JP2010211512A - Autonomous moving device - Google Patents

Abstract

Provided is an autonomous mobile device capable of following a target while appropriately avoiding obstacles around the main body even if the main body has a traveling direction as a longitudinal direction.
An obstacle detects a moving direction of a main body in a direction of a target based on relative position information of the target captured by a laser range finder and information on surrounding obstacles detected by an obstacle sensor. If the obstacle is not detected, the direction of the target is determined. If the obstacle is detected, the direction of the space closest to the target is determined from the space in which the obstacle is not detected in the space radially extending around the main body. When turning is required to turn the main body in the determined traveling direction, the traveling direction is corrected to the straight traveling direction when there is an obstacle in the turning region.
[Selection] Figure 4

Description

  The present invention relates to an autonomous mobile device that autonomously moves following a moving target.

  For example, Patent Document 1 discloses a technology in which a moving target is a user and an autonomous mobile device on which a load is placed follows the user. When such an autonomous mobile device detects an obstacle around the device body, the device moves the device body in a predetermined direction to avoid the obstacle.

  In this type of conventional autonomous mobile device, in order to facilitate a turning operation to avoid an obstacle, the shape of the device main body is approximately equal in length in the traveling direction and in the direction orthogonal to the traveling direction. The shape, for example, a substantially perfect circle or a substantially square was used. However, in consideration of the load capacity, the body shape of the autonomous mobile device is preferably a rectangle whose longitudinal direction is the traveling direction, or a shape similar thereto. However, if the main body has a longitudinal direction as the traveling direction, there may be an obstacle in the swivel area of the main body during the swiveling operation, which may make the swivel impossible. Not considered.

  The present invention has been made based on such circumstances, and the purpose of the present invention is to follow the target by appropriately avoiding obstacles around the main body, even if the main body has the traveling direction as the longitudinal direction. It is intended to provide an autonomous mobile device that can be used.

  The present invention relates to an autonomous mobile device that autonomously moves following a moving target, a body having a longitudinal direction as a traveling direction, a capturing means for capturing the target, and an obstacle for detecting obstacles around the body. Based on the object detection means, the relative position information of the target object captured by the capturing means with respect to the surrounding obstacle information detected by the obstacle detection means, the traveling direction of the main body is changed to the direction of the target object. If the object is not detected, the direction of the target is determined. If the obstacle is detected, the direction in which the obstacle is not detected in the space radially extending around the main body is determined in the direction of the space closest to the target. A turning correction means for correcting the traveling direction to a straight traveling direction when there is an obstacle in the turning area when turning is required to direct the main body in the traveling direction determined by the determining means; Is obtained by a running control means for running direction.

  According to the present invention in which such means is taken, an autonomous mobile device that can follow an object by appropriately avoiding obstacles around the main body can be provided even if the main body has a traveling direction as a longitudinal direction.

The perspective view of the autonomous mobile device in the 1st Embodiment of the present invention. The top view which looked at the autonomous mobile device from the bottom side. The block diagram which shows the principal part structure of the autonomous mobile device. The flowchart which shows the principal part of the process sequence which the central control part of the autonomous mobile device performs. The flowchart which shows the process sequence between arrow [1]-[2] in FIG. In FIG. 4, the flowchart which shows the process sequence after arrow [3]. The figure which shows an example of the omnidirectional obstacle map used by action | operation description of the same embodiment. The schematic diagram which shows an example of the positional relationship of a main body, a target object, and an obstruction. The schematic diagram which shows the other example of the positional relationship of a main body, a target object, and an obstruction. The schematic diagram which shows the other example of the positional relationship of a main body, a target object, and an obstruction. The schematic diagram which shows the other example of the positional relationship of a main body, a target object, and an obstruction. The top view which looked at the autonomous mobile device in the 2nd Embodiment of this invention from the bottom face side. The top view which looked at the autonomous mobile device in the 3rd Embodiment of this invention from the bottom face side. The top view which looked at the autonomous mobile device in the 4th Embodiment of this invention from the bottom face side. The top view which looked at the autonomous mobile apparatus in the 5th Embodiment of this invention from the side surface side.

