JP2023072736A - Autonomous traveling apparatus and control method - Google Patents

Abstract

To provide an autonomous traveling apparatus capable of suppressing a rise in an arithmetic load and attaining precise traveling alongside a wall.SOLUTION: An autonomous traveling apparatus that travels based on self-position estimation includes: a sensor that measures a distance and direction with respect to a surrounding wall; a wall detection unit that detects the wall on the basis of the distance and direction measured by the sensor; a self-position estimation unit that estimates a self-position of the autonomous traveling apparatus; a traveling route planning unit that plans a traveling route on the basis of the self-position and map information; and a traveling mode switching unit that switches between a self-position estimation traveling mode in which the autonomous traveling apparatus travels based on the self-position estimation performed by the self-position estimation unit and a wall side traveling mode in which the autonomous traveling apparatus travels maintaining a distance from the wall. The traveling mode switching unit switches between the self-position estimation traveling mode and the wall side traveling mode on the basis of the traveling route and the detected wall.SELECTED DRAWING: Figure 1

Description

The present invention relates to an autonomous mobile device and control method.

A general driving mode in a general environment in which the robot runs autonomously along a preset route using the position and orientation estimation unit that estimates the position and orientation of the device based on the detection results from the distance sensor, and forward movement in the direction of travel. There is known an autonomous mobile body that has two operation modes, a wall-following mode and a wall-following mode (see, for example, Patent Literature 1).

JP 2014-67223 A

When autonomous driving is performed by a robot, etc., a map based on sensor data is created in advance, where the robot is located is estimated from the sensor data, etc., and distance from the current location to the destination is calculated based on nearby obstacle information and map information. A common method is to plan a route so as not to collide with an obstacle, and to travel based on the plan.

A grid-like map called a grid map is generally used for this self-position estimation map, and this grid-like map has a value indicating whether or not there is an object detected by the sensor for each grid. ing.

Since the self-location is estimated from this map and current sensor information, etc., the resolution of this grid map greatly depends on the accuracy of self-location estimation.

In autonomous driving, there are cases in which an AGV (Automatic Guided Vehicle) or the like runs close to a wall (for example, several centimeters) for purposes such as cleaning every corner with a vacuum cleaner or the like.

Accumulation of odometry deviations due to minute wheel slippage, etc., and changes in the surrounding environment and noise cause deviations in the self-position during vehicle travel. and it is very difficult to require an accuracy of several centimeters. These errors are not a big problem in applications such as carrying things from a certain point to a destination point, but when accuracy is required such as maintaining a distance of several centimeters from the wall and traveling, this deviation may cause the wall to move. There are problems such as collisions.

This problem can be solved by increasing the map resolution as described above, but increasing the map resolution leads to an increase in the computational load for self-localization, which is necessary for some driving. However, there is a disadvantage that the calculation cost of autonomous driving itself is high in order to achieve high accuracy.

In addition to the autonomous driving described above, when high-precision driving is required, such as when driving near a wall, a method is adopted in which the distance and angle to the wall detected by the sensor are directly fed back to the driving. This is running that directly uses sensor values, and is an operation for performing locally optimal running. In other words, unlike the above-mentioned autonomous driving, it does not use information such as maps, so it can drive flexibly, such as when heading to a distant destination or taking a detour when the route is blocked. is difficult.

In addition, in Patent Document 1, modes called normal running and wall-following running are prepared, and a desired operation is performed by switching between them. These modes are switched only based on whether or not they have reached a preset mode change position. Since it only travels without colliding with obstacles, it is difficult to take flexible measures such as traveling on a detour when the route is blocked.

One aspect of the present invention is to suppress an increase in computational load by appropriately switching between a self-position estimation running mode in which the vehicle runs based on self-position estimation and a wall-along running mode in which the vehicle runs while maintaining a distance from the wall. It is an object of the present invention to provide an autonomous traveling device and a control method that realize precise traveling along a wall.

An autonomous mobile device according to an aspect of the present invention is an autonomous mobile device that travels based on self-position estimation, comprising: a sensor that measures a distance and direction to a surrounding wall; A wall detection unit that detects a wall, a self-position estimation unit that estimates the self-position of the autonomous mobile device, a travel route planning unit that plans a travel route based on the self-position and map information, and the self-position estimation. a running mode switching unit for switching between a self-position estimation running mode for running based on the self-position estimation by the unit and a wall-along running mode for running while maintaining a distance from the wall, wherein the running mode switching unit The self-position estimation running mode and the wall-along running mode are switched based on the running route and the detected wall.

A control method according to an aspect of the present invention is a control method for an autonomous mobile device that travels based on self-position estimation, in which a distance and direction to a surrounding wall are measured, and the wall is moved from the measured distance and direction. estimating a self-position of the autonomous mobile device; planning a travel route based on the self-position and map information; and based on the self-position estimation based on the travel route and the detected wall A process of switching between a self-position estimation running mode in which the vehicle runs and a wall-along running mode in which the vehicle runs while maintaining a distance from the wall is provided.

