JP2015103227A - Autonomous mobile body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce unnecessary stop of an autonomous mobile body.SOLUTION: An autonomous mobile body comprises: driving means for moving a mobile body; a sensor unit that faces a road surface in a moving direction of the autonomous mobile body and includes at least three distance sensors for detecting a distance to an object being in a same area; and control means that, when the distance to the object detected by each of the distance sensors of the sensor unit exceeds a threshold value, controls the driving means so that the autonomous mobile body is decelerated or avoids the object. The control means, when only one distance of distances detected by the at least three distance sensors of the sensor unit exceeds the threshold value or only one distance does not exceed the threshold value, controls the driving means on the basis of determining whether or not the other distances other than the one distance exceed the threshold value.

Description

  The present invention relates to an autonomous mobile body that moves autonomously.

  In recent years, various autonomous moving bodies that detect obstacles such as steps using sensors and move autonomously are known. For example, there is known an autonomous mobile body that detects a distance to the floor surface in the traveling direction by a distance sensor and autonomously avoids traveling when there is a step when the detected distance exceeds a threshold value. (See Patent Document 1).

JP 2012-130781 A

  However, in the autonomous mobile body, when the distance sensor fails, the avoidance operation is not performed and a problem such as being stuck in a step may occur. On the other hand, when two distance sensors are provided and only one of the distances detected by each distance sensor exceeds the threshold and the distance is different between the two distance sensors, an abnormality of either one of the distance sensors is detected. The structure to judge can be considered. In the case of this configuration, it cannot be determined which distance sensor is abnormal, and it cannot be determined whether a step or the like actually exists. Therefore, for example, even when there is no step or the like and there is a floor surface, when the distance detected by one of the distance sensors exceeds a threshold value, the autonomous mobile body is controlled to stop. . For this reason, since the autonomous mobile body originally stopped at a place where it is not necessary to stop, there has been a problem of performing an unnecessary stop such as stopping in the middle of the passage.

  The present invention has been made to solve such problems, and a main object of the present invention is to provide an autonomous mobile body that can reduce unnecessary stops.