The best mode for carrying out the present invention will be described below with reference to the drawings.
FIG. 1 is a perspective view showing an external appearance of the autonomous mobile device 1 in the present embodiment, and FIG. 2 is a plan view of the autonomous mobile device 1 as seen from the bottom side.

  As shown in FIGS. 1 and 2, the autonomous mobile device 1 has a main body 10 in a rectangular box shape, one end surface side in the longitudinal direction of the main body 10 is a first curved surface portion 11, and the other end surface side is a first one. Two curved surface portions 12 are provided. Then, ultrasonic sensors 13a, 13b, 13c, 13d, 13e, 13f, 13g. Which are active distance sensors as obstacle sensors are respectively provided on the left and right side surface portions 10a, 10b and the first curved surface portion 11 of the main body 10. 13h and 13i are provided at predetermined intervals. The ultrasonic sensors 13a to 13i detect the presence or absence of an obstacle in the surroundings and the distance to the obstacle by transmitting and receiving ultrasonic signals.

  The autonomous mobile device 1 follows a user, for example, following a user by loading a load, and forms a recess 14 on the top of the main body 10 for loading the load, as shown in FIG.

  As shown in FIG. 2, the autonomous mobile device 1 includes a pair of drive wheels 15 a and 15 b on the left and right sides of the one end face side of the bottom surface portion 10 c of the main body 10, and a pair of auxiliary wheels (casters) on the left and right sides of the other end face side. 16a and 16b are attached symmetrically. By rotation of the drive wheels 15a and 15b, the main body 10 can move forward in the longitudinal direction of the main body 10 to the first curved surface portion 11 side, or retreat to the second curved surface portion 12 side. That is, the drive wheels 15a and 15b function as front wheels, and the auxiliary wheels 16a and 16b function as rear wheels. The left and right drive wheels 15a and 15b are independently controlled, and the main body 10 can be turned on the spot clockwise or counterclockwise depending on the difference in the number of rotations. The rotation center is an intermediate point O on the axle connecting the left and right drive wheels 15a and 15b.

  As shown in FIG. 2, when the intermediate point between the pair of drive wheels (front wheels) 15a and 15b is O and the width of the main body in the short direction perpendicular to the longitudinal direction passing through the intermediate point O is d, The first curved surface portion 11 that is the front surface of the main body 10 has a semicircular shape with the intermediate point O as the center and a radius of d / 2 (= r). When the length from the intermediate point O to the rear surface of the main body is a (> d / 2), the second curved surface portion 12 that is the rear surface of the main body 10 is an arc whose center is the intermediate point O and whose radius is a. Shape.

  As described above, the intermediate point O on the axle connecting the drive wheels 15a and 15b is set as the center of rotation, and the front end surface and the rear end surface are the first curved surface portion 11 and the second curved surface portion 12, thereby making the main body 10 Can make small turns even in a small space. Further, a useless space for the main body shape is omitted for turning, and both turning performance and a loading area can be efficiently secured.

  Each ultrasonic sensor 13a, 13b, 13c, 13d, 13e, 13f, 13g. Among 13h and 13i, sensors 13c, 13d, 13e, 13f, and 13g are provided in front of the axles of the drive wheels 15a and 15b. In particular, the sensors 13c and 13g are provided on the side of the first curved surface portion 11 in the vicinity of the drive wheels 15a and 15b. These sensors 13 c, 13 d, 13 e, and 13 f point the obstacle detection area forward from the side of the main body 10. The remaining ultrasonic sensors 13a, 13b, 13h, 13i are provided behind the axles of the drive wheels 15a, 15b. These sensors 13 a, 13 b, 13 h, and 13 i have an obstacle detection area directed to the side of the main body 10.

  The control circuit configuration of the autonomous mobile device 1 is shown in the block diagram of FIG. The autonomous mobile device 1 includes a central control unit 21, an ultrasonic sensor control unit 22, a communication interface (I / F) 23, a laser range finder (LRF) 24, a pair of motors 25a and 25b, and a pair of encoders 26a and 26b. 10 is installed.

  The central control unit 21 is composed of, for example, a microcomputer, and electrically connects the ultrasonic sensor control unit 22, the communication interface 23, the laser range finder 24, the pair of motors 25a and 25b, and the pair of encoders 26a and 26b.