1 is an example of a configuration diagram of an autonomous mobile device according to an embodiment; FIG. FIG. 5 is a diagram showing an example of a case where it is determined that the vehicle will travel in the self-position estimation travel mode. FIG. 10 is a diagram showing an example of a case where it is determined that the vehicle will travel in the wall-aligned travel mode. It is a figure explaining collision avoidance with a wall. It is a figure for demonstrating detachment|separation operation|movement. It is a figure for demonstrating detachment|separation operation|movement. It is an example of the flowchart of the control method of the autonomous driving control part which concerns on embodiment. 6 is an example of a flow chart of a control method of the along-wall traveling control unit according to the embodiment. It is an example of the flowchart of the control method of the driving mode switching part which concerns on embodiment. FIG. 5 is a diagram showing an example of a case where it is determined that the vehicle will travel in the self-position estimation travel mode. FIG. 10 is a diagram showing an example of a case where it is determined that the vehicle will travel in the wall-aligned travel mode. FIG. 5 is a diagram showing an example of a case where it is determined that the vehicle will travel in the self-position estimation travel mode. FIG. 10 is a diagram showing an example of a case where it is determined that the vehicle will travel in the wall-aligned travel mode.

Hereinafter, embodiments will be described with reference to the drawings. In the drawings, the same or equivalent elements are denoted by the same reference numerals, and overlapping descriptions are omitted.

FIG. 1 is an example of a configuration diagram of an autonomous mobile device according to an embodiment.

The autonomous mobile device 101 has a sensor 111 , an autonomous travel control unit 121 , a wall-along travel control unit 131 , a travel mode switching unit 141 , a storage unit 151 , and a drive unit 161 .

The sensor 111 measures the position (distance and direction) of obstacles (for example, walls) around the autonomous mobile device 101 . The sensor 111 is, for example, a LiDAR (Light Detection and Ranging) sensor. The sensor 111 outputs information (sensor information) about the detected obstacles around the autonomous driving control unit 111 . The sensor information is, for example, information indicating the position of the obstacle, specifically the direction of the obstacle with respect to the sensor 111, the distance between the autonomous mobile device 101 (sensor 111) and the obstacle, and the like. The autonomous mobile device 101 is provided with, for example, a plurality of sensors 111, and can detect obstacles all around the autonomous mobile device 101 (a range of 360 degrees around the autonomous mobile device 101). In the following embodiments, a case where the position of a wall is measured as an example of the position of an obstacle will be described.

The autonomous traveling control unit 121 performs control for traveling in a self-position estimation traveling mode in which the vehicle travels based on self-position estimation. The autonomous travel control unit 121 has a self-position estimation unit 122 , a travel route planning unit 123 and a travel control unit 124 . The autonomous driving control unit 121 is implemented by, for example, a processor such as a CPU (Central Processing Unit), or a logic circuit (hardware) formed in an integrated circuit (IC (Integrated Circuit) chip) or the like.

The self-position estimation unit 122 acquires the map information 152 from the storage unit 151, acquires information (sensor information) about obstacles around the autonomous driving control unit 121 detected from the sensor 111, and stores the map information 152 and the sensor information. Based on this, the position (self-position) of the autonomous mobile device 101 is estimated.

The travel route planning unit 123 plans (calculates) a route (travel route) along which the autonomous mobile device 101 travels. For example, the travel route planning unit 123 sets a departure position and a destination position by input from the outside, etc., and plans a travel route to the destination position based on map information and the like. The travel route planning unit 123 outputs a planned travel route indicating the planned travel route to the travel mode switching unit 141 .

Travel control unit 124 generates a travel command for traveling the travel route planned by travel route planning unit 123 based on the self-position estimated by self-position estimating unit 122, and outputs the travel command to travel mode switching unit 141. . That is, the travel control unit 124 generates and outputs a travel command for traveling in the self-position estimation travel mode. The travel command includes, for example, a command for controlling the drive unit 161 to travel along the travel route.

The wall-along-travel control unit 131 detects surrounding walls based on sensor information, and feeds back the distance between the autonomous mobile device 101 and the wall and the traveling direction of the autonomous mobile device 101 and the angle with respect to the wall. Control is performed to run in wall-along running mode while maintaining a distance (for example, several centimeters). The along-wall travel control unit 131 has a wall detection unit 132 and a travel control unit 133 . The wall-along-travel control unit 131 is realized by, for example, a processor such as a CPU, or a logic circuit (hardware) formed in an integrated circuit (IC chip) or the like.

The wall detection unit 132 detects walls around the autonomous mobile device 101 based on sensor information from the sensor 111 . The wall detection unit 132 outputs wall information indicating the position of the detected wall to the running mode switching unit 141 . The wall information includes, for example, the direction in which the wall exists with respect to the autonomous mobile device 101 (sensor 111) and the distance between the autonomous mobile device 101 (sensor 111) and the wall.

