TW201944183A - Automatic moving device and avoidance method thereof - Google Patents

Abstract

An automatic moving device and an avoidance method thereof are provided. The autonomous moving device includes a body, a driving wheel, an auxiliary wheel, a distance measuring sensor and a control circuit. The driving wheel, the auxiliary wheel and the distance measuring sensor are arranged on the bottom of the body. The distance measuring sensor detects a distance between the bottom of the body and the ground or a distance between the bottom of the body and an obstacle, and obtains a detection distance. The control circuit is coupled to the driving wheel and the distance measuring sensor, and the control circuit compares the detecting distance with a first preset value. When the detection distance is greater than or equal to the first preset value, the control circuit controls the driving wheel to perform obstacle avoidance, wherein the first preset value has a positive correlation with the radius of the auxiliary wheel.

Description

Autonomous mobile device and its avoiding method

The present invention relates to an electronic device, and more particularly, to an autonomous mobile device and an avoidance method thereof.

Floor cleaning is one of the most frequent tasks in daily cleaning of general indoor environment. In order to reduce human labor burden, many convenient cleaning machines have been invented and marketed. When sweeping the robot on the ground, there are often different obstacles on the ground that will prevent the cleaning, such as cardboard, CD boxes, up stairs, down stairs, etc., which will cause different height differences between the fuselage and the ground, which may cause The cleaning robot is unable to overcome the problem of height difference and complete the cleaning work smoothly.

The invention provides an autonomous mobile device and an avoidance method thereof, which can enable the autonomous mobile device to perform obstacle avoidance more effectively.

The autonomous mobile device of the present invention includes a body, a driving wheel, an auxiliary wheel, a ranging sensor, and a control circuit. The driving wheel, the auxiliary wheel, and the distance measuring sensor are disposed on the bottom of the body. The ranging sensor detects the distance between the bottom of the body and the ground or the distance between the bottom of the body and an obstacle, and obtains the detection distance. The control circuit is coupled to the driving wheel and the ranging sensor. The control circuit compares the detection distance with a first preset value. When the detection distance is greater than or equal to the first preset value, the control circuit controls the driving wheel to avoid obstacles. A preset value is positively related to the radius of the auxiliary wheel.

The invention also provides an avoidance method for an autonomous mobile device, wherein the autonomous mobile device includes a body, a driving wheel, and an auxiliary wheel, and the drive wheel and the auxiliary wheel are disposed at the bottom of the body. The distance between the bottom and the ground or the distance between the bottom of the body and the obstacle, and the detection distance is obtained; and the detection distance is compared with the first preset value, and the control is controlled when the detection distance is greater than or equal to the first preset value The wheel performs obstacle avoidance, wherein the first preset value is positively related to the radius of the auxiliary wheel.

Based on the above, the embodiment of the present invention controls the driving wheel to drive the autonomous mobile device to perform obstacle avoidance based on the detection distance, so that the autonomous mobile device can perform obstacle avoidance more effectively.

In order to make the above features and advantages of the present invention more comprehensible, embodiments are hereinafter described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic diagram of an autonomous mobile device according to an embodiment of the present invention. Please refer to FIG. 1. The autonomous mobile device 100 may be, for example, a sweeping robot or a mopping robot, but is not limited thereto. The autonomous mobile device 100 includes a body 102, a driving wheel 104, an auxiliary wheel 106, a ranging sensor 108, and a control circuit 110. The driving wheels 104 and the auxiliary wheels 106 are disposed on the bottom B of the body 102. The driving wheels 104 and the auxiliary wheels 106 may be implemented as directional wheels, universal wheels or omnidirectional wheels. The driving wheel 104 can be used to drive the autonomous mobile device 100 to move, and the auxiliary wheel 106 can be used to support the autonomous mobile device 100.

Please continue to refer to FIG. 1, the ranging sensor 108 is also disposed on the bottom B of the main body 102. The setting manner of the ranging sensor 108 may be as shown in the embodiment of FIG. 2. In the embodiment of FIG. 2, the autonomous mobile device 100 includes a plurality of ranging sensors 108 disposed near an edge of the body 102. The distance between each ranging sensor 108 and the edge of the body 102 is smaller than the distance between the driving wheel 104 and the auxiliary wheel 106 to the edge of the body 102. In this way, it can be ensured that the ranging sensor 108 detects an obstacle before the auxiliary wheel 106 or the driving wheel 104 moves to the position of the obstacle. It should be noted that the numbers of the driving wheels 104, the auxiliary wheels 106, and the ranging sensors 108 in the illustration are only exemplary embodiments.

