Mobile robot collision detection method

Abstract

The invention relates to the technical field of mobile robots, in particular to a mobile robot collision detection method, which defines a plurality of areas around the contour of a robot body, namely a stop area, a deceleration area and an approaching area. And if the number of the obstacle points in the stop area exceeds N, stopping the robot. If the number of the obstacle points in the deceleration area exceeds N, the maximum speed of the robot is reduced to S%. The approaching area estimates the collision time of the robot and the obstacle point according to the current speed of the robot, and if the time is less than M seconds, the speed of the robot is slowed down, so that the distance between the robot and the obstacle is always kept for M seconds. According to the method, the robot cost map does not need to be updated, the calculated amount is small, the response speed to obstacles is higher, meanwhile, a more flexible obstacle avoidance strategy is provided by setting the user-defined detection area, the defects of an existing mobile robot collision detection method are overcome, and user requirements are met.

Description

Technical Field

[0001] The present invention relates to the technical field of mobile robots, and in particular to a mobile robot collision detection method. Background Art

[0002] A mobile robot is a machine device that automatically performs work. It integrates the research results of multiple disciplines such as computer technology, information technology, communication technology, microelectronics technology, and robotics technology. It has multiple functions such as environmental perception, dynamic decision-making and planning, and behavior control and execution. At present, the collision detection of mobile robots based on ranging sensors is mainly based on two methods: one is to adopt a simple obstacle avoidance strategy, and the other is based on long-distance ranging sensors such as laser radar.

[0003] However, a simple obstacle avoidance strategy is adopted, and the robot is controlled to stop when the distance to the obstacle is less than a certain threshold. This method is too simple and crude. The same obstacle avoidance strategy is adopted for obstacles in different directions, and a flexible obstacle avoidance effect cannot be achieved. Based on long-distance ranging sensors such as lidar, obstacle information is added to the cost map during navigation, and the planning controller calculates and generates collision-avoiding paths and speed control instructions. This method needs to update the cost map to process more data, so it often does not respond in time during remote control operations or to sudden obstacles, and it also requires more calculations.

[0004] Existing mobile robot collision detection methods all have shortcomings and cannot meet user needs. Summary of the invention

[0005] The purpose of the present invention is to provide a mobile robot collision detection method, which solves the problem that the existing mobile robot collision detection methods are insufficient and cannot meet user needs.

[0006] To achieve the above object, the present invention provides a mobile robot collision detection method, comprising the following steps: Load polygonal obstacle avoidance area configuration file; Convert distance sensor data into obstacle point cloud information; The system checks whether there is a collision based on the area priority and adjusts the chassis speed based on the check result.

[0007] Wherein, loading the polygon obstacle avoidance area configuration file, the step further includes: Multiple areas are defined around the robot body contour, from the inside to the outside: approach area, stop area and deceleration area.

[0008] Wherein, checking whether there is a collision according to the area priority traversal, and adjusting and controlling the chassis speed according to the checking result, the step also includes: The area priorities from high to low are stop area, deceleration area and approach area.

[0009] Wherein, checking whether there is a collision according to the area priority traversal, and adjusting and controlling the chassis speed according to the checking result, the step also includes: Check whether the number of obstacle points in the stop area is greater than the minimum number of obstacle points N. If the number of obstacle points in the stop area is greater than the minimum number of obstacle points N, the chassis speed is modified to 0. Otherwise, the deceleration area check is performed.

[0010] Wherein, checking whether there is a collision according to the area priority traversal, and adjusting and controlling the chassis speed according to the checking result, the step also includes: Check whether the number of obstacle points in the deceleration area is greater than the minimum number of obstacle points N. If the number of obstacle points in the deceleration area is greater than the minimum number of obstacle points N, the chassis speed is modified to S% of the current target speed according to the settings. Otherwise, perform an approach area check.

[0011] Wherein, checking whether there is a collision according to the area priority traversal, and adjusting and controlling the chassis speed according to the checking result, the step also includes: In the approach area check, forward simulation is performed for M seconds according to the robot's target speed and direction at a certain time step interval. In each step simulation trajectory, check whether the number of obstacle points in the current approach area is greater than the minimum number of obstacle points N. If it is greater, record the current collision time as , and regenerate the speed command:

[0012] Maintain a distance of M seconds from obstacles.