The traveling control unit 133 receives sensor information from the sensor 111 and travels along the wall based on wall information (wall information) detected by the wall detection unit 132, that is, travels while maintaining a constant distance from the wall. A running command for switching is generated and output to the running mode switching unit 141 . That is, the travel control unit 133 generates and outputs a travel command for traveling in the along-the-wall travel mode. The distance between the autonomous mobile device 101 and the wall when traveling along the wall is set in advance. Also, the distance between the autonomous mobile device 101 and the wall when traveling along a wall may be given from the outside during travel. The run command includes, for example, a command for controlling the drive unit 161 to keep the distance from the wall constant and run.

The running mode switching unit 141 has a determination unit 142 and a leaving operation control unit 143 . The running mode switching unit 141 is implemented by, for example, a processor such as a CPU, or a logic circuit (hardware) formed in an integrated circuit (IC chip) or the like.

Based on the travel plan route received from the travel route planning unit 123 and the wall information received from the wall detection unit 132, the determination unit 142 switches between the self-position estimation travel mode and the wall-alongside travel mode. Specifically, for example, the determining unit 142 determines which of the self-position estimation driving mode and the wall-along driving mode is selected based on the planned driving route received from the driving route planning unit 123 and the wall information received from the wall detecting unit 132. determines whether to run in the running mode.

For example, as described below, the determination unit 142 determines, based on the distance between the planned travel route and the wall, whether to use the self-position estimation travel mode or the along-the-wall travel mode. The distance between the travel plan route and the wall can be calculated based on the wall information indicating the position of the wall.

FIG. 2A is a diagram showing an example when it is determined that the vehicle is traveling in the self-position estimation traveling mode. FIG. 2B is a diagram showing an example of a case where it is determined that the vehicle will travel in the along-the-wall traveling mode.

2A and 2B are plan views of the autonomous mobile device 101 viewed from above. An arrow in the autonomous mobile device 101 indicates the traveling direction of the autonomous mobile device 101, and the rightward direction in FIGS. 2A and 2B is the traveling direction of the autonomous mobile device 101. FIG. 2A and 2B, there is a wall W detected by the wall detection unit 132 on the right side of the autonomous mobile device 101 in the traveling direction. Also, an arrow extending from the autonomous mobile device 101 indicates a travel route (planned travel route) planned by the travel route planning unit 123 .

In FIGS. 2A and 2B, a rectangular range surrounded by dotted lines indicates a range from the autonomous mobile device 101 to the distance D along the wall W and from the wall W to the threshold th in the vertical direction of the wall.

In FIG. 2A, the travel plan route is at a position where the distance from the wall W is greater than the threshold value th.

As shown in FIG. 2A, if at least part of the travel plan route is located farther from the wall W than the threshold value th between the autonomous mobile device 101 and the distance D in the direction along the wall W, it is determined The unit 142 determines to travel in the self-position estimation travel mode.

In FIG. 2B, from the autonomous mobile device 101 to the distance D in the direction along the wall W, all of the planned travel routes are within the threshold th from the wall W. In FIG.

As shown in FIG. 2B, if at least part of the travel plan route is not located farther from the wall W than the threshold value th within the distance D from the autonomous mobile device 101 in the direction along the wall W, it is determined The unit 142 determines to run in the along-the-wall running mode. When all of the planned travel routes are within the threshold th from the wall W, the determination unit 142 determines that the vehicle travels in the along-the-wall travel mode.

In this way, when the distance between the planned travel route and the wall is within a certain distance (threshold value), it is determined that the vehicle will travel in the wall-along traveling mode. .

Returning to FIG. 1, the description continues.

When determining to travel in the self-position estimation travel mode, determination unit 142 outputs the travel command received from travel control unit 124 to drive unit 161 . As a result, the autonomous mobile device 101 runs in the self-position estimation running mode.

When determining to travel in the along-the-wall travel mode, the determination unit 142 outputs the travel command received from the travel control unit 133 to the drive unit 161 . As a result, the autonomous mobile device 101 travels in the along-the-wall traveling mode.

In this way, the determination unit 142 switches between the self-position estimation running mode and the along-the-wall running mode by outputting the running command according to the determination result of the running mode.

The leaving motion control unit 143 generates a travel command for performing a leaving motion in which the autonomous mobile device 101 travels away from the wall so as not to collide with the wall, and outputs the command to the driving unit 161 . For example, based on the wall information and the information indicating the shape of the autonomous mobile device 101, the leaving motion control unit 143 restricts the autonomous mobile device 101 from colliding with the wall from turning in the direction in which it collides with the wall. A travel command is generated to perform a detachment motion to go straight while restricting turning and to move away from the wall so as not to collide with the wall. Information indicating the shape of the autonomous mobile device 101 is stored in advance in the storage unit 151 .

If the autonomous mobile device 101 switches to the self-position estimation traveling mode while traveling along a wall, it may collide with the wall and become unable to travel due to a discrepancy between the estimated self-position and the actual autonomous mobile device 101 . In order to avoid this, the leaving motion control unit 143 realizes traveling to leave the wall without colliding with it by control based on the shape of the vehicle body and the distance and angle to the wall.