One aspect of the present invention for achieving the above object is to detect at least the distance between the driving means for moving the autonomous mobile body and the object in the same region that is directed to the road surface in the moving direction of the autonomous mobile body. When the distance between a sensor unit including three distance sensors and an object detected by each distance sensor of the sensor unit exceeds a threshold, the driving unit is configured to decelerate the autonomous mobile body or avoid the object. An autonomous moving body comprising: a control means for controlling, wherein the control means includes a distance detected by at least three distance sensors of the sensor unit, wherein only one distance exceeds the threshold value. Or, when only one distance does not exceed the threshold, the control of the driving means is performed based on the determination of whether another distance other than the one distance exceeds the threshold. It is an autonomous mobile body characterized by
In this one aspect, the sensor unit combines n + 1 distance sensors from the 2n + 1 distance sensors, and a plurality of AND circuits to which output signals of the combined n + 1 distance sensors are respectively input, A first determination means having a logical sum circuit to which a signal indicating the operation result of the logical product circuit is input, and the presence or absence of the object is determined based on the signal indicating the operation result of the logical sum circuit Good.
In this aspect, the sensor unit further includes second determination means having 2n + 1 exclusive OR circuits corresponding to the 2n + 1 distance sensors, and each of the exclusive OR circuits includes the corresponding distance. An exclusive OR operation is performed based on the output signal from the sensor and the output signal output from the first determination means, and abnormality of each distance sensor is individually determined based on the calculation result Good.
In this aspect, the sensor unit includes first to third distance sensors, and the first determination means includes a first AND circuit to which output signals of the first and second distance sensors are input, A second AND circuit to which the output signals of the second and third distance sensors are input; a third AND circuit to which the output signals of the first and third distance sensors are input; and the first to third logics. And an OR circuit to which an output signal of the product circuit is input.
In this aspect, the second determination unit includes first to third exclusive OR circuits corresponding to the first to third distance sensors, respectively, and the first exclusive OR circuit includes: An exclusive OR operation is performed based on the output signal of the third distance sensor and the output signal of the OR circuit of the first determination means, the abnormality of the third distance sensor is identified, and the second exclusive logic The sum circuit performs an exclusive OR operation based on the output signal of the second distance sensor and the output signal of the OR circuit of the first determination means, identifies an abnormality of the second distance sensor, and 3. The exclusive OR circuit performs an exclusive OR operation based on the output signal of the first distance sensor and the output signal of the OR circuit of the first determination means, and identifies an abnormality of the first distance sensor. May be.
In this aspect, the sensor unit includes first to fifth distance sensors, and the first determination means includes a first AND circuit to which output signals of the first to third distance sensors are input, A second AND circuit to which the output signals of the first, second and fourth distance sensors are input; a third AND circuit to which the output signals of the first, second and fifth distance sensors are input; A fourth AND circuit to which the output signals of the first, third and fourth distance sensors are input; a fifth AND circuit to which the output signals of the first, third and fifth distance sensors are input; A sixth AND circuit to which the output signals of the first, fourth and fifth distance sensors are input; a seventh AND circuit to which the output signals of the second to fourth distance sensors are input; and the second , An eighth AND circuit to which the output signals of the third and fifth distance sensors are input, and the second A ninth AND circuit to which the output signals of the fourth and fifth distance sensors are input; a tenth AND circuit to which the output signals of the third to fifth distance sensors are input; and the first to tenth logics. And an OR circuit to which an output signal of the product circuit is input.
In this aspect, the second determination unit includes first to fifth exclusive OR circuits corresponding to the first to fifth distance sensors, respectively, and the first exclusive OR circuit includes: An exclusive OR operation is performed based on the output signal of the first distance sensor and the output signal of the OR circuit of the first determination means, the abnormality of the first distance sensor is specified, and the second exclusive logic The sum circuit performs an exclusive OR operation based on the output signal of the second distance sensor and the output signal of the OR circuit of the first determination means, identifies an abnormality of the second distance sensor, and The 3 exclusive OR circuit performs an exclusive OR operation based on the output signal of the third distance sensor and the output signal of the OR circuit of the first determination means, and identifies an abnormality of the third distance sensor. And the fourth exclusive OR circuit includes the fourth distance sensor. An exclusive OR operation is performed based on the output signal and the output signal of the OR circuit of the first determination means, the abnormality of the fourth distance sensor is specified, and the fifth exclusive OR circuit An abnormality of the fifth distance sensor may be specified by performing an exclusive OR operation based on the output signal of the 5-distance sensor and the output signal of the OR circuit of the first determination means.

  ADVANTAGE OF THE INVENTION According to this invention, providing the autonomous mobile body which can reduce an unnecessary stop can be provided.

1 is a block diagram illustrating a system configuration of an object detection device according to Embodiment 1. FIG. 1 is a block diagram showing a system configuration of an autonomous mobile body according to Embodiment 1. FIG. 1 is a block diagram showing a system configuration of an autonomous mobile body according to Embodiment 1. FIG. 1 is a block diagram showing a system configuration of an autonomous mobile body according to Embodiment 1. FIG. 1 is a block diagram showing a system configuration of an autonomous mobile body according to Embodiment 1. FIG. 1 is a block diagram showing a system configuration of an autonomous mobile body according to Embodiment 1. FIG. 1 is a block diagram showing a system configuration of an autonomous mobile body according to Embodiment 1. FIG. 6 is a block diagram illustrating a system configuration of an object detection device according to Embodiment 2. FIG.

Embodiment 1
Embodiments of the present invention will be described below with reference to the drawings. The autonomous mobile body according to Embodiment 1 of the present invention includes, for example, an object detection device 10 that can detect a steep step such as a staircase or an object such as a floor surface. The autonomous mobile body according to Embodiment 1 can travel autonomously on the detected floor surface while avoiding the step detected by the object detection device 10. FIG. 1 is a block diagram showing a schematic system configuration of the object detection apparatus according to Embodiment 1 of the present invention. The object detection device 10 is a specific example of a sensor unit, and includes first to third distance sensors 1, 2, and 3, a first determination circuit 4, and a second determination circuit 5.