As shown in FIG. 1 and FIGS. 4 to 6, the distance measuring sensor 108 can detect the distance between the bottom B of the body 102 and the ground G1 or the distance between the bottom B of the body 102 and the obstacle O, and obtain a detection. Distance (for example: detection distance D1 in FIG. 1, detection distance D2 in FIG. 4, detection distance D3 in FIG. 5, or detection distance D4 in FIG. 6). At this time, the driving wheel 104 is located on the ground G2. In detail, as shown in FIG. 3, the ranging sensor 108 may include a light emitter 302, a light sensor 304, and a processing circuit 306. The processing circuit 306 is coupled to the light transmitter 302 and the light sensor 304. The light transmitter 302 has an emission angle and is used to emit a light beam. The light beam emitted by the light transmitter 302 may be infrared light or other invisible or visible light having different wavelengths. The light sensor 304 has a receiving angle and is configured to sense the reflected light provided by the ground G1 after reflecting the light beam from the light transmitter 302. The processing circuit 306 can calculate the distance between the bottom B of the main body 102 and the ground G1 or the bottom B of the main body 102 and the obstacle O according to the time difference between the light beam emitted by the light transmitter 302 and the reflected light received by the light sensor 304 and the speed of light. In some embodiments, the processing circuit 306 may be implemented as a microprocessor or microcontroller. In some embodiments, the processing circuit 306 and the control circuit 110 may be integrated on the same chip. In some embodiments, the distance between the light emitter 302 and the light sensor 304 is very close. In this way, the detection distance is almost equal to half the length of the entire light path.

In some embodiments, the control circuit 110 is coupled to the driving wheel 104 and the ranging sensor 108. The control circuit 110 may compare the above-mentioned detection distances with the body height H, the first preset value or the second preset value, and decide whether to control the driving wheel 104 to drive the autonomous mobile device 100 for obstacle avoidance according to the comparison result. . In some embodiments, obstacle avoidance includes stopping or turning.

As shown in FIG. 1, when the detection distance D1 is equal to the height H of the fuselage plus an error value (for example, there is no height difference on the ground or there are only tiny holes in the ground), the driving wheel 104 can drive the autonomous mobile device 100 according to the original Move on a predetermined path to clean on the original path. In some embodiments, the fuselage height H is the distance between the bottom B of the body 102 and the ground G2. In some embodiments, the fuselage height H may be known or measured in advance, and the error value may be positive or negative. In some embodiments, the absolute value of the error value is substantially set to be smaller than the radius R of the auxiliary wheel 106 to ensure that the autonomous mobile device 100 can cross an obstacle or avoid being trapped in a deeper hole. As shown in FIG. 4, when the detection distance D2 is greater than or equal to a first preset value (for example, the right-side downward step in the embodiment of FIG. 4 is very low), the control circuit 110 may control the driving wheels 104 to drive the autonomous mobile device 100 to perform Avoid obstacles to prevent the autonomous mobile device 100 from falling. In some embodiments, the first preset value is substantially equal to the body height H of the body 102 plus the radius R of the auxiliary wheel 106. In the above relationship, the first preset value is positively related to the radius R of the auxiliary wheel 106. That is, when the radius R of the auxiliary wheel 106 is larger, the first preset value is also larger accordingly. As shown in FIG. 5, when the detection distance D3 is less than or equal to the second preset value (for example, the step on the right side in the embodiment of FIG. 5 is very high), the control circuit 110 may also control the driving wheel 104 to drive the autonomous mobile device 100. Obstacle avoidance is performed to prevent the autonomous mobile device 100 from hitting the right-up stairs. Since the autonomous mobile device 100 cannot span a height larger than the radius R of the auxiliary wheel 106, the second preset value is substantially set to be equal to the radius R of the auxiliary wheel 106. In addition, when the detection distance D2 or D3 is smaller than the first preset value and larger than the second preset value, the control circuit 110 may not need to control the driving wheel 104 to drive the autonomous mobile device 100 to avoid it. That is, the control circuit 110 can control the autonomous mobile device 100 to move according to the original path, and adjust the moving speed or acceleration of the autonomous mobile device 100 according to circumstances.