FIG. 3 is a diagram for explaining collision avoidance with a wall.

FIG. 3 is a plan view of the autonomous mobile device 101 viewed from above. Also, the autonomous mobile device 101 has a rectangular shape when viewed from above, and an arrow in the autonomous mobile device 101 indicates the traveling direction of the autonomous mobile device 101 .

Since the autonomous mobile device 101 is approaching the wall when it leaves the wall, there is a high risk of colliding with the wall when it turns. Therefore, when performing the leaving motion, the leaving motion control section 143 performs appropriate control in consideration of the shape of the vehicle body.

Specifically, the leaving motion control unit 143 calculates the distance between the position closest to the wall and the wall behind the turning center of the vehicle body, and if it is likely to collide with the wall during turning, the vehicle moves toward the collision direction. to avoid collisions by limiting the turning of the

In FIG. 3, when the autonomous mobile device 101 tries to turn counterclockwise, the right rear corner portion of the autonomous mobile device 101 indicated by the circle is the closest position to the wall W. , the distance between the right rear corner of the autonomous mobile device 101 and the wall is calculated, and if there is a risk of collision, a travel command is generated to limit left turn and go straight, thereby preventing collision with the wall. Perform a break away from the wall.

4A and 4B are diagrams for explaining the detachment operation.

4A and 4B are plan views of the autonomous mobile device 101 viewed from above. An arrow in the autonomous mobile device 101 indicates the traveling direction of the autonomous mobile device 101 . FIG. 4A shows how the autonomous mobile device 101 moves away from the wall without colliding with it. The leftmost autonomous mobile device 101 indicates the position of the first autonomous mobile device 101. The autonomous mobile device 101 moves to the position of the adjacent autonomous mobile device 101 on the right. The distance D1 indicates the distance that the vehicle can travel in the self-position estimation mode away from the wall, and the distance D2 indicates the distance required to escape from the wall.

As shown in FIG. 4A, when the autonomous mobile device 101 attempts to turn counterclockwise at the initial position, the right rear corner portion of the autonomous mobile device 101 collides with the wall W, so the autonomous mobile device 101 turns left. By restricting (reducing the turning angle) and moving forward, it prevents collision with the wall and escapes from the wall. Then, the autonomous mobile device 101 travels in the self-position estimation traveling mode when the autonomous mobile device 101 is separated from the wall by the distance D1 by the detachment operation. If the shape of the autonomous mobile device 101 when viewed from above is not circular, there is a limit to the angle at which the autonomous mobile device 101 can turn without colliding with the wall W, and the autonomous mobile device 101 moves away from the wall by a distance D1 without colliding with the wall W. requires a distance D2 in the traveling direction of the autonomous mobile device 101 at the start of the leaving operation. The distance D2 required to leave the wall is the distance from when the autonomous mobile device 101 starts running (leaving motion) to leave the wall without colliding with it and moves to a position where it can run in the self-position estimation mode. is the distance from the autonomous mobile device 101 to the wall in the traveling direction of the autonomous mobile device 101 at the start of the separation operation.

Further, the determination unit 142 determines whether or not to perform the leaving operation based on whether or not there is an obstacle within the distance D2 in the traveling direction of the autonomous mobile device 101 from the autonomous mobile device 101 while traveling in the along-the-wall traveling mode. You can judge. For example, the determining unit 142 determines that the leaving operation is to be performed when an obstacle occurs within a distance D2 in the traveling direction of the autonomous mobile device 101 from the autonomous mobile device 101 while traveling in the wall-along-running mode. At this time, if the distance D2 cannot be secured without colliding with the wall W at the start of the leaving operation due to the influence of an obstacle that suddenly occurs, the autonomous mobile device 101 travels backward along the wall (backward). After securing the distance D2 by performing, the movement to leave the wall is performed. Backward traveling along the wall can be realized by traveling while feeding back the angle of the wall in the same manner as in forward traveling.

For example, as shown in FIG. 4B, when the distance D3 from the autonomous mobile device 101 to the obstacle A in the traveling direction of the autonomous mobile device 101 is smaller than the distance D2 required to break away from the wall W, the autonomous mobile device 101 The robot travels backward along the wall (backward), and after the distance D3 from the autonomous mobile device 101 to the obstacle A becomes equal to or greater than the distance D2, it leaves the wall. Thus, at the start of the leaving operation of the autonomous mobile device 101, the distance D3 from the autonomous mobile device 101 to the obstacle A in the traveling direction of the autonomous mobile device 101 is greater than or equal to the distance D2 required to leave the wall W. .

Returning to FIG. 1, the description continues.

