WO2024041648A1 - Trajectory planning method and apparatus for robot end - Google Patents

Abstract

A trajectory planning method for a robot end. The method comprises: performing smooth fitting on several discrete path nodes of a robot end, so as to obtain a planned path of the robot end in a Cartesian space; under a kinematic constraint condition of the Cartesian space of the robot end, according to the planned path, obtaining a planned trajectory of the robot end in the Cartesian space by means of speed planning; obtaining joint nodes of the robot end in a robot joint space according to the planned trajectory of the robot end in the Cartesian space; and under a kinematic constraint condition of each shaft of a robot and according to the joint nodes, obtaining a planned trajectory of the robot end in the robot joint space. By means of the planning method, the requirement for the position precision of a Cartesian space, the requirement for a kinematic constraint of the motion in the Cartesian space, and the requirement for a kinematic constraint of each shaft of a robot are decoupled, and a planned trajectory meets the requirements, thereby improving the motion performance of the robot. Further provided are a trajectory planning apparatus for a robot end, and a computing device and a computer-readable storage medium.

Description

A planning method and device for the terminal trajectory of a robot

This application claims the priority of the prior country application. The prior country application is China. The application number of the prior country application is 202211035164.9 and the filing date is August 26, 2022. The entire content of the prior country application is incorporated herein by reference.

Technical field

The present application relates to the technical field related to motion control, and in particular to a planning method and device for the end trajectory of a robot.

Background technique

The trajectory planning of the robot end (also called the execution end) needs to consider the requirements of the Cartesian space position, the requirements of the Cartesian space motion and the requirements of the various axis motions of the robot joint space. Among them, the requirements of the Cartesian space position include the position The requirements for smoothness and accuracy. The requirements for Cartesian space motion include the speed constraints and speed continuity requirements of the robot's movement in Cartesian space. The requirements for axis motion include the kinematic constraints of the axis as well as the speed continuity and acceleration continuity, and even Includes requirements for jerk continuity.

The existing technology does not decouple the above three requirements in the planning process. In the planning process, at least two of the above three requirements are often considered at the same time, causing these three requirements to interact with each other, affecting the planning effect, and even planning out. There are problems such as position deviation and shaft vibration during the movement of the trajectory.

Contents of the invention

In view of this, embodiments of the present application provide a method and device for planning a terminal trajectory of a robot. The technical solution of this application decouples the requirements of the Cartesian space position, the requirements of the Cartesian space motion and the requirements of the motion of each axis of the robot joint space in the trajectory planning process of the robot end, so that the final planned trajectory meets the Cartesian requirements. The smoothness and accuracy requirements of the spatial position, the constraints and velocity continuity requirements of the Cartesian space motion speed, and the constraints and continuity requirements of the speed, acceleration and jerk of each axis of the robot joint space.

In the first aspect, embodiments of the present application provide a method for planning the end trajectory of a robot, including: obtaining several discrete path nodes at the end of the robot, where the coordinates of the path nodes are poses in Cartesian space. The space includes a Cartesian position space and a Cartesian attitude space, and the pose includes a position and an attitude; the path nodes are smoothly fitted to obtain the planned path of the robot end in the Cartesian space; the Cartesian space at the end of the robot is Under kinematic constraints, the planned trajectory of the robot end in Cartesian space is obtained by using speed planning according to the planned path. The planned trajectory of the planned trajectory in Cartesian space is continuous; according to the planned trajectory of the robot end in Cartesian space, we obtain The joint nodes of the robot's end in the robot's joint space. The joint nodes are the key points of the movement trajectory of the robot's end in its joint space, and its coordinates are the coordinates of the robot's joint space; the kinematic constraints on each axis of the robot Under the conditions, the planned trajectory of the robot end in the joint space is obtained according to the joint nodes, and the speed, acceleration and jerk of the planned trajectory are continuous.

From the above, through Cartesian space path planning, Cartesian space trajectory planning and joint space trajectory planning on the machine In the process of trajectory planning of the robot end, the requirements for Cartesian space position accuracy, the kinematic constraints of Cartesian space motion and the kinematic constraints of each axis of the robot are decoupled, and the final planning is improved in the Cartesian path planning. Regarding the position accuracy of the trajectory, trajectory planning in Cartesian space enables the final planned trajectory to meet the kinematic constraints of Cartesian space, and trajectory planning in joint space enables the motion of each axis to meet the kinematic constraints, thereby improving the end trajectory motion performance of the robot.