[0013] Wherein, checking whether there is a collision according to the area priority traversal, and adjusting and controlling the chassis speed according to the checking result, the step also includes: If the number of obstacle points in all collision areas is less than the minimum number of obstacle points N, the original speed command is maintained.

[0014] A mobile robot collision detection method of the present invention defines multiple areas around the robot body contour, including a stop area, a deceleration area, and an approach area. Among them: stop area: if there are more than N obstacle points in this area, the robot will be stopped. Deceleration area: if there are more than N obstacle points in this area, the maximum speed of the robot will be reduced to S%. Approaching area: according to the current speed of the robot, the collision time between the robot and the obstacle point is estimated. If the time is less than M seconds, the robot speed will be slowed down so that the robot and the obstacle are always kept at a distance of M seconds. There is no need to update the robot cost map, the amount of calculation is small, and it has a faster response speed to obstacles. At the same time, a more flexible obstacle avoidance strategy is provided by setting a custom detection area. For example, when an obstacle appears on the side of the robot, it only needs to reduce the speed to pass safely without triggering a stop to avoid obstacles. It is not only applicable to 2D mobile robots, but can also be extended to other motion models such as 3D space, solving the shortcomings of existing mobile robot collision detection methods and meeting user needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below.

[0016] Figure 1 It is a schematic diagram of defining multiple areas around the robot body contour according to the first embodiment of the present invention.

[0017] Figure 2 4 is a flow chart of a mobile robot collision detection method according to a first embodiment of the present invention.

[0018] Figure 3 4 is a flowchart of the steps of the mobile robot collision detection method according to the first embodiment of the present invention. DETAILED DESCRIPTION

[0019] Embodiments of the present invention are described in detail below. Examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, but should not be construed as limiting the present invention.

[0020] The first embodiment of the present application is: See also Figures 1 to 3 ,in, Figure 1 It is a schematic diagram of defining multiple areas around the robot body contour according to the first embodiment of the present invention. Figure 2 4 is a flow chart of a mobile robot collision detection method according to a first embodiment of the present invention. Figure 3 1 is a flowchart of the steps of the mobile robot collision detection method of the first embodiment of the present invention. The present invention provides a mobile robot collision detection method: comprising the following steps: S101: Loading polygonal obstacle avoidance area configuration file; Specifically, read the configuration parameter file, take the center point of the robot as the coordinate origin, and configure multiple collision detection areas, from the inside to the outside: approach area, stop area and deceleration area. Figure 1 As shown, A, B, C, and D correspond to the coordinates of the top left, bottom left, bottom right, and top right vertices of the stop area. E, F, G, and H correspond to the coordinates of the top left, bottom left, bottom right, and top right vertices of the deceleration area. I, J, K, and L correspond to the coordinates of the top left, bottom left, bottom right, and top right vertices of the approach area.

[0021] S102: Converting distance sensor data into obstacle point cloud information; Specifically, the robot center point is used as the coordinate origin to convert the sensor distance data into obstacle point cloud information. Assume that the sensor data is ,in is the obstacle distance information, is the obstacle position information, The position information of the sensor in the robot coordinate system. Converted into point cloud information in the robot coordinate system ,

[0022] in: is the rotation matrix used to transform the sensor ranging point into the robot coordinate system.

[0023] It is the Cartesian coordinate representation of obstacle information in the sensor coordinate system.

[0024] is the translation vector, which translates the rotated point to the robot coordinate system.

[0025] S103: Check whether there is a collision according to the area priority traversal, and adjust and control the chassis speed according to the check result.

[0026] Specifically, according to the danger level, the obstacle area priority is set from high to low as the stop area, deceleration area, and approach area. And according to the area priority order, it is checked whether there is a collision, and the chassis speed is adjusted and controlled.

[0027] First, check whether the number of obstacle points in the stop area is greater than the minimum number of obstacle points N. If the number of obstacle points in the stop area is greater than the minimum number of obstacle points N, increase the chassis speed. Modify to 0:

[0028] Otherwise, perform a deceleration zone check.