  The first to third distance sensors 1, 2, and 3 are directed to the road surface in the moving direction of the autonomous mobile body, and detect the distance from an object in the same region. For example, the first to third distance sensors 1, 2, and 3 are respectively provided on the front side of the autonomous mobile body, and detect an object that exists in the forward direction of the autonomous mobile body. In addition, the first to third distance sensors 1, 2, and 3 may be provided on the rear side of the autonomous mobile body and detect an object that exists in the backward direction of the autonomous mobile body. Alternatively, the first to third distance sensors 1, 2, and 3 may be provided on the front side and the rear side of the autonomous mobile body, respectively, and may detect an object that exists in the forward direction and the reverse direction of the autonomous mobile body. In addition, when the autonomous mobile body is movable in all directions, the first to third distance sensors 1, 2, and 3 are provided in all directions of the autonomous mobile body, respectively. An existing object may be detected.

  Furthermore, it is preferable that at least a part of the detection areas of the first to third distance sensors 1, 2, and 3 overlap. The detection areas of two sensors among the first to third distance sensors 1, 2, and 3 are overlapped, or the detection areas of the first to third distance sensors 1, 2, and 3 are also overlapped. It does not have to be. By overlapping the detection areas of the first to third distance sensors 1, 2, and 3, the accuracy of determination results of first and second determination circuits 4 and 5 described later increases.

  The 1st thru | or 3rd distance sensors 1, 2, and 3 are comprised by the ultrasonic sensor, the infrared sensor, the visible light sensor, the ultraviolet sensor, etc. In addition, although the 1st thru | or 3rd distance sensors 1, 2, and 3 are comprised by the sensor of the said same system, it may comprise not only this but combining the sensor of a different system. For example, the first distance sensor 1 may be an ultrasonic sensor, the second distance sensor 2 may be an infrared sensor, and the third distance sensor 3 may be a visible light sensor.

  When the 1st thru | or 3rd distance sensors 1, 2, and 3 are comprised by the sensor of the same system, robustness improves about the measurement area | region. On the other hand, when the first to third distance sensors 1, 2, and 3 are composed of different types of sensors, it is possible to secure a wider measurement area that cannot be covered by a single sensor method.

  The first to third distance sensors 1, 2, and 3 may be configured by arbitrarily combining two-dimensional distance sensors such as a laser range finder (Time of Flight method, phase difference method), for example. The first to third distance sensors 1, 2, and 3 may be configured by arbitrarily combining three-dimensional distance sensors such as an RGB-D camera, a stereo camera, and a laser scanning sensor, for example. Further, the first to third distance sensors 1, 2, and 3 may be configured by arbitrarily combining one-dimensional to three-dimensional distance sensors.

  The first to third distance sensors 1, 2, and 3 detect objects such as a floor surface and a step. When the first to third distance sensors 1, 2, and 3 detect an object within a predetermined distance, the first and second determinations are made on the signal “1” that indicates a true value that the object is a floor surface on which the object can travel. Output to circuits 4 and 5. On the other hand, when the first to third distance sensors 1, 2, and 3 detect an object that is longer than a predetermined distance, the first signal “0” that indicates a false value is assumed to be a falling surface of a step that cannot travel. And output to the second determination circuits 4 and 5. As described above, the first determination circuit 4 can identify the floor surface that can travel and the drop surface of the step that cannot travel based on the output values of the first to third distance sensors 1, 2, and 3. Based on the output signal of the first determination circuit 4, the moving body can travel safely on the floor surface while avoiding the step.

  The object detection apparatus 10 according to the first embodiment is configured to include three first to third distance sensors, but is not limited to this, and 2n + 1 (n = 1, 2, 3,... It is sufficient if the distance sensor is provided with an odd number of distance sensors.

  The first determination circuit 4 determines the presence / absence of an object based on the majority result of the output signals of the first to third distance sensors 1, 2, and 3. For this reason, even if any one of the first to third distance sensors 1, 2, and 3 is abnormal (sensor failure, sensor malfunction due to dust, dust, etc.), The presence / absence of an object can be accurately determined from the output signal of a normal distance sensor.