  The ultrasonic sensor control unit 22 controls each of the ultrasonic sensors 13 a to 13 i connected via the signal line 27. That is, the ultrasonic sensor control unit 22 outputs an operation start trigger signal to each of the ultrasonic sensors 13a to 13i at a predetermined timing. Each of the ultrasonic sensors 13a to 13i that has received this trigger signal transmits an ultrasonic signal (a signal composed of a predetermined number of ultrasonic pulses). When there is an obstacle in the traveling direction of the ultrasonic signal, the ultrasonic signal is reflected by the obstacle, so that each of the ultrasonic sensors 13a to 13i receives the reflected wave. And if the reflected wave more than a predetermined level is received, each ultrasonic sensor 13a-13i will measure the time difference from the time which transmitted the ultrasonic signal to the time which received the reflected wave. This time difference is the time of flight of the ultrasonic signal. Each ultrasonic sensor 13a-13i calculates the distance to an obstacle from the flight time and sound speed of this ultrasonic signal. The calculated distance data is collected by the ultrasonic sensor control unit 22. The ultrasonic sensor control unit 22 transmits distance data to the obstacle collected from the ultrasonic sensors 13 a to 13 i to the central control unit 21. Here, the ultrasonic sensor control unit 22 and the ultrasonic sensors 13 a to 13 i function as an obstacle detection unit that detects an obstacle around the main body 10.

  The communication interface 23 manages data communication between the central control unit 21 and other computer devices connected to the main body 10. The communication interface 23 may be a wired interface that governs data communication using wired communication, or may be a wireless interface that governs data communication utilizing wireless communication.

  The laser range finder 24 recognizes the shape of the target that the main body 10 follows by laser scanning, and transmits the shape recognition signal to the central control unit 21. The central control unit 21 has a function as a capturing unit that captures a target based on a shape recognition signal from the laser range finder 24. Further, the central control unit 21 determines the traveling direction S of the main body 10 based on the relative position information of the target object captured by the capturing means with respect to the main body 10 and information on surrounding obstacles detected by the obstacle detecting means. If no obstacle is detected in the direction of the target, the direction of the target is determined. If an obstacle is detected, the target is out of the spaces in which no obstacle is detected in a space radially extending around the main body 10. When a turn is required to direct the main body 10 in the travel direction S determined by the determination means and the travel direction S determined by the determination means, and when there is an obstacle in the turn area, the travel direction S is set to the straight travel direction. It has a function as a turning correction means for correcting to. Further, when an obstacle is detected in the traveling direction S of the main body 10, the central control unit 21 corrects the traveling direction S of the main body 10 in a direction in which the distance from the obstacle to the main body 10 is more than a certain distance. Means, if an obstacle is not detected in the traveling direction S corrected by the direction correcting unit, a redetermining unit that determines the corrected traveling direction S as the traveling direction S of the main body 10, and after correction by the direction correcting unit When an obstacle is detected in the traveling direction S, it also has a function as a stopping means for stopping the traveling of the main body 10. These determination means, turning correction means, direction correction means, redetermination means, and stop means will be specifically described in the description of the action described later.

  The pair of motors 25a and 25b respectively apply power to the drive wheels 15a and 15b according to a command from the central control unit 21, and rotate the drive wheels 15a and 15b independently. The pair of encoders 26 a, 26 b detect the rotation of the drive wheels 15 a, 15 b and provide detection data to the central control unit 21. The central control unit 21 estimates the self-position of the main body 10 by calculation using the detection data from the encoders 26a and 26b. And the relative position information with respect to the main body 10 of the target object captured by the capturing means is calculated, and the pair of motors 25a, 25b is set in accordance with the traveling direction S of the main body 10 determined from the relative position information and information on surrounding obstacles. A drive command is given to the main body 10 to travel in the traveling direction S.

  4 to 6 are flowcharts showing a processing procedure of one cycle in the central control unit 21. Next, the operation of the autonomous mobile device 1 in this embodiment will be described with reference to this flowchart.