In a possible implementation of the first aspect, the posture in the pose is represented by a continuous Euler angle, and the continuous Euler angle of a path node is equal to the continuous Euler angle of the previous path node and the continuous Euler angle of the path node. The sum of Euler angle rotation angles of a node. The Euler angle rotation angle of a path node is equal to the forward rotation angle from the previous path node to the Euler angle of the path node.

From the above, continuous Euler angles are used to represent the attitude. During trajectory planning in Cartesian space, the problem that trajectory interpolation cannot be performed due to the existence of singular points in traditional Euler angles is solved, and the continuity of the attitude is achieved.

In a possible implementation of the first aspect, the process of smoothly fitting the path nodes includes one of the following: using line segments and arcs to smoothly fit the path nodes; using polynomials or B-splines to smoothly fit the path nodes. The path nodes perform smooth fitting. In regular paths, line segments and arcs are used to smoothly fit the path nodes; in irregular paths, polynomials or B-splines are used to smoothly fit the path nodes.

From the above, by using line segments and arcs to smoothly fit the path nodes or using polynomials or B-splines to smoothly fit the path nodes, the position on the planned path can be smoothed and the accuracy requirements of the motion path can be met. .

In a possible implementation of the first aspect, under the kinematic constraints of the Cartesian space at the end of the robot, velocity planning is used to obtain the planned trajectory of the end of the robot in Cartesian space according to the planned path, including : According to the pose of each path point of the planned path, the position path length and angular path length of each path point are obtained, and the position path length and the angular path length constitute the coordinates of the path space, a The position path length of a path point is the length of the planned path from the first path point to the path point in Cartesian position space, and the angular path length of a path point is from the Cartesian attitude space. The length of the planned path from the first path point to the path point; converting the kinematic constraints of the Cartesian space at the end of the robot into the kinematic constraints of the path space; kinematics in the path space Under constraint conditions, speed planning is used to obtain the planned trajectory of the robot end in the distance space according to the coordinates of the distance space, and the speed of the robot end in the distance space is continuous; the robot end is obtained according to the planned trajectory of the distance space. The planning trajectory of the human end in Cartesian space.

From the above, by converting the posture of each path point in the planned path into the coordinates of the two-dimensional journey space for path trajectory planning, and then converting it into the trajectory of the Cartesian space, not only the planned trajectory of the Cartesian space satisfies the end of the robot The kinematic constraints of the Cartesian space realize the velocity continuity of the planned trajectory in the Cartesian space, while solving the singular point problem in the interpolation process of Euler angles and reducing the complexity of trajectory synchronization.

In a possible implementation of the first aspect, under the kinematic constraints of the Cartesian space at the end of the robot, velocity planning is used to obtain the planned trajectory of the end of the robot in Cartesian space according to the planned path, including : According to the pose of each path point of the planned path, obtain the path length of each path point on each coordinate axis of the Cartesian position space, and form the coordinates of the path space of the planned path, a The length of the path point on a coordinate axis in Cartesian space is the length of the planned path from the first path point to the path point projected on the coordinate axis; the flute at the end of the robot is Kinematic constraints in Karl space are converted into kinematic constraints in the path space; kinematic constraints in the path space Under the condition, the planned trajectory of the robot end in the distance space is obtained by using speed planning according to the coordinates of the distance space, and the speed of the robot end in the distance space is continuous; the robot is obtained according to the planned trajectory of the distance space The planned trajectory of the end in Cartesian space.

From the above, by converting the posture of each path point in the planned path into the coordinates of the multi-dimensional journey space for path trajectory planning, and then converting it into the trajectory of the Cartesian space, not only the planned trajectory of the Cartesian space satisfies the end of the robot The kinematic constraints of Cartesian space realize the velocity continuity of the planned trajectory in Cartesian space, and at the same time solve the singular point problem in the interpolation process of Euler angles.

In a possible implementation of the first aspect, obtaining the joint nodes of the robot end in the robot joint space according to the planned trajectory of the robot end in Cartesian space includes: according to the planned trajectory of the robot end in Cartesian space Plan the trajectory and obtain the trajectory nodes according to the robot end in Cartesian space. The trajectory nodes are the key points of the movement trajectory of the robot end in Cartesian space; use the trajectory nodes as the joint nodes and use the kinematic inverse The solution converts the pose of the trajectory node into the coordinates of the joint node in the robot joint space.

From the above, the key points of the joint space are obtained based on the inverse kinematics solution, which provides a basis for trajectory planning in the joint space.