  The first determination circuit 4 is configured such that when only one distance exceeds the predetermined distance among the distances detected by the first to third distance sensors 1, 2, and 3, or only one distance has the predetermined distance. If not, it is determined whether other distances other than the one distance exceed a predetermined threshold. In this way, the first determination circuit 4 finally determines according to a number of distances (in this case, the distance between two identical distance sensors) among the distances detected by the first to third distance sensors 1, 2, and 3. The presence or absence of an object is determined. The first determination circuit 4 includes first to third logical product circuits (AND circuits) 41, 42, 43 and an OR circuit (OR circuit) 44.

  The first AND circuit 41 is connected to first and second distance sensors 1 and 2, respectively. The first AND circuit 41 performs an AND operation based on signals output from the first and second distance sensors 1 and 2. The first logical product circuit 41 outputs the logical product operation result to the logical sum circuit 44. The second AND circuit 42 is connected with the second and third distance sensors 2 and 3, respectively. The second AND circuit 42 performs an AND operation based on signals output from the second and third distance sensors 2 and 3. The second logical product circuit 42 outputs the logical product operation result to the logical sum circuit 44. The third AND circuit 43 is connected to the first and third distance sensors 1 and 3, respectively. The third AND circuit 43 performs an AND operation based on signals output from the first and third distance sensors 1 and 3. The third logical product circuit 43 outputs the logical product operation result to the logical sum circuit 44.

  The logical sum circuit 44 performs a logical sum operation based on the logical product operation result signal ("0" or "1") output from the first to third logical product circuits 41, 42, and 43. When the signal “1” is output from the OR circuit 44, the first determination circuit 4 determines that an object within a predetermined distance exists (the floor surface exists). For example, the autonomous mobile body autonomously travels on the floor surface determined by the first determination circuit 4.

On the other hand, when the signal “0” is output from the OR circuit 44, the first determination circuit 4 determines that there is an object of a predetermined distance or more (no floor surface, and a stepped surface). To do. For example, the autonomous mobile body travels autonomously while avoiding the step determined by the first determination circuit 4. The logical sum circuit 44 outputs a logical sum operation result signal (“0” or “1”) to the second determination circuit 5.
For example, a plurality (for example, two or three) of the object detection devices 10 configured as described above are arranged on the forward side of an autonomous mobile body that mainly moves forward. Thereby, the level | step difference of a forward direction is detected correctly and the fall and fall of an autonomous mobile body can be prevented reliably. In the case of an autonomous mobile body that moves forward and backward, a plurality of object detection devices 10 may be arranged on the forward and backward sides of the autonomous mobile body. Furthermore, in the case of an autonomous mobile body that can move in all directions, a plurality of (for example, eight) object detection devices 10 may be arranged along the outer periphery of the autonomous mobile body. Thereby, the level | step difference of all directions can be detected correctly and the fall and fall of an autonomous mobile body can be prevented reliably.

  By the way, in an autonomous mobile body (in particular, an inverted mobile body that travels while maintaining an inverted state), even if an abnormality occurs in the distance sensor, the floor surface or a step is always detected accurately and the abnormality is detected. It is important to quickly identify and deal with the cause. On the other hand, as described above, the autonomous mobile body according to the first embodiment can accurately detect an object even when any of the first to third distance sensors 1, 2, and 3 is abnormal. At the same time, it is possible to quickly and accurately specify which of the first to third distance sensors 1, 2, and 3 is abnormal. Therefore, the autonomous mobile body can continue to move so as to avoid the object that is decelerated or detected based on the distance detected by the normal distance sensor. For this reason, the autonomous mobile body does not have a problem of stopping at a place where it is not necessary to stop, and can reduce unnecessary stops.

  The second determination circuit 5 is based on the determination result of the first determination circuit 4 and the output signals from the first to third distance sensors 1, 2, 3. Judge abnormalities individually. As described above, the first determination circuit 4 can accurately detect the presence / absence of an object without erroneous detection even when an abnormality occurs in any of the first to third distance sensors 1, 2, and 3. . Furthermore, at the same time, the second determination circuit 5 can specify which of the first to third distance sensors 1, 2, and 3 is abnormal.