  The central control unit 21 firstly, as ST (step) 1, distance data to the obstacle captured from each of the ultrasonic sensors 13 a to 13 i via the ultrasonic sensor control unit 22 and a shape recognition signal from the laser range finder 24. Based on the above, an omnidirectional obstacle map is created in a range that can be detected by each of the ultrasonic sensors 13a to 13i with the main body 10 as the center. In ST2, the target 30 is captured by the shape recognition signal of the target 30 captured from the laser range finder 24. Note that either of the processing procedures of ST1 and ST2 may be first.

  In this way, if the omnidirectional obstacle map is created and the target 30 is captured, the central control unit 21 determines whether the target 30 exists in a space in which the main body 10 can travel as ST3. To do.

  This determination process will be specifically described with reference to the schematic diagram of FIG. FIG. 7 is an example of an omnidirectional obstacle map. In the figure, reference numeral 10 denotes a main body, reference numeral 30 denotes a target that the main body 10 follows, and reference numeral 40 denotes a plurality of obstacles existing around the main body 10. In addition, an axis connecting the pair of drive wheels 15a and 15b of the main body 10 is defined as an X axis, and an axis orthogonal to the X axis passing through the rotation center O that is an intermediate point between the pair of drive wheels 15a and 15b is defined as a Y axis.

  The central control unit 21 divides the space radially extending from the rotation center O of the main body into spaces A2, A4, A6 where the obstacle 40 exists and spaces A1, A3, A5 where the obstacle 40 does not exist. The central control unit 21 determines whether the space in which the target 30 is captured is a space where the obstacle 40 exists or a space where the obstacle 40 does not exist. If it is a space where the obstacle 40 exists, it is determined that the target 30 does not exist in the space in which the main body 10 can travel (NO in ST3). If it is a space where no obstacle 40 exists, it is determined that the target 30 exists in a space in which the main body 10 can travel (YES in ST3).

  In the example of FIG. 7, the target 30 is captured in a space A <b> 1 where no obstacle 40 exists. Therefore, the central control unit 21 determines that the target 30 exists in a space in which the main body 10 can travel. In this case, the central control unit 21 determines whether or not the spread angle θ1 of the space A1 in which the target 30 is present is equal to or larger than a predetermined threshold angle θ set in ST4. The expansion angle θ1 of the space A1 is an angle of an intersection that connects one boundary line P1-O and the other boundary line P2-O of the space A1 where the obstacle 40 does not exist. The central control unit 21 calculates the spread angle θ1 and determines whether or not it is greater than or equal to the threshold angle θ.

  When the spread angle θ1 of the space A1 in which the target 30 exists is less than the threshold angle θ (NO in ST4), the central control unit 21 sets the traveling direction S of the main body 10 as the center of the space A1 as ST5. Determine the direction. Thereafter, the central control unit 21 proceeds to the process of ST10.

  On the other hand, when the spread angle θ1 of the space A1 in which the target 30 exists is equal to or larger than the threshold angle θ (YES in ST4), the central control unit 21 is closer to the center C of the target 30 as ST6. The spatial boundary line P1-O or P2-O is selected. Then, the angle θ2 at the intersection of the line C-O connecting the center C of the target 30 and the rotation center O of the main body 10 and the selected one of the space boundary lines P1-O or P2-O is calculated.

At ST7, the central control unit 21 determines whether or not the angle θ2 is equal to or greater than ½ of the threshold angle θ.
This determination process will be specifically described with reference to the schematic diagram of FIG. FIG. 8 shows the positional relationship between the main body 10, the target 30 that the main body 10 follows, and the two obstacles 40 a and 40 b located in the vicinity of the target 30. In this example, the space A7 in which the target 30 is captured is a space where the obstacle 40 does not exist, and the spread angle θ1 of the space A7 matches the threshold angle θ. Further, the target 30 is closer to one space boundary line P7-O than the center line QO of the space A7. Accordingly, the spatial boundary line P7-O is selected as the spatial boundary line closer to the center C of the target 30. The angle θ2 at the intersection of the line C-O connecting the center C of the target 30 and the rotation center O of the main body 10 and the space boundary line P7-O is less than ½ of the threshold angle θ. Determined.