If the determination unit 142 determines to run in the self-position estimation running mode while running along the wall (during running in the wall-aligning running mode), the determination unit 142 transmits the running command from the detachment operation control unit 143 to the driving unit 161. After the autonomous mobile device 101 leaves the vehicle, the travel command received from the travel control unit 124 may be output to the drive unit 161 . That is, after a certain distance or more from the wall is made by the detachment operation, the mode is changed to the self-position estimation running mode. In determining whether or not the autonomous mobile device 101 is traveling along the wall, for example, when the autonomous mobile device 101 is traveling within a predetermined distance from the wall, the determination unit 142 determines that the autonomous mobile device 101 is traveling along the wall. .

The storage unit 151 is a storage device that stores programs, data, and the like used by the autonomous mobile device 101 . The storage unit 151 stores map information 152 . The storage unit 151 is, for example, a ROM (Read Only Memory), a RAM (Random Access Memory), or an SSD (Solid State Drive).

The map information 152 includes, for example, information regarding obstacles such as walls that exist in the area where the autonomous mobile device 101 travels. The map information 152 is, for example, a grid-like map called a grid map, and the presence or absence of obstacles such as walls is indicated for each grid-like area (grid).

The drive unit 161 causes the autonomous mobile device 101 to travel according to the travel command from the travel mode switching unit 141 . The drive unit 161 includes, for example, a drive motor and wheels, and causes the autonomous mobile device 101 to travel by the drive motor driving the wheels according to the travel command from the travel mode switching unit 141 .

FIG. 5 is an example of a flowchart of a control method for an autonomous driving control unit according to the embodiment.

In step S501, the self-position estimation unit 122 acquires map information from the storage unit 151, acquires sensor information from the sensor 111, and calculates the position (self-position) of the autonomous mobile device 101 based on the map information and the sensor information. to estimate

In step S502, the travel route planning unit 123 plans (calculates) a route (travel route) along which the autonomous mobile device 101 travels. For example, the travel route planning unit 123 sets the departure position and the destination position by input from the outside, etc., and plans the travel route to the destination position based on the map information. Then, the travel route planning unit 123 outputs a planned travel route indicating the planned travel route to the travel mode switching unit 141 .

In step S503, the traveling control unit 124 generates a traveling command for traveling the traveling route planned by the traveling route planning unit 123 based on the self-position estimated by the self-position estimating unit 122, and the traveling mode switching unit 141.

The autonomous driving control unit 121 repeats the processes of steps S501 to S503.

FIG. 6 is an example of a flow chart of a control method of the along-the-wall traveling control unit according to the embodiment.

In step S601, the wall detection unit 132 acquires sensor information from the sensor 111, and detects walls around the autonomous mobile device 101 based on the sensor information. The wall detection unit 132 outputs wall information indicating the position of the detected wall to the running mode switching unit 141 .

In step S602, the running control unit 133 generates a running command for running (running along the wall) while maintaining a constant distance from the wall based on the sensor information from the sensor 111, and generates a running command for running along the wall. 141.

FIG. 7 is an example of a flowchart of a control method for the driving mode switching unit according to the embodiment.

In step S701, the determination unit 142 receives a travel plan route from the travel route planning unit 123, receives a travel command from the travel control unit 124, receives wall information from the wall detection unit 132, and travels from the travel control unit 133. Receive commands. Based on the planned travel route and the wall information, the determination unit 142 determines whether the vehicle is to be used in either the self-position estimation travel mode or the along-the-wall travel mode. The details of the determination method are as described with reference to FIGS. 2A and 2B.

In step S702, if it is determined in step S701 that the vehicle will travel in the wall-along traveling mode, the control proceeds to step S703, and if it is determined that the vehicle will travel in the self-position estimation traveling mode, the control proceeds to step S704.

In step S<b>703 , the determination unit 142 outputs to the driving unit 161 the travel command for traveling along the wall received from the travel control unit 133 . As a result, the autonomous mobile device 101 travels in the along-the-wall traveling mode.

In step S704, the determination unit 142 determines whether or not the autonomous mobile device 101 is traveling along a wall. For example, the determination unit 142 determines whether the position of the autonomous mobile device 101 is within a predetermined distance from the wall based on the wall information. is determined to be running. If it is determined that the autonomous mobile device 101 is traveling along the wall, control proceeds to step S705, and if it is determined that the autonomous mobile device 101 is not traveling along the wall, control proceeds to step S706.

In step S<b>705 , the leaving motion control unit 143 generates a travel command for performing a leaving motion so that the autonomous mobile device 101 does not collide with a wall, and outputs it to the drive unit 161 .

In step S<b>706 , the determination unit 142 outputs to the drive unit 161 a travel command for traveling the travel route planned by the travel route planning unit 123 received from the travel control unit 124 . As a result, the autonomous mobile device 101 runs in the self-position estimation running mode.

The autonomous mobile device 101 may further have a display unit (for example, a liquid crystal panel, an organic EL (Electro Luminescence) panel, or the like). The running mode switching unit 132 may display the current running mode on the display during running. Specifically, for example, the running mode switching unit 132 may display on the display unit that the vehicle is in the self-position estimation running mode, the along-the-wall running mode, or the detachment operation during running. Thereby, the autonomous mobile device 101 can notify the current traveling mode to the outside. Further, the travel mode switching unit 132 may display the angle of the planned travel route with respect to the obstacle on the display unit at any time. As a result, the autonomous mobile device 101 can notify the outside of the transition to the wall-along-travel mode, the timing of the movement to leave the wall, and the like.