  The second determination circuit 5 includes first to third exclusive OR circuits (XOR circuits) 51, 52, and 53 corresponding to the first to third distance sensors 1, 2, and 3. The first exclusive OR circuit 51 is connected to the OR circuit 44 of the first determination circuit 4 and the third distance sensor 3. The first exclusive OR circuit 51 performs an exclusive OR operation on the basis of signals output from the OR circuit 44 of the first determination circuit 4 and the third distance sensor 3, and a signal (“0”) of the operation result is obtained. Or “1”).

  The second exclusive OR circuit 52 is connected to the OR circuit 44 of the first determination circuit 4 and the second distance sensor 2. The second exclusive OR circuit 52 performs an exclusive OR operation based on signals output from the OR circuit 44 of the first determination circuit 4 and the second distance sensor 2, and outputs the operation result.

  The third exclusive OR circuit 53 is connected to the OR circuit 44 of the first determination circuit 4 and the first distance sensor 1. The third exclusive OR circuit 53 performs an exclusive OR operation based on signals output from the OR circuit 44 of the first determination circuit 4 and the first distance sensor 1, and outputs the operation result.

  For example, when the operation result signal output from the first exclusive OR circuit 51 is “1”, the second determination circuit 5 determines that the third distance sensor 3 is abnormal. The second determination circuit 5 determines that the second distance sensor 2 is abnormal when the calculation result signal output from the second exclusive OR circuit 52 is “1”. The second determination circuit 5 determines that the first distance sensor 1 is abnormal when the calculation result signal output from the third exclusive OR circuit 53 is “1”.

  As described above, the second determination circuit 5 can individually determine the abnormality of the first to third distance sensors 1, 2, and 3 based on the output signals of the first to third exclusive logic circuits 51, 52, and 53. . The object detection apparatus according to the first embodiment can be realized with a simple configuration including only the first sensor and the second determination circuit including the distance sensor and the electronic circuit. It also leads to reduction.

Next, the processing flow of the object detection apparatus according to the first embodiment will be described in detail.
The first to third distance sensors 1, 2, and 3 detect the floor and send signals indicating the detection results to the first to third AND circuits 41, 42, 43 and the second determination circuit of the first determination circuit 4. 5 to the first to third exclusive OR circuits 51, 52 and 53 (step S101). The first to third AND circuits 41, 42, and 43 of the first determination circuit 4 perform an AND operation based on the output signals output from the first to third distance sensors 1, 2, and 3 (step S102). ), And outputs a signal indicating the calculation result to the OR circuit 44 of the first determination circuit 4.

  The logical sum circuit 44 of the first determination circuit 1 performs a logical sum operation based on the signals output from the first to third logical product circuits 41, 42, and 43 (step S103), and outputs a signal indicating the result of the operation. It outputs to the control apparatus 6 which controls the movement of an autonomous mobile body (FIG. 2). The control device 6 controls the movement of the autonomous mobile body based on the signal output from the logical sum circuit 44 of the first determination circuit 4 (step S104).

  The first to third exclusive OR circuits 51, 52, and 53 of the second determination circuit 3 perform exclusive OR operation based on signals output from the first to third distance sensors 1, 2, and 3. (Step S105), a signal indicating the calculation result is output. The warning device 7, for example, uses the first to third distance sensors 1, 2, 3 of the second determination circuit 5 based on signals output from the first to third exclusive OR circuits 51, 52, 53. Which distance sensor is abnormal is displayed to the user and a warning is given (step S106).

  The warning device 7 is configured as a display device that displays which of the first to third distance sensors 1, 2, and 3 is abnormal. It may be an output device, a vibration device that is sensed by vibration, or a communication device that remotely notifies a user.

  FIG. 3 is a block diagram showing a schematic system configuration of the autonomous mobile body according to the first embodiment. The autonomous mobile body 11 according to the first embodiment includes three object detection devices 10, a drive device 12 that drives wheels and the like to travel the autonomous mobile body 11, and a drive power source that supplies power to the drive device 12. 13, a relay circuit 14, a control power supply 15 that supplies power to the control device 6, a control device 6 that controls driving of the drive device, an inverting circuit 16, and an AND circuit 18.