  When it is determined that the angle θ2 is less than ½ of the threshold angle θ (NO in ST7), the central control unit 21 selects one space boundary line P7− that selects the traveling direction S of the main body 10 as ST8. It is determined in a direction away from O by ½ of the threshold angle θ. That is, in the example of FIG. 8, since it is assumed that the expansion angle θ1 of the space A7 matches the threshold angle θ, the traveling direction S is determined in the direction of the center line Q-O of the space A7. Thereafter, the process proceeds to ST10.

  On the other hand, when it is determined that the angle θ2 is equal to or greater than ½ of the threshold angle θ (YES in ST7), the central control unit 21 determines the traveling direction S of the main body 10 as the target in ST9. Determine in the direction of the center C. An example in which the angle θ2 is ½ or more of the threshold angle θ is shown in FIG. 7. In this case, the traveling direction S is determined on a line connecting the center C of the target 30 and the rotation center O of the main body 10. . Thereafter, the process proceeds to ST10.

  On the other hand, when the target 30 does not exist in the space in which the main body 10 can travel (NO in ST3), the process proceeds to FIG. That is, the central control unit 21 selects a space closest to the capture position of the target object 30 in the space where the obstacle 40 does not exist as ST21. Then, in ST22, it is determined whether or not the space expansion angle θ1 is greater than or equal to the threshold angle θ. When the space expansion angle θ1 is less than the threshold angle θ (NO in ST22), the central control unit 21 determines the traveling direction S of the main body 10 as the direction of the center line of this space as ST23. Thereafter, the process proceeds to ST10.

  On the other hand, when the spread angle θ1 of the space is equal to or larger than the threshold angle θ (YES in ST22), the central control unit 21 sets the traveling direction S of the main body 10 as the target of the boundary line of the space as ST24. The direction is determined to be shifted by θ / 2 from the space boundary line on the object 30 side. Thereafter, the process proceeds to ST10 in FIG.

  Here, the central control unit 21 constitutes the determination means by the processes of ST1 to ST9 and ST21 to ST24.

  When the traveling direction S of the main body 10 is determined in this way, the central control unit 21 next determines whether or not a turning operation is necessary to direct the main body 10 in the traveling direction S as ST10. For example, it is determined that the turning motion is necessary in the example of FIG. 7, and it is determined that the turning motion is unnecessary in the example of FIG. If it is determined that the turning motion is unnecessary (NO in ST10), the process proceeds to ST31 in FIG.

On the other hand, when it is determined that the turning operation is necessary (YES in ST10), the central control unit 21 determines whether or not the main body 10 can be turned as ST11.
This determination process will be specifically described with reference to FIG. The positional relationship of the main body 10, the target 30 which this main body 10 follows, and the obstruction 40c located in the vicinity of the main body 10 is shown. In the case of this example, the space where the target 30 exists is a space where no obstacle exists, and the spread angle θ1 of this space is equal to or greater than the threshold angle θ, and is the space closer to the center c of the target 30. Since the angle θ2 to the boundary line is also ½ or more of the threshold angle θ, the central control unit 21 determines the traveling direction S of the main body 10 between the rotation center O of the main body 10 and the target 30 by the determining means. It is determined on the line connecting the center C. In order to orient the main body 10 in the traveling direction S, it is necessary to turn the main body 10 in the clockwise direction.

  For the X axis connecting the pair of drive wheels 15a and 15b of the main body 10, the central control unit 21 sets the right side in FIG. 9 from the rotation center O as a positive axis and the left side as a negative axis. Further, regarding the Y axis passing through the rotation center O and orthogonal to the X axis, the upper side in FIG. 9 from the X axis is a positive axis and the lower side is a negative axis. When the central control unit 21 needs to turn the main body 10 in the clockwise direction, the obstacle is in the region where both the X axis and the Y axis are positive or the region where both the X axis and the Y axis are negative. It is determined whether or not 40c is detected. Also, if it is necessary to turn the main body 10 counterclockwise, an obstacle occurs when the X axis is positive and the Y axis is negative, or when the X axis is negative and the Y axis is positive. It is determined whether or not the object 40c is detected. When the obstacle 40c is not detected, the central control unit 21 determines that turning is possible.