(Other embodiments)
Determination unit 142 determines whether to run in the self-position estimation running mode or along the wall running mode based on the following range based on the running route and the direction parallel to the wall. may

FIG. 8A is a diagram showing an example when it is determined that the vehicle is traveling in the self-position estimation traveling mode. FIG. 8B is a diagram showing an example of a case where it is determined that the vehicle will travel in the along-the-wall traveling mode.

8A and 8B are plan views of the autonomous mobile device 101 viewed from above. The arrow in the autonomous mobile device 101 indicates the traveling direction of the autonomous mobile device 101, and the rightward direction in FIGS. 8A and 8B is the traveling direction of the autonomous mobile device 101. FIG. 8A and 8B, there is a wall W detected by the wall detector 132 on the right side of the traveling direction of the autonomous mobile device 101 . A solid-line arrow extending from the autonomous mobile device 101 indicates a travel route (planned travel route) planned by the travel route planning unit 123 . A dotted arrow extending from the autonomous mobile device 101 indicates a direction parallel to the wall W. FIG.

In FIGS. 8A and 8B, the range of the triangle surrounded by the dotted line is within the distance D from the autonomous mobile device 101 in the direction parallel to the wall W, and at the angle α from the autonomous mobile device 101 to the direction parallel to the wall W. indicate the range. A triangular range surrounded by dotted lines is an example of a range based on the direction parallel to the wall.

In FIG. 8A, since there is an obstacle A in front of the autonomous mobile device 101, the travel plan route is curved, and is positioned outside the range of the angle α centered in the direction parallel to the wall W from the middle of the travel plan route. be.

As shown in FIG. 8A , at least part of the planned travel route extends from the autonomous mobile device 101 to the direction parallel to the wall W at an angle α from the autonomous mobile device 101 to the distance D in the direction parallel to the wall W, as shown in FIG. When it is outside the range of , the determination unit 142 may determine to travel in the self-position estimation travel mode.

In FIG. 8B, from the autonomous mobile device 101 to the distance D in the direction along the wall W, all of the planned travel routes are within the range of the angle α centered on the direction parallel to the wall W from the autonomous mobile device 101. It is in.

As shown in FIG. 8B , at least part of the planned travel route extends from the autonomous mobile device 101 to the direction parallel to the wall W at an angle α from the autonomous mobile device 101 to the distance D in the direction parallel to the wall W, as shown in FIG. 8B . , the determination unit 142 may determine to run in the along-the-wall running mode. That is, all of the travel planned routes from the autonomous mobile device 101 to the distance D in the direction parallel to the wall W and from the autonomous mobile device 101 to the distance D in the direction along the wall W are from the autonomous mobile device 101 to the wall W. If the vehicle is inside the range of the angle α with the parallel direction as the center, the determination unit 142 may determine to run in the along-the-wall running mode.

The determination methods described with reference to FIGS. 8A and 8B may be used alone, or may be used in combination with other determination methods.

In addition, the judgment unit 142 may decide whether to travel in the self-position estimation traveling mode or along the wall traveling mode based on the angle with respect to the wall of the traveling route as follows. .

FIG. 9A is a diagram showing an example when it is determined that the vehicle is traveling in the self-position estimation traveling mode. FIG. 9B is a diagram showing an example of a case where it is determined that the vehicle will travel in the wall-along traveling mode.

9A and 9B are plan views of the autonomous mobile device 101 viewed from above. An arrow in the autonomous mobile device 101 indicates the traveling direction of the autonomous mobile device 101, and the rightward direction in FIGS. 9A and 9B is the traveling direction of the autonomous mobile device 101. FIG. 9A and 9B, there is a wall W detected by the wall detector 132 on the right side of the traveling direction of the autonomous mobile device 101 . Also, an arrow extending from the autonomous mobile device 101 indicates a travel route (planned travel route) planned by the travel route planning unit 123 .

The travel plan route is given in detail by a plurality of points on the travel plan route, indicated by points a to f in order of proximity from the autonomous mobile device 101 in FIGS. 9A and 9B. As shown in FIGS. 9A and 9B, the travel plan route includes a section 101a connecting the autonomous mobile device 101 and the point a, a section ab connecting the point a and the point b, a section bc connecting the point b and the point c, and a section bc connecting the point b and the point c. It connects the travel section cd connecting point c and point d, the section de connecting point d and point e, and the section ef connecting point d and point f.

In FIG. 9A, since there is an obstacle A in front of the autonomous mobile device 101, the planned travel route is a U-turn route. Further, the angle of the section cd with respect to the wall W in the travel plan route is θ. Also, the angle θ is greater than a predetermined threshold. Also, the section 101a, the section ab, and the section bc are substantially parallel to the wall W, and the angles of the section 101a, the section ab, and the section bc with respect to the wall W are equal to or less than the threshold.