Similarly, in the embodiment of FIG. 6, when the detection distance D4 is less than or equal to the second preset value (for example, the height of the obstacle O in the embodiment of FIG. 6 is high), the control circuit 110 may also control the driving wheels 104. The autonomous mobile device 100 is driven to perform obstacle avoidance to prevent the autonomous mobile device 100 from hitting the obstacle O. In addition, when the detection distance D4 is smaller than the first preset value and larger than the second preset value, the control circuit 110 may not need to control the driving wheel 104 to drive the autonomous mobile device 100 to avoid it. That is, the control circuit 110 can control the autonomous mobile device 100 to move according to the original path, and adjust the moving speed or acceleration of the autonomous mobile device 100 according to circumstances.

In this way, according to the relationship between the detection distance and the radius R of the auxiliary wheel 106, it is more effective to control the driving wheel 104 to drive the autonomous mobile device 100 to avoid obstacles, instead of judging whether to avoid or not based on whether the floor is detected or not, as in conventional technology To avoid obstacles. Generally, the radius R of the auxiliary wheel 106 is smaller than the radius of the driving wheel 104. Therefore, whether to avoid obstacles is determined based on the relationship between the detection distance and the radius R of the auxiliary wheel 106, instead of using the radius of the driving wheel 104. The decision can make the conditions for determining whether to avoid obstacle avoidance more accurate, so as to take into account both the cleaning task and the protection of the autonomous mobile device 100. In addition, the ranging sensor 108 of the above embodiment has a smaller volume than the cliff sensor used in the conventional technology, which can be beneficial to the miniaturization of the autonomous mobile device 100.

As mentioned in the previous paragraph, in some embodiments, when the detection distance is less than the first preset value and greater than the second preset value, the control circuit 110 may control the driving wheel 104 to adjust the autonomous mobile device 100 according to the detection distance. Movement speed or acceleration. For example, the control circuit 110 may reduce the moving speed or acceleration of the autonomous mobile device 100 in response to an increase in the detection distance. For example, when the detection distance D2 in FIG. 4 is larger, it means that the right downward step in the embodiment in FIG. 4 is lower. At this time, the speed of the autonomous mobile device 100 needs to be slowed down to avoid the main mobile device 100 from moving. Crash due to excessive vibration when passing through the steps. Or when the detection distance D3 in FIG. 5 is larger or the detection distance D4 in FIG. 6 is larger, it means that the step on the right side in the embodiment of FIG. 5 is lower or the height of the obstacle O in FIG. 6 is lower. The control circuit 110 can make the autonomous mobile device 100 easily cross the obstacle without greatly increasing the moving speed or acceleration of the autonomous mobile device 100.

In some other embodiments, the autonomous mobile device 100 may further include a camera device 109 coupled to the control circuit 110. The control circuit 110 may determine a moving speed of the autonomous mobile device 100 according to an image captured by the imaging device 109. For example, when the autonomous mobile device 100 is applied to a cleaning robot, the control circuit 110 may determine the ground condition according to the image captured by the camera device 109 and adjust the moving speed of the autonomous mobile device 100 accordingly. The ground condition may be, for example, the material of the ground G1 and the dirt condition. When the material of the ground G1 is difficult to clean or the dirt is more serious, the control circuit 110 may control the driving wheels 104 to drive the autonomous mobile device 100 to move at a slower speed to enhance the cleaning of the ground G1.