  When the obstacle 40c is detected, it is determined whether or not the interval W from the main body 10 to the obstacle 40c is equal to or greater than a preset safety interval. In FIG. 2, the safety interval is a value obtained by adding the variable α to a value obtained by subtracting the length d / 2 from the length a. When the unit of length is cm, the variable α is an arbitrary value within a range of 1 cm to 30 cm, for example.

  When the interval W from the main body 10 to the obstacle 40 is equal to or greater than the safe interval, the central control unit 21 determines that the turn is possible. On the other hand, when the interval W from the main body 10 to the obstacle 40 is less than the safety interval, the central control unit 21 determines that turning is impossible. In the example of FIG. 9, the obstacle 40 c is detected in a region where both the X axis and the Y axis are negative with respect to the clockwise rotation of the main body 10, and the interval W is less than the safety interval. The control unit 21 determines that turning is impossible. In FIG. 9, the position of the main body 10 when the main body 10 is turned in the traveling direction S is indicated by a broken line. As shown in the drawing, when the main body 10 is turned in the traveling direction S, the left rear of the main body 10 collides with the obstacle 40c, so that the main body 10 cannot be turned.

  When it is determined that turning is not possible (NO in ST11), the central control unit 21 corrects the turning angle in the traveling direction to 0 degrees as ST12. That is, as shown in FIG. 9, when there is an obstacle 40 in the turning area, the central control unit 21 corrects the traveling direction S to the straight traveling direction Sy (turning correction means). If it is determined that the vehicle can turn, the traveling direction is not corrected. Thereafter, the process proceeds to ST31 in FIG.

Thus, if the traveling direction S of the main body 10 is corrected as necessary, the central control unit 21 determines whether there is an obstacle 40 in the vicinity of the traveling direction S as ST31.
This determination means will be specifically described with reference to the schematic diagram of FIG. FIG. 10 shows the positional relationship between the main body 10, the target 30 that the main body 10 follows, the obstacle 40 c located in the vicinity of the main body 10, and the obstacle 40 d located in the traveling direction of the main body 10. . The positional relationship between the main body 10 and the obstacle 40c located in the vicinity thereof is the same as in FIG. Therefore, the traveling direction of the main body 10 is corrected to the straight traveling direction Sy by the turning correction means.

  The central control unit 10 calculates the minimum distance e between the main body 10 and the obstacle 40d when traveling in the determined traveling direction Sy from the vehicle width d of the main body 10 and the map position data of the obstacle 40d. Then, it is determined whether or not the minimum interval e is smaller than a preset threshold interval f. When the minimum interval e is smaller than the threshold interval f, it is determined that there is an obstacle near the traveling direction. When the minimum interval e is equal to or greater than the threshold interval f, it is determined that there is no obstacle near the traveling direction. The threshold interval f is an arbitrary value, and sets a minimum value of a safe interval that is estimated not to be affected by the obstacle 40d when the main body 10 actually passes near the obstacle 40d.

  When it is determined that there is no obstacle in the vicinity of the traveling direction (NO in ST31), the central control unit 10 issues a drive command to each of the pair of motors 25a and 25b to advance the main body 10 in the traveling direction S or Sy as ST32. The main body 10 is caused to travel in the traveling direction S (travel control means).

  On the other hand, in the example of FIG. 10, since the minimum interval e is smaller than the threshold interval f, it is determined that there is an obstacle in the vicinity of the traveling direction. In this case (YES in ST31), the central control unit 21 corrects the traveling direction of the main body 10 so that the main body 10 travels in a direction away from the obstacle 40d by a fixed distance f in ST33 (direction correcting means). In the example of FIG. 10, the traveling direction is corrected to a direction S1 that is rotated clockwise by an angle θ3 from the straight traveling direction Sy of the main body 10.

  At this time, the central control unit 10 determines whether or not the traveling direction can be corrected in ST34. If it is determined by the same determination procedure as in ST11 that the main body 10 will collide with the obstacle 40c when turning to correct the traveling direction, it is determined that correction is not possible.

  If the traveling direction can be corrected (NO in ST34), the central control unit 21 determines again whether or not there is an obstacle 40 in the vicinity of the corrected traveling direction S1 in ST35. As a result, when there is no obstacle 40 (NO in ST35), the central control unit 21 determines the corrected traveling direction S as the traveling direction of the main body 10 (redetermining means). Then, in ST32, in order to advance the main body 10 in the traveling direction S1, a drive command is given to each of the motors 25a and 25b to cause the main body 10 to travel in the traveling direction S (travel control means).

