data is Mz1. At this time, the time average of the X-axis sensor data of the geomagnetic sensor 323 is the same value Mx1 in both the periods Ph2 and Ph4. This is because the X-axis direction of the calibration box 5 does not change during the periods Ph2 and Ph4.

  Furthermore, the time average of the Y-axis sensor data of the geomagnetic sensor 323 in the period Ph6 is My2, and the time average of the Z-axis sensor data is Mz1. At this time, the time average of the Z-axis sensor data of the geomagnetic sensor 323 is the same value Mz1 in both the periods Ph4 and Ph6. This is because the Z-axis direction of the calibration box 5 does not change during the periods Ph4 and Ph6.

  When the output value of the geomagnetic sensor 323 is multiplied by the output value of the geomagnetic sensor 323, the geomagnetic sensor conversion coefficient that is a conversion coefficient for converting the output value of the geomagnetic sensor 323 into the geomagnetic sensor geomagnetism, the geomagnetic sensor geomagnetism (T, Tesla) is calculated. The geomagnetic sensor conversion coefficient is a value unique to the geomagnetic sensor and is defined as a specification. The CPU 40c calculates the geomagnetic sensor geomagnetism of each of the three axes by multiplying the triaxial sensor data in the periods Ph2, Ph4, and Ph6 by the geomagnetic sensor conversion coefficient.

  Here, in the period Ph2, when Mx1 and My1 are multiplied by the geomagnetic sensor conversion coefficient and the square sum of the multiplication results is taken, it should be the square of the actual geomagnetism E (T). However, the actually calculated value is often slightly different from the geomagnetism E. This is due to drift during rotation of the geomagnetic sensor 323. Therefore, the CPU 40c calculates correction coefficients for multiplying the X-axis sensor data and the Y-axis sensor data of the geomagnetic sensor 323, and uses these as the X-axis correction parameter and the Y-axis correction parameter. Also in the periods Ph4 and Ph6, based on the same concept, the CPU 40c calculates a correction coefficient by which the Z-axis sensor data of the geomagnetic sensor 323 is multiplied, and uses this as a Z-axis correction parameter.

  Here, assuming that the X-axis, Y-axis, and Z-axis geomagnetic sensor conversion coefficients are Cx, Cy, Cz, X-axis, Y-axis, and Z-axis correction parameters are γx, γy, and γz, respectively, Formulas (Formula (1), Formula (2), Formula (3)) hold.

  Since the geomagnetic sensor conversion coefficients Cx, Cy, Cz and the geomagnetism E are known, the correction parameters γx, γy, γz of the geomagnetic sensor 323 can be obtained from the above relational expression.

  Subsequently, in step S620, the CPU 40c records the offset values and correction parameters for the three axes in the RAM 40a as the calibration result of the geomagnetic sensor 323, and ends the calibration process of the geomagnetic sensor 323. After the calibration, when using the sensor data of the geomagnetic sensor 323, the CPU 40c performs calibration using the calibration result of the geomagnetic sensor 323 calculated as described above. That is, the CPU 40c first removes the offset from the sensor data of the geomagnetic sensor 323 over the entire period. When calculating the geomagnetic sensor geomagnetism, the sensor data of the geomagnetic sensor 323 is multiplied by the geomagnetic sensor conversion coefficient and the correction parameter.

  Next, the flow of the calibration process of the distance sensor 300 in step S315 will be described using FIG. In step S700, the CPU 40c reads the sensor data of the distance sensor 300 recorded in the RAM 40a. FIG. 28A is a graph of sensor data of the distance sensor 300 recorded in the RAM 40a. The horizontal axis represents time (sensor data acquisition time), and the vertical axis represents the output value. As described above, in the distance sensor, the output value and the measured distance are in an inversely proportional relationship. Therefore, the smaller the measured distance, the larger the output value, and the larger the measured distance, the smaller the output value.