For ease of understanding, the following paragraphs take the autonomous mobile device 100 as an example for illustration, but not limited thereto. FIG. 7 is a flowchart of an avoidance method of an autonomous mobile device 100 according to an embodiment of the present invention. Please refer to FIG. 7. It can be known from the above embodiments that the steps of the avoidance method of the autonomous mobile device 100 may include at least the following steps. First, in step S702, the distance between the bottom B of the body 102 and the ground G1 or the distance between the bottom B of the body 102 and the obstacle O is detected, and a detection distance is obtained (for example, the detection distance D1 in FIG. 1). , Detection distance D2 in FIG. 4, detection distance D3 in FIG. 5 or detection distance D4 in FIG. 6). Next, in step S704, it is determined whether the detection distance is equal to the body height H plus an error value. Then, in step S706, it is determined whether the detection distance is greater than or equal to a first preset value. If the detection distance is greater than or equal to the first preset value, the process proceeds to step S708. In step S708, the driving wheels 104 are controlled to drive the autonomous mobile device 100 to avoid obstacles. In some embodiments, the first preset value is positively related to the radius R of the auxiliary wheel 106. The first preset value may be substantially equal to the body height H of the body 102 plus the radius R of the auxiliary wheel 106. Conversely, if the detection distance is not greater than or equal to the first preset value, the process proceeds to step S710. In step S710, it is determined whether the detection distance is less than or equal to a second preset value. In some embodiments, the second preset value is substantially equal to the radius R of the auxiliary wheel 106. If the detection distance is less than or equal to the second preset value, the process proceeds to step S708. In step S708, the driving wheels 104 are controlled to drive the autonomous mobile device 100 to avoid obstacles. If the detection distance is between the first preset value and the second preset value, the process returns to step S702. That is, at this time, it is not necessary to control the driving wheel 104 to drive the autonomous mobile device 100 to avoid, and continue to detect the distance between the bottom B of the body 102 and the ground G1.

FIG. 8 is a flowchart of an avoidance method of an autonomous mobile device 100 according to another embodiment of the present invention. Please refer to FIG. 8. The avoidance method of the autonomous mobile device 100 of this embodiment is different from the embodiment of FIG. 6 in that the avoidance method of the autonomous mobile device 100 of this embodiment further includes step S802. When the determination in step S710 is NO, it proceeds to step S802. That is, when the detection distance is between the first preset value and the second preset value, the driving wheel 104 can be controlled according to the detection distance to adjust the moving speed or acceleration of the autonomous mobile device 100. For example, the moving speed or acceleration of the autonomous mobile device 100 is reduced corresponding to an increase in the detection distance, so as to avoid an abnormal situation of the autonomous mobile device 100 or to enable the autonomous mobile device 100 to cross an obstacle more easily. Then, it returns to step S702 to continue detecting the distance between the bottom B of the body 102 and the ground G1. In addition, in some implementations, the moving speed or acceleration of the autonomous mobile device 100 may also be adjusted according to ground conditions. The ground condition can be obtained by photographing the ground G1 with the camera 109, and the ground condition can include the material of the ground G1 and the dirt condition.

In summary, the present invention controls the driving wheel to drive the autonomous mobile device to perform obstacle avoidance based on the detection distance, instead of judging whether to avoid based on whether the floor is detected or not, as in the conventional technology, the autonomous action can be controlled more effectively The device performs obstacle avoidance. In some embodiments, the driving wheel can be controlled to adjust the movement speed or acceleration of the autonomous mobile device according to the detection distance, so as to avoid an abnormal situation of the autonomous mobile device, or enable the autonomous mobile device to cross obstacles more easily.

Although the present invention has been disclosed as above with the examples, it is not intended to limit the present invention. Any person with ordinary knowledge in the technical field can make some modifications and retouching without departing from the spirit and scope of the present invention. The protection scope of the present invention shall be determined by the scope of the attached patent application.

100‧‧‧ autonomous mobile device

102‧‧‧ Ontology

104‧‧‧Drive Wheel

106‧‧‧ auxiliary wheel

108‧‧‧ ranging sensor

109‧‧‧ Camera

110‧‧‧Control circuit

302‧‧‧light transmitter

304‧‧‧light sensor

306‧‧‧Processing Circuit

B‧‧‧ bottom

D1 ~ D4‧‧‧ Detection distance

G1, G2‧‧‧ Ground

H‧‧‧body height

R‧‧‧ radius

O‧‧‧ obstacle

S702 ~ S710, S802‧‧‧ steps

FIG. 1 is a schematic diagram of an autonomous mobile device according to an embodiment of the present invention. FIG. 2 is a schematic diagram of a bottom portion of a main body of an autonomous mobile device according to an embodiment of the present invention. 3 is a schematic diagram of distance detection performed by a ranging sensor according to an embodiment of the present invention. FIG. 4 is a schematic diagram of detecting a ground condition by an autonomous mobile device according to an embodiment of the present invention. FIG. 5 is a schematic diagram of detecting a ground condition by an autonomous mobile device according to another embodiment of the present invention. FIG. 6 is a schematic diagram of detecting obstacles by an autonomous mobile device according to another embodiment of the present invention. FIG. 7 is a flowchart of an avoidance method of an autonomous mobile device according to an embodiment of the present invention. FIG. 8 is a flowchart of an avoidance method of an autonomous mobile device according to another embodiment of the present invention.