  On the other hand, as shown in FIG. 11, when the main body 10 travels in the traveling direction Sy, the minimum gap g between another obstacle 40e located on the opposite side of the obstacle 40d and the right side surface portion of the main body 10 is When it is smaller than the threshold interval f, it is determined that there is an obstacle in the vicinity of the traveling direction even as a result of the review. In this case (YES in ST35), the central control unit 21 stops the driving of the motors 25a and 25b to stop the main body 10 (stopping means).

  When the central control unit 21 repeats the processing procedures shown in the flowcharts of FIGS. 4 to 6, the main body 10 can appropriately follow the target 30 while avoiding the surrounding obstacles 40 appropriately.

  In addition, since a plurality of ultrasonic sensors 13a, 13b, 13h, and 13i are arranged on the left and right side surfaces of the main body 10 along the longitudinal direction, it is easy to check whether there is an obstacle in the turning area of the main body 10. Can be found. As for the arrangement of these sensors, it is more preferable to provide at least one set in the vicinity of the rear end of the main body 10 so that it can be easily found whether there is an obstacle in the negative region of the Y axis in FIG.

  Further, in the above-described embodiment, a configuration is adopted in which the turning center is set on the axle X of each driving front wheel 15a, 15b, and the sensors 13c, 13g are provided in the vicinity of the axle X so as to face sideways. Therefore, when it is determined whether or not turning is possible in ST11, the X axis shown in FIG. Thereby, for example, when it is determined whether or not a turning operation is necessary as compared with the case where the X axis is set at the center of the main body 10, it is possible to determine whether or not the turning is required at an earlier stage. It becomes.

  In addition, as shown in FIG. 2, by disposing the sensors 13c and 13g toward the front rather than the side, obstacles ahead that frequently become obstacles in traveling can be found quickly and accurately. It becomes possible.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage.

  For example, the shape and structure of the main body 10 in the autonomous mobile device 1 are not limited to those of the above embodiment.

  FIG. 12 is a plan view of the main body 10 of the autonomous mobile device 1 according to the second embodiment as viewed from the bottom surface side, and the same reference numerals are given to portions common to FIG. 2 of the first embodiment. . In the second embodiment, the first curved surface portion 11 having a semicircular shape is cut in the longitudinal direction in front of the pair of drive wheels 15a and 15b, and an ultrasonic sensor 13d is formed on a plane which is the cut surface. , 13e, 13f are arranged. Thus, the distance from the rotation center O, which is the midpoint on the axle of the pair of drive wheels 15a and 15b, to the front surface of the main body may be smaller than d / 2 (= r). In this embodiment, the number of auxiliary wheels 16 that are rear wheels is one. Thus, the number of auxiliary wheels may be one, or three or more.

  FIG. 13 is a plan view of the main body 10 of the autonomous mobile device 1 in the third embodiment as viewed from the bottom surface side, and FIG. 14 is a plan view of the main body 10 of the autonomous mobile device 1 in the fourth embodiment as viewed from the bottom surface side. FIG. In the third embodiment, a pair of front wheels 17a and 17b attached symmetrically is fixed, and one rear wheel 18 attached to the center of the bottom face of the main body 10c in the longitudinal direction is used as a drive wheel. In the fourth embodiment, the front wheels 17 a and 17 b are differential drive wheels and are rotated by the rear wheels 18. In any of the embodiments, the same operational effects as those of the first embodiment can be obtained.

  FIG. 15: is the top view which looked at the main body 10 of the autonomous mobile device 1 in 5th Embodiment from the one side surface side. In the fifth embodiment, ultrasonic sensors 13a, 13b, 13c, 13d, 13e, 13f, 13g, 13h, and 13i provided on the left and right side surfaces 10a and 10b and the first curved surface portion 11 of the main body 10 are respectively provided. A plurality are arranged in rows in the vertical direction. That is, a plurality of ultrasonic sensors 13 a, 13 b, 13 h, and 13 i arranged on the left and right side surfaces of the main body 10 along the longitudinal direction, and a plurality of ultrasonic sensors arranged on the front surface of the main body 10 along the short direction. The ultrasonic sensors 13c, 13d, 13e, 13f, and 13g are arranged over a plurality of upper and lower rows. Therefore, even if there is an obstacle whose bottom is recessed or an obstacle protruding near the center, it can be reliably detected and avoided.