  The first determination circuit 4 of each object detection device 10 outputs a signal “1” to the logical product circuit 18 when the floor surface is detected. The logical product circuit 18 performs a logical product operation based on the signal “1” from each object detection device 10 and outputs a signal “1” to the inverting circuit 16. The inverting circuit 16 outputs a signal “0” obtained by inverting the signal “1” from the AND circuit 18 to the relay circuit 14.

  On the other hand, the first determination circuit 4 of each object detection device 10 outputs a signal “0” to the logical product circuit 18 when detecting the stepped surface. The logical product circuit 18 performs a logical product operation based on the signal “0” from each object detection device 10 and outputs a signal “0” to the inverting circuit 16. The inverting circuit 16 outputs a signal “1” obtained by inverting the signal “0” from the AND circuit 18 to the relay circuit 14. In response to this signal “1”, the relay circuit 14 switches a built-in relay switch to cut off power supplied from the drive power supply 13 to the drive device 12. Thus, when the object detection device 10 detects a stepped surface, power is cut off to the drive device 12, and the autonomous mobile body 11 is forcibly stopped. Thereby, the autonomous mobile body 11 can stop safely, without falling from a floor surface.

  A brake device 17 that brakes the drive of the drive device 12 may be connected to the first determination circuit 4 of each object detection device 10 via the AND circuit 18 and the inverting circuit 16 (FIG. 4). When the first determination circuit 4 of each object detection device 10 detects the stepped surface, the braking device 17 outputs the first determination circuit 4 of each object detection device 10 via the AND circuit 18 and the inverting circuit 16. In response to the signal “1”, the driving of the driving device 12 is braked, and the autonomous mobile body 11 is decelerated and stopped.

  The configuration may be such that the control device 6 is directly connected to the first determination circuit 4 of the object detection device 10 via the AND circuit 18 (FIG. 5). The first determination circuit 4 of each object detection device 10 outputs a signal “0” to the control device 6 when detecting the stepped surface. The control device 6 controls switching of the relay switch of the relay circuit 14 in accordance with the signal “0” from the first determination circuit 4 of each object detection device 10, and the power supplied from the drive power supply 13 to the drive device 12. Shut off. The control device 6 controls the braking device 17 according to the signal “0” from the first determination circuit 4 of each object detection device 10 to brake the driving device 12 and stop the autonomous mobile body 11. (FIG. 6). Further, the control device 6 controls the driving device 12 in accordance with the signal “0” from the first determination circuit 4 of each object detection device 10, so that the autonomous mobile body 11 is made to avoid the detected step. It may be configured to run (FIG. 7). In addition, in the said Embodiment 1, although the autonomous mobile body 11 is a structure provided with the three object detection apparatuses 10, it is not restricted to this, For example, the structure provided with 1 or 4 or more may be sufficient.

  As described above, in the autonomous mobile body 11 according to the first embodiment, the first determination circuit 4 determines the final object according to many distances among the distances detected by the first to third distance sensors 1, 2, and 3. Judgment is made. Accordingly, even when any one of the first to third distance sensors 1, 2, and 3 is abnormal, the presence or absence of an object can be accurately determined based on the distances of many other normal distance sensors. Therefore, the autonomous mobile body 11 can continue the movement such as the avoidance operation and the deceleration operation based on the distance detected by the normal distance sensor. For this reason, the autonomous mobile body 11 does not have a problem of stopping at a place where it is not necessary to stop, and can reduce unnecessary stops.

Embodiment 2
The object detection device 10 according to the first embodiment has a configuration including the three first to third distance sensors 1, 2, and 3, but the object detection device 20 according to the second embodiment has five fifth detection devices. 1 to 5th distance sensors 21-25 are provided.

  FIG. 8 is a block diagram showing a schematic system configuration of the object detection apparatus according to Embodiment 2 of the present invention. The object detection apparatus 20 according to the second embodiment includes first to fifth distance sensors 21 to 25, a first determination circuit 26, and a second determination circuit 27.