Claims (13)

An autonomous mobile device includes: a body; a driving wheel provided at the bottom of the body; an auxiliary wheel provided at the bottom of the body; a distance measuring sensor provided at the bottom of the body; The detector detects the distance between the bottom of the body and a ground or the distance between the bottom of the body and an obstacle, and obtains a detection distance; and a control circuit, which is coupled to the driving wheel and the distance sensing The control circuit compares the detection distance with a first preset value, and when the detection distance is greater than or equal to the first preset value, the control circuit controls the driving wheel for obstacle avoidance, wherein the first preset The value is positively related to the radius of this auxiliary wheel. The autonomous mobile device according to item 1 of the scope of patent application, wherein the first preset value is substantially equal to the body height of the body plus the radius of the auxiliary wheel. The autonomous mobile device according to item 2 of the scope of patent application, wherein the control circuit compares the detection distance with a second preset value, and when the detection distance is less than or equal to the second preset value, the control circuit controls The driving wheel performs obstacle avoidance, wherein the second preset value is substantially equal to a radius of the auxiliary wheel. The autonomous mobile device according to item 3 of the scope of patent application, wherein when the detection distance is less than the first preset value and greater than the second preset value, the control circuit controls the driving wheel to adjust according to the detection distance The speed or acceleration of the autonomous mobile device. The autonomous mobile device according to item 4 of the scope of patent application, wherein the control circuit reduces the moving speed or acceleration of the autonomous mobile device in response to an increase in detection distance. The autonomous mobile device according to item 1 of the scope of patent application, further comprising: a camera device coupled to the control circuit, the control circuit determines the ground condition based on the image of the ground captured by the camera device, and adjusts the ground condition according to the ground condition The moving speed of the autonomous mobile device, wherein the ground condition includes the material of the ground and the dirt condition. The autonomous mobile device according to item 1 of the scope of patent application, wherein the ranging sensor comprises: a light transmitter that emits a light beam; a light sensor that senses a reflected light provided by the ground after receiving the light beam; And a processing circuit coupled to the light transmitter, the light sensor and the control circuit, the processing circuit calculates the detection based on a time difference between the light transmitter emitting the light beam and the light sensor receiving the reflected light distance. An avoidance method for an autonomous mobile device. The autonomous mobile device includes a body, a drive wheel, and an auxiliary wheel. The drive wheel and the auxiliary wheel are disposed at the bottom of the body. The avoidance method of the autonomous mobile device includes: detecting the The distance between the bottom of the body and a ground or the distance between the bottom of the body and an obstacle to obtain a detection distance; and comparing the detection distance with a first preset value when the detection distance is greater than or equal to When the first preset value is used, the driving wheel is controlled to avoid obstacles. The first preset value is positively related to the radius of the auxiliary wheel. The method for avoiding an autonomous mobile device according to item 8 of the scope of patent application, wherein the first preset value is substantially equal to the body height of the body plus the radius of the auxiliary wheel. The method for avoiding an autonomous mobile device according to item 9 of the scope of patent application, further comprising: comparing the detection distance with a second preset value, and controlling the detection distance when the detection distance is less than or equal to the second preset value. The driving wheel performs obstacle avoidance, wherein the second preset value is substantially equal to a radius of the auxiliary wheel. The avoidance method for an autonomous mobile device according to item 10 of the scope of patent application, wherein when the detection distance is less than the first preset value and greater than the second preset value, the driving wheel is adjusted according to the detection distance The speed or acceleration of the autonomous mobile device. The method for avoiding an autonomous mobile device according to item 11 of the scope of patent application includes: reducing the moving speed or acceleration of the autonomous mobile device in response to an increase in the detection distance. The method for avoiding the autonomous mobile device according to item 8 of the scope of patent application, further comprising: shooting an image of the ground; judging the ground condition based on the captured image of the ground; and adjusting the autonomous mobile device according to the ground condition. Movement speed, where the ground condition includes the material of the ground and the dirt condition.