Mechanical arm obstacle avoidance path planning method and system

Abstract

The application relates to the technical field of mechanical arms, in particular to a mechanical arm obstacle avoidance path planning method and system, which comprises the following steps: acquiring initial parameters and a target position of a mechanical arm, calculating a running path of the mechanical arm during execution, modeling the mechanical arm in three-dimensional space by adopting a cylindrical envelope method to form a first cylindrical region, extending the first cylindrical region; acquiring a mechanical arm motion path model to form a second cylindrical region, separating the second cylindrical region from the first cylindrical region to obtain n mechanical arm operable space regions; when a current obstacle is a static obstacle, the following steps are executed, and when the current obstacle is a dynamic obstacle, the mechanical arm stops executing; modeling the static obstacle to form a spherical region; and executing from a non-overlapping space region. The mechanical arm obstacle avoidance path planning method and system are simple to calculate, high in safety performance, and suitable for extendable non-folding arm mechanical arms.

Description

Technical Field

[0001] This invention relates to the field of robotic arm technology, and in particular to a method and system for planning obstacle avoidance paths for robotic arms. Background Technology

[0002] An industrial robotic arm is a mechatronic device that mimics the functions of a human arm, wrist, and hand. It can move any object or tool according to time-varying spatial posture (position and orientation) requirements, thereby fulfilling the operational requirements of a specific industrial production process. Examples include clamping welding clamps or welding torches for spot welding or arc welding of automobile or motorcycle bodies; handling die-cast or stamped parts or components; performing laser cutting; spray painting; assembling mechanical parts, and so on.

[0003] In addition to the commonly used articulated robotic arms, there are also extendable non-articulated robotic arms. Extendable non-articulated robotic arms are less expensive than commonly used articulated robotic arms, and their structure and algorithms are simpler. On the other hand, the obstacle avoidance path planning methods and systems of commonly used articulated robotic arms are complex in structure and have high operating costs. Therefore, it is necessary to develop new obstacle avoidance path planning methods and systems for extendable non-articulated robotic arms. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a method and system for planning obstacle avoidance paths for robotic arms. The method and system for planning obstacle avoidance paths for robotic arms are simple to calculate, have high safety performance, and are applicable to extendable non-folding robotic arms.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0006] A method for obstacle avoidance path planning for a robotic arm, comprising:

[0007] Obtain the initial parameters and target position of the robotic arm at the current moment, and calculate the running path of the robotic arm under undisturbed conditions.

[0008] In three-dimensional space, the robotic arm is modeled using the cylindrical envelope method to form the first cylindrical region, thus obtaining the robotic arm model. The first cylindrical region is then extended according to the range of motion of the robotic arm.

[0009] Similarly, the cylindrical envelope method is used for modeling to obtain the motion path model of the robotic arm, forming a second cylindrical region. The second cylindrical region is divided into the first cylindrical region to obtain n operable space regions of the robotic arm. The n operable space regions of the robotic arm are sorted according to the length of the path from the robotic arm to the target position.

[0010] Obstacles are categorized into static and dynamic obstacles based on their motion state. Sensors detect these obstacles in real time. When the obstacle is static, the following steps are executed. When the obstacle is dynamic, the robotic arm stops executing.

[0011] Static obstacles are modeled in three-dimensional space using the sphere envelope method to obtain an obstacle model, forming a spherical region;

[0012] The spherical region is compared with the first cylindrical region to determine whether the spherical region exceeds the boundary of the first cylindrical region. If it does, the robotic arm stops running. When the spherical region does not exceed the first cylindrical region, the spherical region is compared with the second cylindrical region to obtain the space region that does not overlap with the second cylindrical region. The robotic arm follows the principle of proximity and obtains the robotic arm running path from the space region that does not overlap, and then executes it.

[0013] Furthermore, while the dynamic obstacle is perceived in real time by the sensor, the motion information of the obstacle is solved by combining the map difference method according to the relative position relationship between the obstacle and the robotic arm at different times. The dynamic obstacle will change over time, and the part that changes is the dynamic obstacle.

[0014] Furthermore, the sensing range of the sensor is the area of ​​the first cylindrical region.

[0015] Furthermore, the sensor can be a high-definition camera.

[0016] Furthermore, the running path includes the shortest path and the longest path, as well as an intermediate path located between the shortest path and the longest path.

[0017] The present invention also provides a robotic arm obstacle avoidance path planning system, which includes

[0018] The parameter acquisition module obtains the initial parameters and target position of the robotic arm at the current moment, and calculates the running path of the robotic arm under undisturbed conditions.