In a possible implementation of the first aspect, obtaining the planned trajectory of the end of the robot in its joint space according to the joint nodes under the kinematic constraints of each axis of the robot includes: Under the kinematic constraints, according to the coordinates of the joint nodes in the robot's joint space, speed planning is used to obtain a planned trajectory of each axis of the robot in its joint space, and based on this, the planned trajectory of each axis of the robot in its joint space is obtained. The motion duration between adjacent joint nodes; for any pair of adjacent joint nodes, the longest time among the motion durations of each axis of the robot between the pair of adjacent joint nodes is regarded as the motion duration between the pair of adjacent joint nodes. Synchronization duration; According to the synchronization duration of the robot between each pair of adjacent joint nodes and the coordinates of the joint nodes in the robot's joint space, the speed planning of the robot is obtained respectively under the kinematic constraints of each axis of the robot. The quadratic planned trajectory of each axis in its joint space is used as the planned trajectory of the robot end in its joint space. In this planned trajectory, the speed, acceleration and jerk of each axis of the robot are continuous.

From the above, under the kinematic constraints of each axis of the robot, through the trajectory planning of the secondary joint space, the trajectory synchronization of each axis in the joint space is achieved, so that the motion performance of the robot based on the planned trajectory is improved, and the final trajectory satisfies Realize the constraints and continuity requirements of speed, acceleration and jerk on each axis of the robot, and reduce the vibration of each axis of the robot.

In the second aspect, embodiments of the present application provide a planning device for a robot end trajectory, including: a node acquisition module for acquiring several discrete path nodes at the end of the robot, the coordinates of the path nodes are at The pose of the Cartesian space, the Cartesian space includes the Cartesian position space and the Cartesian attitude space, the pose includes the position and the attitude; the path smoothing module is used to perform smooth fitting on the path nodes, and obtain the Cartesian end position of the robot. The planned path in Karl space; the Cartesian trajectory planning module is used to obtain the planned trajectory of the robot end in Cartesian space by using speed planning according to the planned path under the kinematic constraints of the Cartesian space at the end of the robot; motion The inverse solution module is used to obtain the joint nodes of the robot end in the robot joint space based on the planned trajectory of the robot end in Cartesian space. The joint nodes are the key points of the motion trajectory of the robot end in its joint space. , whose coordinates are the coordinates of the robot's joint space; the joint trajectory planning module is used to obtain the planning of the robot's end in its joint space based on the joint nodes under the kinematic constraints of each axis of the robot. trajectory.

From the above, through Cartesian space path planning, Cartesian space trajectory planning and joint space trajectory planning, in the trajectory planning process of the robot end, the requirements for Cartesian space position accuracy, the kinematic constraint requirements of Cartesian space motion and the robot The kinematic constraints of each axis require decoupling. In Cartesian path planning, the position accuracy of the final planned trajectory is improved. In Cartesian space trajectory planning, the final planned trajectory satisfies the kinematic constraints of Cartesian space. In the joint space trajectory, The motion of each axis is planned to meet the kinematic constraints, thereby improving the robot's terminal trajectory motion performance.

In a possible implementation of the second aspect, the posture in the posture is represented by a continuous Euler angle, and the continuous Euler angle of a path node is equal to the continuous Euler angle of the previous path node and the continuous Euler angle of the path node. The sum of Euler angle rotation angles of a node. The Euler angle rotation angle of a path node is equal to the forward rotation angle from the previous path node to the Euler angle of the path node.

From the above, continuous Euler angles are used to represent the attitude. During trajectory planning in Cartesian space, the problem that trajectory interpolation cannot be performed due to the existence of singular points in traditional Euler angles is solved, and the continuity of the attitude is achieved.

In a possible implementation of the second aspect, the process for the path planning module to smoothly fit the path nodes includes one of the following: using line segments and arcs to smoothly fit the path nodes; using polynomials or B Splines provide a smooth fit to the path nodes. In regular paths, line segments and arcs are used to smoothly fit the path nodes; in irregular paths, polynomials or B-splines are used to smoothly fit the path nodes.

From the above, by using line segments and arcs to smoothly fit the path nodes or using polynomials or B-splines to smoothly fit the path nodes, the position on the planned path can be smoothed and the accuracy requirements of the motion path can be met. .