[0029] Then check whether the number of obstacle points in the deceleration area is greater than the minimum number of obstacle points N. If the number of obstacle points in the deceleration area is greater than the minimum number of obstacle points N, modify the chassis speed to the current target speed according to the settings. S%: Otherwise, an approach area check is performed, where target_vel is the target speed and S% is the speed adjustment ratio.

[0030] In the approach area check, forward simulation is performed for M seconds according to the robot's target speed and direction at a certain time step interval. In each step simulation trajectory, check whether the number of obstacle points in the current approach area is greater than the minimum number of obstacle points N. If it is greater, record the current collision time as , and regenerate the speed command: Maintain a distance of M seconds from obstacles.

[0031] If the number of obstacle points in all collision areas is less than the minimum number of obstacle points N, the original speed command is maintained:

[0032] There is no need to update the robot cost map, the amount of calculation is small, and it has a faster response speed to obstacles. At the same time, by setting a custom detection area, a more flexible obstacle avoidance strategy is provided. For example, when an obstacle appears on the side of the robot, it only needs to reduce the speed to pass safely without triggering a stop to avoid obstacles. It is not only applicable to 2D mobile robots, but can also be extended to other motion models such as 3D space, solving the shortcomings of existing mobile robot collision detection methods and meeting user needs.

[0033] What is disclosed above is only one or more preferred embodiments of the present application, and cannot be used to limit the scope of rights of the present application. Ordinary technicians in this field can understand that all or part of the processes of implementing the above embodiments and equivalent changes made according to the claims of the present application are still within the scope covered by the present application.

Claims

1. A mobile robot collision detection method, characterized in that: The following steps are involved: Load polygonal obstacle avoidance area configuration file; Convert distance sensor data into obstacle point cloud information; The system checks whether there is a collision based on the area priority and adjusts the chassis speed based on the check result.

2. The mobile robot collision detection method according to claim 1, characterized in that: Loading a polygonal obstacle avoidance area configuration file, the steps further include: Multiple areas are defined around the robot body contour, from the inside to the outside: approach area, stop area and deceleration area.

3. The mobile robot collision detection method according to claim 2, characterized in that: Checking whether there is a collision according to the area priority traversal, and adjusting and controlling the chassis speed according to the check result, the step also includes: The area priorities from high to low are stop area, deceleration area and approach area.

4. The mobile robot collision detection method according to claim 3, characterized in that: Checking whether there is a collision according to the area priority traversal, and adjusting and controlling the chassis speed according to the check result, the step also includes: Check whether the number of obstacle points in the stop area is greater than the minimum number of obstacle points N. If the number of obstacle points in the stop area is greater than the minimum number of obstacle points N, the chassis speed is modified to 0. Otherwise, the deceleration area check is performed.

5. The mobile robot collision detection method according to claim 4, characterized in that: Checking whether there is a collision according to the area priority traversal, and adjusting and controlling the chassis speed according to the check result, the step also includes: Check whether the number of obstacle points in the deceleration area is greater than the minimum number of obstacle points N. If the number of obstacle points in the deceleration area is greater than the minimum number of obstacle points N, the chassis speed is modified to S% of the current target speed according to the settings. Otherwise, perform an approach area check.

6. The mobile robot collision detection method according to claim 5, characterized in that: Checking whether there is a collision according to the area priority traversal, and adjusting and controlling the chassis speed according to the check result, the step also includes: In the approach area check, forward simulation is performed for M seconds according to the robot's target speed and direction at a certain time step interval. In each step simulation trajectory, check whether the number of obstacle points in the current approach area is greater than the minimum number of obstacle points N. If it is greater, record the current collision time as , and regenerate the speed command: Maintain a distance of M seconds from obstacles.

7. The mobile robot collision detection method according to claim 6, characterized in that: Checking whether there is a collision according to the area priority traversal, and adjusting and controlling the chassis speed according to the check result, the step also includes: If the number of obstacle points in all collision areas is less than the minimum number of obstacle points N, the original speed command is maintained.

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