[0019] The robotic arm modeling module models the robotic arm in three-dimensional space using the cylindrical envelope method to form the first cylindrical region, thus obtaining the robotic arm model. Based on the robotic arm's range of motion, the first cylindrical region is extended.

[0020] The robotic arm motion path modeling module also uses the cylindrical envelope method to model and obtain the robotic arm motion path model, forming a second cylindrical region. The second cylindrical region is divided into the first cylindrical region to obtain n robotic arm run-out space regions. The n robotic arm run-out space regions are sorted according to the length of the path from the robotic arm to the target position.

[0021] The obstacle perception module classifies obstacles into static and dynamic obstacles based on their motion state. It uses sensors to perceive obstacles in real time. When the current obstacle is a static obstacle, the following steps are executed. When the current obstacle is a dynamic obstacle, the robotic arm stops executing.

[0022] The obstacle modeling module uses the sphere envelope method to model static obstacles in three-dimensional space, resulting in an obstacle model that forms a spherical region.

[0023] The comparison execution module compares the spherical region with the first cylindrical region to determine whether the spherical region exceeds the boundary of the first cylindrical region. If it does, the robotic arm stops running. When the spherical region does not exceed the first cylindrical region, it compares the spherical region with the second cylindrical region to obtain the space region that does not overlap with the second cylindrical region. The robotic arm follows the principle of proximity and obtains the robotic arm running path from the space region that does not overlap, and then executes it.

[0024] The beneficial effects of this invention are as follows: In practical use, the initial parameters and target position of the robotic arm must first be obtained to calculate the running path of the robotic arm under undisturbed conditions. Then, the robotic arm is modeled in three-dimensional space using the cylindrical envelope method, forming an extended first cylindrical region, which is the area where the robotic arm can move. Similarly, the motion path model of the robotic arm is obtained. The first cylindrical region is then divided into n operable space regions for the robotic arm, where the first space region represents the longest path from the robotic arm to the target position, and the nth space region represents the shortest path from the robotic arm to the target position. Finally, obstacles are considered. For perception and differentiation, dynamic obstacles are treated with static defense. When the obstacle is static, a spherical region is formed using the obstacle model. This spherical region is compared with the first cylindrical region. When the spherical region exceeds the first cylindrical region, it means that the robotic arm will collide with the dynamic obstacle regardless of its running path. At this time, the robotic arm stops executing. The spherical region is then compared with the second cylindrical region. When the obstacle does not occupy the nth spatial region, the robotic arm still executes the shortest path. When the obstacle occupies the nth spatial region, the robotic arm selects the spatial region closest to the occupied spatial region and executes the running path closest to the occupied spatial region. Attached Figure Description

[0025] Figure 1 This is a flowchart of a robotic arm obstacle avoidance path planning method according to the present invention;

[0026] Figure 2 This is a flowchart of a robotic arm obstacle avoidance path planning system according to the present invention. Detailed Implementation

[0027] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to embodiments and accompanying drawings. The content mentioned in the embodiments is not intended to limit the present invention.

[0028] like Figure 1 As shown in the figure, the obstacle avoidance path planning method for a robotic arm provided in this embodiment includes the following steps:

[0029] S100: Obtain the initial parameters and target position of the robotic arm at the current moment, and calculate the running path of the robotic arm under undisturbed conditions.

[0030] S200: The robotic arm is modeled in three-dimensional space using the cylindrical envelope method to form the first cylindrical region, thus obtaining the robotic arm model. The first cylindrical region is then extended according to the range of motion of the robotic arm.

[0031] S300: The cylindrical envelope method is also used for modeling to obtain the motion path model of the robotic arm, forming a second cylindrical region. The second cylindrical region is divided into the first cylindrical region to obtain n operable space regions of the robotic arm. The n operable space regions of the robotic arm are sorted according to the length of the path from the robotic arm to the target position.

[0032] S400: Based on the movement state of obstacles, they are divided into static obstacles and dynamic obstacles. The sensors detect them in real time. When the current obstacle is a static obstacle, the following steps are executed. When the current obstacle is a dynamic obstacle, the robotic arm stops executing.

[0033] S500: Static obstacles are modeled in three-dimensional space using the sphere envelope method to obtain an obstacle model, forming a spherical region;

[0034] S600: Compare the spherical region with the first cylindrical region to determine whether the spherical region exceeds the boundary of the first cylindrical region. If it does, the robotic arm stops running. When the spherical region does not exceed the first cylindrical region, compare the spherical region with the second cylindrical region to obtain the space region that does not overlap with the second cylindrical region. The robotic arm follows the principle of proximity and obtains the robotic arm running path from the space region that does not overlap, and executes it.