In a possible implementation of the second aspect, the Cartesian trajectory planning module is specifically configured to: obtain the positional path length and angular path of each path point according to the posture of each path point of the planned path. Length, the coordinates of the path space composed of the position path length and the angular path length. The position path length of a path point is the plan from the first path point to the path point in the Cartesian position space. The length of the path, the angular path length of a path point is the length of the planned path from the first path point to the path point in Cartesian attitude space; the kinematic constraints of the Cartesian space at the end of the robot The conditions are converted into kinematic constraints of the distance space; under the kinematic constraints of the distance space, speed planning is used to obtain the planned trajectory of the robot end in the distance space according to the coordinates of the distance space, and the mechanical The speed of the human end in the journey space is continuous; the planned trajectory of the robot end in the Cartesian space is obtained according to the planned trajectory of the journey space.

From the above, by converting the posture of each path point in the planned path into the coordinates of the two-dimensional journey space for path trajectory planning, and then converting it into the trajectory of the Cartesian space, not only the planned trajectory of the Cartesian space satisfies the end of the robot The kinematic constraints of the Cartesian space realize the velocity continuity of the planned trajectory in the Cartesian space, while solving the singular point problem in the interpolation process of Euler angles and reducing the complexity of trajectory synchronization.

In a possible implementation of the second aspect, the Cartesian trajectory planning module is specifically configured to: according to the pose of each path point of the planned path, obtain the Cartesian position space of each path point. The length of the journey on each coordinate axis and the coordinates of the journey space that constitute the planned path. The length of the journey of a path point on a coordinate axis of the Cartesian space is all the distances from the first path point to the path point. The length of the projected path of the planned path on the coordinate axis; convert the kinematic constraints of the Cartesian space at the end of the robot into the kinematic constraints of the path space; kinematic constraints of the path space below, according to the The coordinates of the distance space are obtained by using speed planning to obtain the planned trajectory of the robot end in the distance space, and the speed of the robot end in the distance space is continuous; according to the planned trajectory of the distance space, the planned trajectory of the robot end in Cartesian space is obtained Plan the trajectory.

From the above, by converting the posture of each path point in the planned path into the coordinates of the multi-dimensional journey space for path trajectory planning, and then converting it into the trajectory of the Cartesian space, not only the planned trajectory of the Cartesian space satisfies the robot The kinematic constraints of the Cartesian space at the end realize the velocity continuity of the planned trajectory in the Cartesian space, and at the same time solve the singular point problem in the interpolation process of Euler angles.

In a possible implementation of the second aspect, the motion inverse solution module is specifically configured to include: according to the planned trajectory of the robot end in Cartesian space, obtain the trajectory node of the robot end in Cartesian space, the trajectory node is the key point of the movement trajectory of the robot end in Cartesian space; the trajectory node is regarded as the joint node, and the inverse kinematics solution is used to convert the pose of the trajectory node into the joint node of the robot. Coordinates in joint space.

From the above, the key points of the joint space are obtained based on the inverse kinematics solution, which provides a basis for trajectory planning in the joint space.

In a possible implementation of the second aspect, the joint trajectory planning module is specifically configured to: under the kinematic constraints of each axis of the robot, use velocity planning to obtain the coordinates of the joint nodes in the joint space of the robot respectively. A planned trajectory of each axis of the robot in its joint space, and based on this, the movement duration of each axis of the robot between adjacent joint nodes is obtained; for any pair of adjacent joint nodes, the pair of adjacent joint nodes is The longest time of the movement duration of each axis of the robot between the joint nodes is used as the synchronization duration between the pair of adjacent joint nodes; according to the synchronization duration of the robot between each pair of adjacent joint nodes and the joint node's The coordinates of the robot's joint space are used to obtain the secondary planning trajectory of each axis of the robot in its joint space using speed planning under the kinematic constraints of each axis of the robot, and used as the planning of the robot's end in its joint space. Trajectory, the velocity, acceleration and jerk of each axis of the robot in the planned trajectory are continuous.

From the above, under the kinematic constraints of each axis of the robot, through the trajectory planning of the secondary joint space, the trajectory synchronization of each axis in the joint space is achieved, so that the motion performance of the robot based on the planned trajectory is improved, and the final trajectory satisfies Realize the constraints and continuity requirements of speed, acceleration and jerk on each axis of the robot, and reduce the vibration of each axis of the robot.

In a third aspect, embodiments of the present application provide a computing device, including:

bus;

A communication interface connected to the bus;

at least one processor connected to the bus; and

At least one memory is connected to the bus and stores program instructions. When executed by the at least one processor, the program instructions cause the at least one processor to execute any one of the embodiments of the first aspect of the present application.