  The first determination circuit 26 includes first to tenth AND circuits 260 to 269 and an OR circuit 259. The first to third distance sensors 21 to 23 are connected to the first AND circuit 261, respectively. The first AND circuit 261 performs an AND operation based on signals output from the first to third distance sensors 21 to 23. The first AND circuit 261 outputs the AND operation result to the OR circuit 259. The first AND circuit 262 is connected to the first, second, and fourth distance sensors 21, 22, and 24, respectively. The second AND circuit 262 performs an AND operation based on signals output from the first, second, and fourth distance sensors 21, 22, and 24. The second AND circuit 262 outputs the AND operation result to the OR circuit 259.

  The first AND circuit 263 is connected to the first, second and fifth distance sensors 21, 22, 25. The third AND circuit 263 performs an AND operation based on signals output from the first, second, and fifth distance sensors 21, 22, and 25. The third AND circuit 263 outputs the AND operation result to the OR circuit 259. The fourth AND circuit 264 is connected to the first, third, and fourth distance sensors 21, 23, and 24, respectively. The fourth logical product circuit 264 performs a logical product operation based on signals output from the first, third, and fourth distance sensors 21, 23, and 24. The fourth logical product circuit 264 outputs the logical product operation result to the logical sum circuit 259.

  The fifth AND circuit 265 is connected to the first, third, and fifth distance sensors 21, 23, and 25, respectively. The fifth AND circuit 265 performs an AND operation based on signals output from the first, third, and fifth distance sensors 21, 23, and 25. The fifth AND circuit 265 outputs the AND operation result to the OR circuit 259. The sixth AND circuit 266 is connected to the first, fourth, and fifth distance sensors 21, 24, and 25, respectively. The sixth AND circuit 266 performs an AND operation based on signals output from the first, fourth and fifth distance sensors 21, 24 and 25. The sixth logical product circuit 266 outputs the logical product operation result to the logical sum circuit 259.

  Second to fourth distance sensors 22 to 24 are connected to the seventh AND circuit 267, respectively. The seventh AND circuit 267 performs an AND operation based on signals output from the second to fourth distance sensors 22 to 24. The seventh logical product circuit 267 outputs the logical product operation result to the logical sum circuit 259. The eighth AND circuit 268 is connected to the second, third, and fifth distance sensors 22, 23, and 25, respectively. The eighth logical product circuit 268 performs a logical product operation based on signals output from the second, third, and fifth distance sensors 22, 23, and 25. The eighth logical product circuit 268 outputs the logical product operation result to the logical sum circuit 259.

  The ninth AND circuit 269 is connected to the second, fourth, and fifth distance sensors 22, 24, and 25, respectively. The ninth AND circuit 269 performs an AND operation based on signals output from the second, fourth, and fifth distance sensors 22, 24, 25. The ninth AND circuit 269 outputs the AND operation result to the OR circuit 259. Third to fifth distance sensors 23 to 25 are connected to the tenth AND circuit 260, respectively. The tenth AND circuit 260 performs an AND operation based on signals output from the third to fifth distance sensors 23 to 25. The tenth logical product circuit 260 outputs the logical product operation result to the logical sum circuit 259.

  In the configuration example of the first determination circuit described above, three distance sensors are combined from five distance sensors, and an output signal of the combined distance sensor is input to each AND circuit. That is, in the case of 2n + 1 (n = 1, 2, 3,...) Distance sensors, n + 1 distance sensors are combined from 2n + 1 distance sensors, and output signals of n + 1 distance sensors are combined. May be input to each AND circuit.

  The logical sum circuit 259 performs a logical sum operation based on the logical product operation result signal (“0” or “1”) output from the first to tenth AND circuits 260 to 269. In this way, the first determination circuit combines n + 1 distance sensors from 2n + 1 distance sensors, inputs the output signals of the combined distance sensors to each AND circuit, and ORs the output signals of each AND circuit. It is configured to input to the circuit. As a result, even when an abnormality occurs in any of the 2n + 1 distance sensors, the first determination circuit can accurately determine the presence / absence of an object based on the majority of the output signals of the 2n + 1 distance sensors. .