  In addition, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, the constituent elements over different embodiments may be combined.

  DESCRIPTION OF SYMBOLS 1 ... Autonomous moving apparatus, 10 ... Main body, 11 ... 1st curved surface part, 12 ... 2nd curved surface part, 13a-13i ... Ultrasonic sensor, 14 ... Recessed part, 15a, 15b ... Drive wheel, 16a, 16b auxiliary wheel 21 ... Central control unit, 22 ... Ultrasonic sensor control unit, 23 ... Communication interface, 24 ... Laser range finder, 25a, 25b ... Motor, 26a, 26b ... Encoder.

JP 2006-134221 A

Claims (11)

In an autonomous mobile device that moves autonomously following a moving target,
A main body whose longitudinal direction is the traveling direction;
Capturing means for capturing the target;
Obstacle detection means for detecting obstacles around the body;
Based on the relative position information of the target object captured by the capturing means with respect to the main body and the information of surrounding obstacles detected by the obstacle detecting means, the traveling direction of the main body is set in the direction of the target object. If no obstacle is detected, the direction of the target is determined. If an obstacle is detected, the space that radiates around the main body has a direction that is closest to the target in the space where no obstacle is detected. A decision means to decide;
A turning correction means for correcting the traveling direction to a straight traveling direction when there is an obstacle in the turning area when turning is required to direct the main body in the traveling direction determined by the determining means;
Traveling control means for traveling the main body in the traveling direction;
An autonomous mobile device characterized by comprising: When an obstacle is detected in the advancing direction of the main body, direction correction means for correcting the advancing direction of the main body in a direction in which an interval from the obstacle to the main body opens more than a predetermined interval;
The autonomous mobile device according to claim 1, further comprising: If an obstacle is not detected in the travel direction corrected by the direction correction unit, the redetermination unit determines the travel direction after correction as the travel direction of the main body.
The autonomous mobile device according to claim 2, further comprising: Stop means for stopping travel of the main body when an obstacle is detected in the traveling direction after correction by the direction correction means,
The autonomous mobile device according to claim 3, further comprising:   The pair of left and right front wheels and at least one rear wheel are disposed along the longitudinal direction of the main body, and the center of rotation of the main body when turning is on the axle of the pair of front wheels. The autonomous mobile device according to any one of 1 to 4.   When the center between the pair of front wheels is O and the width of the main body in the short direction perpendicular to the longitudinal direction passing through the center O is d, the distance from the center O to the front surface of the main body is d / 2. 6. The autonomous mobile device according to claim 5, wherein a main body dimension is set so that a distance from the center O to the rear surface of the main body is greater than d / 2.   When the distance from the center O to the rear surface of the main body is a (> d / 2), the front surface of the main body has a semicircular shape with the center O as the center and a radius of d / 2. 7. The autonomous mobile device according to claim 6, wherein the shape of the rear surface is an arc shape having the center O as a center and a radius as a.   The autonomous movement according to any one of claims 1 to 4, wherein the obstacle detection means includes a plurality of obstacle sensors arranged on the left and right side surfaces of the main body, respectively, along the longitudinal direction. apparatus.   A pair of left and right front wheels and at least one rear wheel are disposed in the main body along the longitudinal direction, and the center of rotation of the main body when turning is on the axle of the pair of front wheels. 9. The autonomous mobile device according to claim 8, wherein at least one set of obstacle sensors is provided on a side surface.   The autonomous mobile device according to claim 9, wherein the obstacle sensors provided on the left and right side surfaces in front of the axle have an obstacle detection area directed forward from a side of the main body.   The autonomous mobile device according to claim 8, wherein the plurality of obstacle sensors arranged on the left and right side surfaces of the main body in the longitudinal direction are arranged in a plurality of vertical rows.

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