In a fourth aspect, embodiments of the present application provide a computer-readable storage medium on which program instructions are stored. When executed by a computer, the program instructions cause the computer to execute any one of the embodiments described in the first aspect of the application.

Description of drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required to be used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present application and therefore do not It should be regarded as a limitation of the scope. For those of ordinary skill in the art, other relevant drawings can be obtained based on these drawings without exerting creative efforts.

Figure 1 is a schematic flow chart of Embodiment 1 of a robot end trajectory planning method of the present application;

Figure 2 is a schematic flow chart of Embodiment 2 of a robot end trajectory planning method of the present application;

Figure 3 is a schematic structural diagram of Embodiment 1 of a robot end trajectory planning device of the present application;

Figure 4 is a schematic structural diagram of Embodiment 2 of a robot end trajectory planning device of the present application;

Figure 5 is a schematic structural diagram of a computing device according to various embodiments of the present application.

Detailed ways

In the following description, reference is made to "some embodiments" which describe a subset of all possible embodiments, but it is understood that "some embodiments" may be the same subset or a different subset of all possible embodiments, and Can be combined with each other without conflict.

In the following description, the terms "first\second\third, etc." or module A, module B, module C, etc. are only used to distinguish similar objects or to distinguish different embodiments. Representing a specific ordering of objects, it will be understood that the specific order or sequence may be interchanged where permitted so that the embodiments of the application described herein can be practiced in an order other than that illustrated or described herein.

In the following description, the labels indicating steps involved, such as S110, S120, etc., do not necessarily mean that this step will be executed. If permitted, the order of the preceding and following steps can be interchanged, or executed at the same time.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this application belongs. The terms used herein are only for the purpose of describing the embodiments of the present application and are not intended to limit the present application.

Some terms used in the embodiments of this application are described below.

Cartesian space, Cartesian space coordinates: Cartesian space includes Cartesian position space and Cartesian attitude space. The coordinates of Descartes space are poses, including position coordinates and attitude coordinates; Descartes position space is a rectangular coordinate space, and position coordinates are three-dimensional rectangular coordinates, the Cartesian attitude space is the rotation space of the object, and the attitude coordinates represent the rotation angle of the object's current position relative to the object at the origin.

Robot joint space: The space composed of each axis of the robot. Its coordinates are the positions of each axis of the robot. The axes include translation axes and rotation axes. In this application, robot and robot have the same meaning.

Speed planner: A device for planning the trajectory and speed of moving objects. It plans the speed and trajectory of objects through trajectory interpolation. During speed planning, the speed and acceleration of each point are maintained continuously and obey kinematic constraints. The velocity planner can plan trajectories in Cartesian space as well as trajectories in other spaces. When planning, describe velocity as an expression of time, such as a polynomial based on time.

Path and path nodes, trajectory and trajectory nodes, and joint nodes: The path is composed of position relationships, excluding the relationship between each point on the path and time. Path nodes are key points on the path, points that determine the path trend. The trajectory does not include the position relationship, but also the relationship between each point on the trajectory and time. The trajectory nodes are the key points on the trajectory in the Cartesian space, which determine the trend of the trajectory in the Cartesian space. The joint nodes are the key points on the trajectory in the joint space, which determine joint The trend of spatial trajectories.

Embodiments of the present application provide a method and device for planning the trajectory of the end of a robot. The technical solution includes: obtaining several discrete path nodes at the end of the robot, the coordinates of the path nodes being the pose in Cartesian space; The path nodes are smoothly fitted to obtain the planned path of the robot end in Cartesian space; under the kinematic constraints of the Cartesian space of the robot end, according to the planned path, velocity planning is used to obtain the robot end in Cartesian space. The planned trajectory of the Karl space, the speed of the planned trajectory is continuous in the Cartesian space; according to the planned trajectory of the robot end in the Cartesian space, the joint nodes of the robot end in the robot joint space are obtained, and the joint nodes are the robot end At the key points of the motion trajectory in its joint space, its coordinates are the coordinates of the robot's joint space; under the kinematic constraints of each axis of the robot, according to the joint nodes, the planned trajectory of the robot's end in its joint space is obtained, The velocity, acceleration and jerk of the planned trajectory are continuous.