As shown in FIG. 9A , at least n sections (section 101a, section ab, section bc, section cd) (section 101a, section ab, section bc, section cd) in order from the closest to the autonomous mobile device 101 on the travel plan route (for example, n=4) When the angle with respect to the wall W of some sections is more than a threshold, the determination part 142 may determine with driving|running|working in self-position estimation driving mode. As described above, in FIG. 9A, since the angle θ of the section cd with respect to the wall W is equal to or greater than the threshold value, the determination unit 142 may determine to travel in the self-position estimation travel mode.

In FIG. 9B, sections 101a, 101a, 101a, 101a, 101a, 101a, 101a, 101a, 101a, 101a, 101a, 101a, 101a, 101a, 101a, 101a, 101a, 101a, 101a, 101a, 101a, 101a, 101a, 101a, 101a, 101a, and 101f of the travel plan route are substantially parallel to the wall W. , and section ef with respect to the wall W are less than or equal to the threshold.

As shown in FIG. 9B, all of n sections (section 101a, section ab, section bc, section cd) (section 101a, section ab, section bc, section cd) in order from the closest to the autonomous mobile device 101 on the travel plan route (for example, n=4) to the wall W is less than the threshold value, the determination unit 142 may determine to run in the along-the-wall running mode. As described above, in FIG. 9B, since the angles with respect to the wall W in the section 101a, the section ab, the section bc, and the section cd are less than the threshold value, the determination unit 142 may determine that the vehicle travels in the self-position estimation travel mode. .

The determination methods described with reference to FIGS. 9A and 9B may be used alone, or may be used in combination with other determination methods.

The determination unit 142 may combine a plurality of determination methods as described below to determine in which running mode, the self-position estimation running mode or the along-the-wall running mode, the vehicle is to be run.

For example, the determination unit 142 uses the determination method based on the distance between the planned travel route and the wall described in FIGS. And FIGS. 9A and 9B, at least two of the determination methods based on the angle of the travel route with respect to the wall are performed, and based on the determination results of the at least two performed determination methods, the self-position estimation travel mode and the wall It is determined in which running mode of the parallel running mode the vehicle should run. For example, if all of the determination results of the at least two determination methods that have been executed are in the wall-along running mode, the determination unit 142 determines to run in the wall-along running mode, and determines the wall-along running mode received from the running control unit 133 for running along the wall. A run command is output to the drive unit 161 . Further, when at least one of the determination results of the executed at least two determination methods is the self-position estimation running mode, the determination unit 142 determines to run in the self-position estimation running mode, and the running route received from the running control unit 124. A travel command for traveling the travel route planned by the planning unit 123 is output to the drive unit 161 .

Further, the determination unit 142 may determine whether to run in the self-position estimation running mode or the along-the-wall running mode based on an instruction received from the user or the outside. In addition, an area in which the autonomous mobile device 101 travels in the wall-along mode is set in the map information 152 in advance, and the determination unit 142 determines whether the autonomous mobile device 101 is in the wall-along mode in the area set in the map information 152. Then, it may be determined whether the vehicle is to be driven in the self-position estimation driving mode or the along-the-wall driving mode.

In addition, since there is a time lag between when the running mode switching unit 141 outputs the running command and when the driving unit 161 causes the autonomous running device 101 to run according to the running command, the calculated position of the autonomous running device 101 and the actual position A gap occurs between the autonomous mobile device 101 and the autonomous mobile device 101 . When the autonomous mobile device 101 travels along a wall, if the traveling speed of the autonomous mobile device 101 is high, the deviation due to the time difference increases and the amount of wheel slip increases, so the autonomous mobile device 101 may collide with the wall. be. In order to prevent a collision with a wall, the travel control unit 133 may lower the maximum speed of the autonomous mobile device 101 in the along-the-wall travel mode than the maximum speed of the autonomous mobile device 101 in the self-position estimation travel mode. That is, the maximum speed of the autonomous mobile device 101 in the along-the-wall traveling mode may be lower than the maximum speed of the autonomous mobile device 101 in the self-position estimation traveling mode.

In this way, by lowering the traveling speed in the wall-along traveling mode, it is possible to reduce the influence of the wheel slippage and the traveling instruction of the drive unit 161, and it is possible to perform precise traveling and prevent collision with the wall. can.

Further, the travel control unit 133 may increase the turning speed of the autonomous mobile device 101 in the along-the-wall traveling mode than the turning speed of the autonomous mobile device 101 in the self-position estimation traveling mode. That is, the turning speed of the autonomous mobile device 101 in the along-the-wall traveling mode may be greater than the turning speed of the autonomous mobile device 101 in the self-position estimation traveling mode. Further, the traveling control unit 133 may increase the acceleration of the autonomous mobile device 101 in the along-the-wall traveling mode more than the acceleration of the autonomous mobile device 101 in the self-position estimation traveling mode. That is, the acceleration of the autonomous mobile device 101 in the along-the-wall traveling mode may be greater than the acceleration of the autonomous mobile device 101 in the self-position estimation traveling mode. In this way, when driving in wall-aligning mode, by increasing the turning speed or acceleration and turning agilely, the feedback of the angle deviation with the wall is quickened, and the parallelism with the wall is maintained more accurately. You can run in the state.