  In step S705, the CPU 40c calculates a sample value of sensor data of the distance sensor 300. At this time, the CPU 40c calculates the sample value by time-averaging the sensor data of the distance sensor 300 in each of the periods Ph2 and Ph4 as shown in FIG. In the period Ph2, as shown in FIG. 11A, the rotary plate 53 is stationary at a position away from the tip adapter 1 by a distance D1. In the period Ph4, as shown in FIG. 11B, the rotating plate 53 is stationary with the main surface of the rotating plate 53 and the inner wall of the calibration box 5 being substantially parallel. The sample value 1 is calculated from the sensor data of the distance sensor 300 in the period Ph2, and the sample value 2 is calculated from the sensor data of the distance sensor 300 in the period Ph4.

  FIG. 29A is a graph in which two calculated sample values are plotted. The horizontal axis is the distance, and the vertical axis is the output value.

  In step S710, the CPU 40c calculates a relational expression between the output value and the distance based on the calculated two sample values. FIG. 29B is a graph plotting the relationship between the output value and the distance. As described above, since they are in an inversely proportional relationship, a relational expression between them can be calculated using only two sample values.

  In step S715, the CPU 40c records the relational expression between the output value and the distance as a calibration result of the distance sensor 300 in the RAM 40a, and ends the calibration process of the distance sensor 300. After the calibration, when using the sensor data of the distance sensor 300, the CPU 40c performs calibration using the calibration result of the distance sensor 300 calculated as described above. That is, the CPU 40c converts the sensor data of the distance sensor 300 into distance data using the above relational expression.

  In this embodiment, the gyro sensor 321, the acceleration sensor 322, the geomagnetic sensor 323, and the distance sensor 300 are mounted on the tip adapter 1, but the sensors mounted on the tip adapter 1 are the gyro sensor 321 and the acceleration sensor 322. , One or more of the geomagnetic sensor 323 and the distance sensor 300 may be used. In the present embodiment, the sensing software is mounted on the display device 3, but the sensing software may be mounted on the tip adapter 1 or the endoscope device 2.

  As described above, according to the present embodiment, the CPU 40c of the display 3 calculates a plurality of periods corresponding to a plurality of postures of the calibration box 5 that is a housing based on the sensor data of the gyro sensor 321. Each sensor is calibrated based on sensor data of the acceleration sensor 322, the geomagnetic sensor 323, and the distance sensor 300 in a plurality of periods. In this embodiment, since the user rotates the calibration box 5 according to a predetermined procedure, a mechanism for rotating each sensor and a mechanism for detecting the direction of the rotation axis become unnecessary. Can be simplified.

  As described above, the embodiments of the present invention have been described in detail with reference to the drawings. However, the specific configuration is not limited to the above-described embodiments, and includes design changes and the like without departing from the gist of the present invention. .

  DESCRIPTION OF SYMBOLS 1 ... Tip adapter, 2 ... Endoscope apparatus, 3 ... Display, 4 ... Communication line, 5 ... Calibration box, 10 ... Exterior cover, 13 ... Main Board, 14 ... Sensor board, 15 ... Flat cable, 20 ... Endoscope insertion part, 21 ... Endoscope body, 22, 41 ... Monitor, 23 ... Remote control, 30a ... Imaging optical system, 30b ... Imaging element, 31 ... Image signal processing device, 32 ... Light source, 33 ... Bending control unit, 34, 40 ... Control computer, 34a, 40a ... RAM, 34b, 40b ... ROM, 34c, 40c ... CPU, 34d, 40d ... RS232C I / F, 34e ... Card I / F, 42 ... Power supply unit, 300 ... Distance sensor, 301 ... Light emitting lens, 302... Light receiving lens, 303... LED, 304... Optical position sensor, 310... Microcomputer, 321... Gyro sensor, 322.