  The second determination circuit 27 includes first to fifth exclusive OR circuits 271 to 275 corresponding to the first to fifth distance sensors 21 to 25. The first exclusive OR circuit 271 is connected to the OR circuit 259 of the first determination circuit 26 and the first distance sensor 21. The first exclusive OR circuit 271 performs an exclusive OR operation on the basis of signals output from the OR circuit 259 of the first determination circuit 26 and the first distance sensor 21, and outputs a signal (“0 Or “1”). The second exclusive OR circuit 272 is connected to the OR circuit 259 of the first determination circuit 26 and the second distance sensor 22. The second exclusive OR circuit 272 performs an exclusive OR operation based on signals output from the OR circuit 259 of the first determination circuit 26 and the second distance sensor 22 and outputs the operation result.

  The third exclusive OR circuit 273 is connected to the OR circuit 259 of the first determination circuit 26 and the third distance sensor 23. The third exclusive OR circuit 273 performs an exclusive OR operation based on signals output from the OR circuit 259 of the first determination circuit 26 and the third distance sensor 23, and outputs the operation result. The fourth exclusive OR circuit 274 is connected to the OR circuit 259 of the first determination circuit 26 and the fourth distance sensor 24. The fourth exclusive OR circuit 274 performs an exclusive OR operation based on signals output from the OR circuit 259 of the first determination circuit 26 and the fourth distance sensor 24, and outputs the operation result.

  The fifth exclusive OR circuit 275 is connected to the OR circuit 259 of the first determination circuit 26 and the fifth distance sensor 25. The fifth exclusive OR circuit 275 performs an exclusive OR operation based on signals output from the OR circuit 259 of the first determination circuit 26 and the fifth distance sensor 25, and outputs the operation result. The second determination circuit 27 can individually determine abnormality of the first to fifth distance sensors 21 to 25 based on the output signals of the first to fifth exclusive logic circuits 271 to 275. As described above, the second determination circuit includes 2n + 1 exclusive logic circuits corresponding to 2n + 1 distance sensors. Each exclusive OR circuit performs an exclusive OR operation based on the output signal of the corresponding distance sensor and the output signal of the OR circuit of the first determination circuit, and determines the abnormality of the corresponding distance sensor.

  Note that the present invention is not limited to the above-described embodiment, and can be changed as appropriate without departing from the spirit of the present invention.

  In the above-described embodiments, the present invention has been described as a hardware configuration, but the present invention is not limited to this. The present invention can be realized, for example, by causing the CPU (Central Processing Unit) to execute a computer program for the processing of the first and second determination circuits 4, 5, 26, and 27. )

  The program may be stored using various types of non-transitory computer readable media and supplied to a computer. Non-transitory computer readable media include various types of tangible storage media. Examples of non-transitory computer-readable media include magnetic recording media (for example, flexible disks, magnetic tapes, hard disk drives), magneto-optical recording media (for example, magneto-optical disks), CD-ROMs (Read Only Memory), CD-Rs, CD-R / W and semiconductor memory (for example, mask ROM, PROM (Programmable ROM), EPROM (Erasable PROM), flash ROM, RAM (random access memory)) are included. The program may also be supplied to the computer by various types of transitory computer readable media. Examples of transitory computer readable media include electrical signals, optical signals, and electromagnetic waves. The temporary computer-readable medium can supply the program to the computer via a wired communication path such as an electric wire and an optical fiber, or a wireless communication path.

  The present invention can be used, for example, for an autonomous mobile body that detects an object and autonomously moves while avoiding the detected object.

DESCRIPTION OF SYMBOLS 1 1st distance sensor 2 2nd distance sensor 3 3rd distance sensor 4 1st determination circuit 5 2nd determination circuit 6 Control apparatus 7 Warning apparatus 10 Object detection apparatus 11 Autonomous mobile body

Claims (1)

Driving means for moving the autonomous mobile body;
A sensor unit including at least three distance sensors that are directed to a road surface in the moving direction of the autonomous mobile body and detect a distance from an object in the same region;
An autonomous type comprising control means for controlling the driving means so as to decelerate or avoid the object when the distance to the object detected by each distance sensor of the sensor unit exceeds a threshold value A moving object,
The control means includes
When only one distance out of the distances detected by at least three distance sensors of the sensor unit exceeds the threshold value, or when only one distance does not exceed the threshold value, other than the one distance An autonomous mobile body characterized in that the driving means is controlled based on a determination as to whether another distance exceeds the threshold.

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