Note that either one of the turning speed and the acceleration in the wall-along running mode may be changed, or both may be changed at the same time. Through these processes, it is possible to decelerate when approaching a wall, and to repeat turning motions more quickly and finely than usual.

According to the autonomous mobile device 101 according to the embodiment, it is possible to appropriately determine which of the self-position estimation traveling mode and the wall-along traveling mode to travel in, and switch the traveling mode to improve the resolution of the map. It is possible to suppress an increase in the computational load of , and realize precise running such as running along several centimeters along the wall.

It should be noted that the present invention is not limited to the above-described embodiment, but can be modified. can be replaced with a configuration that allows

101 Autonomous mobile device 111 Sensor 121 Autonomous travel control unit 122 Self position estimation unit 123 Travel route planning unit 124 Travel control unit 131 Along wall travel control unit 132 Wall detection unit 133 Travel control unit 141 Travel mode switching unit 142 Determining unit 143 Leaving operation Control unit 151 Storage unit 152 Map information 161 Driving unit

Claims (12)

In an autonomous mobile device that travels based on self-position estimation,
a sensor that measures the distance and direction to surrounding walls;
a wall detection unit that detects the wall from the distance and direction measured by the sensor;
a self-position estimation unit that estimates the self-position of the autonomous mobile device;
a travel route planning unit that plans a travel route based on the self-location and map information;
a traveling mode switching unit for switching between a self-position estimation traveling mode in which the vehicle travels based on the self-position estimation by the self-position estimating unit and a wall-along traveling mode in which the vehicle travels while maintaining a distance from the wall;
The traveling mode switching unit switches between the self-position estimation traveling mode and the along-the-wall traveling mode based on the traveling route and the detected wall. The autonomous mobile device according to claim 1, wherein the travel mode switching unit switches between the self-position estimation travel mode and the along-the-wall travel mode based on the distance between the travel route and the wall. The autonomous traveling according to claim 1 or 2, wherein the traveling mode switching unit switches between the self-position estimation traveling mode and the along-the-wall traveling mode based on the traveling route and a range based on the direction parallel to the wall. Device. The autonomous mobile device according to any one of claims 1 to 3, wherein the travel mode switching unit switches between the self-position estimation travel mode and the wall-along travel mode based on an angle of the travel route with respect to the wall. . The running mode switching unit performs at least two determinations out of a first determination, a second determination, and a third determination, and at least one of the determination results of the at least two determinations is the self-position estimation mode. If there is, switch the running mode to the self-position estimation mode,
The first determination determines whether to run in either the self-position estimation running mode or the wall-along running mode based on the distance between the running route and the wall;
The second determination determines whether to run in either the self-position estimation running mode or the wall-along running mode based on the range based on the running route and the direction parallel to the wall;
5. The method according to any one of claims 1 to 4, wherein the third determination determines whether to run in one of the self-position estimation running mode and the wall-along running mode based on the angle of the running route with respect to the wall. The autonomous mobile device according to any one of claims 1 to 3. 6. The distance from the autonomous mobile device to the obstacle in the traveling direction of the autonomous mobile device is equal to or greater than the distance required for the autonomous mobile device to leave the wall at the start of the movement to leave the wall. or the autonomous mobile device according to claim 1. 7. The autonomous mobile device according to any one of claims 1 to 6, further comprising a display for displaying the current travel mode. The autonomous mobile device according to any one of claims 1 to 7, further comprising a display unit that displays an angle of the travel route with respect to the wall. The autonomous mobile device according to any one of claims 1 to 8, wherein a maximum speed of the autonomous mobile device in the along-the-wall running mode is lower than a maximum speed of the autonomous mobile device in the self-position estimation running mode. The autonomous mobile device according to any one of claims 1 to 9, wherein a turning speed of the autonomous mobile device in the wall-along running mode is higher than a turning speed of the autonomous mobile device in the self-position estimation running mode. The autonomous mobile device according to any one of claims 1 to 10, wherein an acceleration of the autonomous mobile device during the wall-along running mode is greater than an acceleration of the autonomous mobile device during the self-position estimation running mode. In a control method for an autonomous mobile device that travels based on self-position estimation,
Measure the distance and direction to the surrounding walls,
detecting the wall from the measured distance and direction;
estimating the self-position of the autonomous mobile device;
planning a travel route based on the self-location and map information;
Based on the travel route and the detected wall, switching between a self-position estimation travel mode in which the vehicle travels based on self-position estimation and a wall-along travel mode in which the vehicle travels while maintaining a distance from the wall.
A control method comprising processing.

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