[0035] In practical use, the initial parameters and target position of the robotic arm must first be obtained to calculate its running path under undisturbed conditions. Then, the robotic arm is modeled in 3D space using the cylindrical envelope method, forming an extended first cylindrical region, which represents the area where the robotic arm can move. Similarly, the motion path model of the robotic arm is obtained. The first cylindrical region is then divided into n operable spatial regions for the robotic arm, where the first spatial region represents the longest path from the robotic arm to the target position, and the nth spatial region represents the shortest path. Finally, obstacle perception is performed. To differentiate between dynamic and static obstacles, a static defense approach is used. When the obstacle is static, a spherical region is formed using the obstacle model. This spherical region is then compared with the first cylindrical region. If the spherical region exceeds the first cylindrical region, it means that the robotic arm will collide with the dynamic obstacle regardless of its path. At this point, the robotic arm stops executing. The spherical region is then compared with the second cylindrical region. If the obstacle does not occupy the nth spatial region, the robotic arm still executes the shortest path. If the obstacle occupies the nth spatial region, the robotic arm selects the spatial region closest to the occupied region and executes the path closest to the occupied region.

[0036] like Figure 1 As shown, the dynamic obstacle is sensed in real time by sensors, and the motion information of the obstacle is solved by combining map difference method based on the relative positional relationship between the obstacle and the robotic arm at different times. The dynamic obstacle changes over time, and the parts that change are the dynamic obstacles. In actual use, by combining sensors with map difference method, it is possible to determine whether an obstacle is a dynamic obstacle.

[0037] like Figure 1 As shown, the sensing range of the sensor is the area of ​​the first cylinder. In actual use, the sensing range of the sensor is limited to ensure that as long as the sensor detects an obstacle, the obstacle is within the area of ​​the first cylinder, which facilitates subsequent operations on the obstacle.

[0038] like Figure 1 As shown, the sensor employs a high-definition camera. In practical use, the use of a high-definition camera enables timely identification of obstacles that intrude into the sensing range.

[0039] like Figure 1 As shown, the operating path includes the shortest path, the longest path, and an intermediate path between the shortest and longest paths. In actual use, the operating path encompasses all the operating paths of the robotic arm for parameter acquisition.

[0040] like Figure 2As shown, this embodiment also provides a robotic arm obstacle avoidance path planning system, which includes:

[0041] Parameter acquisition module 1 acquires the initial parameters and target position of the robotic arm at the current moment, and calculates the running path of the robotic arm under undisturbed conditions.

[0042] The robotic arm modeling module 2 models the robotic arm in three-dimensional space using the cylindrical envelope method to form a first cylindrical region, thus obtaining the robotic arm model. Based on the movable range of the robotic arm, the first cylindrical region is extended.

[0043] The robotic arm motion path modeling module 3 also uses the cylindrical envelope method to model and obtain the robotic arm motion path model, forming a second cylindrical region. The second cylindrical region is divided into the first cylindrical region to obtain n robotic arm run-out space regions. The n robotic arm run-out space regions are sorted according to the path length from the robotic arm to the target position.

[0044] The obstacle perception module 4 classifies obstacles into static and dynamic obstacles based on their motion state and uses sensors to perceive them in real time. When the current obstacle is a static obstacle, the following steps are executed; when the current obstacle is a dynamic obstacle, the robotic arm stops executing.

[0045] Obstacle modeling module 5 uses the sphere envelope method to model static obstacles in three-dimensional space, obtaining obstacle models and forming spherical regions;

[0046] The comparison execution module 6 compares the spherical region with the first cylindrical region to determine whether the spherical region exceeds the boundary of the first cylindrical region. If it does, the robotic arm stops running. When the spherical region does not exceed the first cylindrical region, it compares the spherical region with the second cylindrical region to obtain the space region that does not overlap with the second cylindrical region. The robotic arm follows the principle of proximity and obtains the robotic arm running path from the space region that does not overlap, and then executes it.

[0047] In practical use, the initial parameters and target position of the robotic arm are first obtained through parameter acquisition module 1, and the running path of the robotic arm under undisturbed conditions is calculated. Then, the robotic arm modeling module 2 uses the cylindrical envelope method to model the robotic arm, obtaining the robotic arm model. Based on the robotic arm's range of motion, the first cylindrical region is extended. Then, the robotic arm motion path modeling module 3 also uses the cylindrical envelope method to model the robotic arm, obtaining the robotic arm motion path model and forming a second cylindrical region. The second cylindrical region is then divided into n operable space regions for the robotic arm, where the first space region... The domain represents the longest path from the robotic arm to the target position, and the nth spatial region represents the shortest path from the robotic arm to the target position. Then, the obstacle perception module 4 perceives obstacles and classifies them. If the current obstacle is a static obstacle, the following steps continue. If the current obstacle is a dynamic obstacle, the robotic arm stops execution to prevent collisions with dynamic obstacles during its operation. At the same time, the robotic arm is kept still to minimize damage caused by collisions. After confirming that the obstacle is a static obstacle, the robotic arm's running path is finally obtained through the obstacle modeling module 5 and the comparison execution module 6 and executed.