Claims (10)

Gyro sensor,
At least one of a geomagnetic sensor, an acceleration sensor, and a distance sensor;
A housing in which the gyro sensor and the at least one sensor are mounted and at least two postures are defined;
A processor for obtaining an output value of the gyro sensor and the at least one sensor,
The processor, based on the output value of the gyro sensor, a first period when the attitude of the housing is the first attitude, and a second period when the attitude of the housing is the second attitude And calibrating the at least one sensor based on an output value of the at least one sensor in the first period and the second period.   The processor calculates a transition period when the attitude of the housing is shifted from the first attitude to the second attitude based on the output value of the gyro sensor, and the first period or the The calibration apparatus according to claim 1, wherein the gyro sensor is calibrated based on an output value of the gyro sensor in a second period and an output value of the gyro sensor in the transition period. The gyro sensor is a three-axis gyro sensor of X axis, Y axis, and Z axis,
Four postures of the housing are defined,
The processor is
Based on the output value of the gyro sensor, the first period when the attitude of the housing is the first attitude, the second period when the attitude of the housing is the second attitude, the attitude of the housing In the third period when is the third attitude, and in the fourth period when the attitude of the housing is the fourth attitude, the attitude of the housing is changed from the first attitude to the second attitude. A first transition period when the housing is in position, a second transition period when the posture of the housing is transitioning from the second position to the third position, and a position of the housing is the third transition period. Calculating a third transition period when transitioning from the posture to the fourth posture;
The three-axis offset of the gyro sensor is calculated based on the output value of the gyro sensor in any one of the first period, the second period, the third period, and the fourth period. ,
The triaxial correction coefficient of the gyro sensor is calculated based on output values of the gyro sensor in the first transition period, the second transition period, and the third transition period. 2. The calibration apparatus according to 2. The acceleration sensor is an X-axis, Y-axis, Z-axis three-axis acceleration sensor,
Three orientations of the housing are defined,
The processor, based on the output value of the gyro sensor, a first period when the attitude of the housing is a first attitude, a second period when the attitude of the housing is a second attitude, And a third period when the attitude of the housing is the third attitude, and based on the output value of the acceleration sensor in the first period, the second period, and the third period The calibration apparatus according to claim 1, wherein the acceleration sensor is calibrated. The processor is
Based on the output value of the acceleration sensor in one of the first period and the second period, an offset of two axes among the three axes of the acceleration sensor is calculated,
Calculating an offset of the remaining one of the three axes of the acceleration sensor based on the output value of the acceleration sensor in the other of the first period and the second period;
5. The triaxial correction coefficient of the acceleration sensor is calculated based on output values of the gyro sensor in the first period, the second period, and the third period. 6. Calibration equipment. The geomagnetic sensor is a three-axis acceleration sensor of X axis, Y axis, and Z axis,
Three orientations of the housing are defined,
The processor is
Based on the output value of the gyro sensor, a first period when the attitude of the housing is the first attitude, a second period when the attitude of the housing is the second attitude, and the housing Calculating a third period when the posture is the third posture;
The calibration apparatus according to claim 1, wherein the geomagnetic sensor is calibrated based on output values of the geomagnetic sensor in the first period, the second period, and the third period. . The processor calculates a three-axis offset and a correction coefficient of the geomagnetic sensor based on output values of the geomagnetic sensor in the first period, the second period, and the third period. The calibration device according to claim 6.   The calibration device according to claim 1, wherein the processor calibrates the distance sensor based on output values of the distance sensor in the first period and the second period.   The distance between the structure inside the housing and the distance sensor is different depending on whether the posture of the housing is the first posture or the second posture. The calibration device described. Gyro sensor,
At least one of a geomagnetic sensor, an acceleration sensor, and a distance sensor;
A housing in which the gyro sensor and the at least one sensor are mounted and at least two postures are defined;
A processor for obtaining an output value of the gyro sensor and the at least one sensor, and the processor of the calibration device comprising:
Based on the output value of the gyro sensor, a first period when the attitude of the housing is the first attitude and a second period when the attitude of the housing is the second attitude are calculated. 1 step,
A second step of calibrating the at least one sensor based on an output value of the at least one sensor in the first period and the second period;
A program for running

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