[0048] The obstacle avoidance path planning method and system of this application are simple to calculate, have high safety performance, and are applicable to extendable non-folding robotic arms.

[0049] All technical features in this embodiment can be freely combined according to actual needs.

[0050] The above embodiments are preferred implementations of the present invention. In addition, other implementations are also included. Any obvious substitutions without departing from the concept of the present invention are within the protection scope of the present invention.

Claims

1. A method for obstacle avoidance path planning for a robotic arm, applicable to extendable non-folding robotic arms, characterized in that: include Obtain the initial parameters and target position of the robotic arm at the current moment, and calculate the running path of the robotic arm under undisturbed conditions. In three-dimensional space, the robotic arm is modeled using the cylindrical envelope method to form the first cylindrical region, thus obtaining the robotic arm model. The first cylindrical region is then extended according to the range of motion of the robotic arm. Similarly, the cylindrical envelope method is used for modeling to obtain the motion path model of the robotic arm, forming a second cylindrical region. The second cylindrical region is divided into the first cylindrical region to obtain n operable space regions of the robotic arm. The n operable space regions of the robotic arm are sorted according to the length of the path from the robotic arm to the target position. Obstacles are categorized into static and dynamic obstacles based on their motion state. Sensors detect these obstacles in real time. When the obstacle is static, the following steps are executed. When the obstacle is dynamic, the robotic arm stops executing. Static obstacles are modeled in three-dimensional space using the sphere envelope method to obtain an obstacle model, forming a spherical region; The spherical region is compared with the first cylindrical region to determine whether the spherical region exceeds the boundary of the first cylindrical region. If it does, the robotic arm stops running. When the spherical region does not exceed the first cylindrical region, the spherical region is compared with the second cylindrical region to obtain the space region that does not overlap with the second cylindrical region. The robotic arm follows the principle of proximity and obtains the robotic arm running path from the space region that does not overlap, and then executes it. The dynamic obstacle is sensed in real time by sensors, and the motion information of the obstacle is solved by combining the map difference method based on the relative position relationship between the obstacle and the robotic arm at different times. The dynamic obstacle will change over time, and the part that changes is the dynamic obstacle. The sensing range of the sensor is the area of ​​the first cylindrical region; The sensor is a high-definition camera; The running path includes the shortest path and the longest path, as well as an intermediate path between the shortest path and the longest path.

2. A robotic arm obstacle avoidance path planning system, used to implement the robotic arm obstacle avoidance path planning method of claim 1, characterized in that, include: The parameter acquisition module obtains the initial parameters and target position of the robotic arm at the current moment, and calculates the running path of the robotic arm under undisturbed conditions. The robotic arm modeling module models the robotic arm in three-dimensional space using the cylindrical envelope method to form the first cylindrical region, thus obtaining the robotic arm model. Based on the robotic arm's range of motion, the first cylindrical region is extended. The robotic arm motion path modeling module also uses the cylindrical envelope method to model and obtain the robotic arm motion path model, forming a second cylindrical region. The second cylindrical region is divided into the first cylindrical region to obtain n robotic arm run-out space regions. The n robotic arm run-out space regions are sorted according to the length of the path from the robotic arm to the target position. The obstacle perception module classifies obstacles into static and dynamic obstacles based on their motion state. It uses sensors to perceive obstacles in real time. When the current obstacle is a static obstacle, the following steps are executed. When the current obstacle is a dynamic obstacle, the robotic arm stops executing. The obstacle modeling module uses the sphere envelope method to model static obstacles in three-dimensional space, resulting in an obstacle model that forms a spherical region. The comparison execution module compares the spherical region with the first cylindrical region to determine whether the spherical region exceeds the boundary of the first cylindrical region. If it does, the robotic arm stops running. When the spherical region does not exceed the first cylindrical region, it compares the spherical region with the second cylindrical region to obtain the space region that does not overlap with the second cylindrical region. The robotic arm follows the principle of proximity and obtains the robotic arm running path from the space region that does not overlap, and then executes it.

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