The technical solution of this application uses Cartesian space path planning, Cartesian space trajectory planning and joint space trajectory planning to meet the requirements for the Cartesian space position, the requirements for Cartesian space motion and the robot joint space during the trajectory planning process of the robot end. The requirements of each axis motion are decoupled, which improves the position accuracy and smoothness of the final planned trajectory in Cartesian path planning. In Cartesian space trajectory planning, the final planned trajectory satisfies the motion speed constraints and continuity of Cartesian space. According to the requirements, the trajectory planning of the joint space realizes that the motion of each axis meets the constraints and continuity requirements of speed, acceleration and jerk, thereby improving the end trajectory motion performance of the robot.

The following describes a planning method embodiment, a device embodiment and other related embodiments of a robot end trajectory of the present application with reference to the accompanying drawings.

The following first introduces an embodiment of a planning method for the end trajectory of a robot with reference to Figures 1 to 2 of the accompanying drawings.

An embodiment of a planning method for the end trajectory of a robot performs smooth fitting on a pair of path nodes to obtain the planned path of the end of the robot in Cartesian space; under the kinematic constraints of the Cartesian space of the end of the robot, according to the planned path Use speed planning to obtain the planned trajectory of the robot end in Cartesian space; according to the planned trajectory of the robot end in Cartesian space, obtain the joint nodes of the robot end in the robot joint space; kinematic constraints on each axis of the robot Next, the planned trajectory of the robot end in its joint space is obtained based on the joint nodes.

Figure 1 shows the process of Embodiment 1 of a robot terminal trajectory planning method, including steps S110 to S150.

S110: Obtain several discrete path nodes at the end of the robot. The coordinates of the path nodes are the poses in Cartesian space.

Among them, the path nodes are key points in the movement process of the end of the multi-axis equipment, and are generally the results of CAD/CAM output.

Among them, Cartesian space includes Cartesian position space and Cartesian attitude space, and pose includes position and attitude. In some embodiments, attitude coordinates are represented by Euler angles. In other embodiments, the attitude coordinates are represented by continuous Euler angles.

Among them, continuous Euler angles have the same number of dimensions as Euler angles. In each dimension, the continuous Euler angle of a path node is equal to the continuous Euler angle of the previous path node and the Euler angle rotation angle of the node. And, the Euler angle rotation angle of a path node is equal to the forward rotation angle from the previous path node to the Euler angle of this path node.

S120: Perform smooth fitting on each path node to obtain the planned path of the Cartesian space at the end of the robot. The drawn path satisfies the smoothness and accuracy requirements of the position in Cartesian space.

Among them, the process of smooth fitting of path nodes includes one of the following: passing point method and non-passing point method.

Among them, the planned path after smooth fitting without point method may not necessarily pass through all path nodes, but the mean square error of the position deviation from each path node is less than the set threshold to meet the position accuracy requirements of the robot's motion trajectory in Cartesian space. , suitable for planning of regular paths. For example, a preferred implementation of the non-passing point method is to use line segments and arcs to smoothly fit path nodes.

Among them, the planned path smoothed by the point method passes through each path node, which meets the position accuracy requirements of the robot's motion trajectory in Cartesian space and is suitable for the planning of irregular paths. For example, a preferred implementation of the passing point method is to use polynomials or B-splines to smoothly fit discrete path nodes.

From the above, the pose of each path point obtained through path planning is a rasterization of the movement position of the end of the robot. It can be considered as a global planning of the movement position of the end of the robot, realizing the movement of the robot in Cartesian space. The trajectory meets the requirements of position smoothness and accuracy.

S130: Under the kinematic constraints of the Cartesian space of the robot end, use speed planning according to the planned path to obtain the planned trajectory of the robot end in Cartesian space.

Among them, the pose of each point on the planned trajectory in Cartesian space is the same as the pose of the corresponding path point on the planned path in Cartesian space in step S120. However, in this step, the pose and time of each path point are obtained through speed planning. relationship, that is, each path point adds a time attribute. For the sake of distinction, the planned path in the Cartesian space with the added time attribute is called the planned trajectory in the Cartesian space.

Among them, the kinematic constraints of the Cartesian space at the end of the robot are generally set according to the operating requirements of the end of the robot to meet the control purpose of the end of the robot.

In some embodiments, the Cartesian attitude space is represented by continuous Euler angles to solve the position discontinuity problem caused by the singular points of Euler angles. A possible implementation of this step includes:

1) Convert the posture of each path point in the planned path into the distance space coordinates. The distance space includes the distance length dimension on each coordinate axis of the Cartesian position space and the distance length dimension on each coordinate axis of the Descartes attitude space. A The path length of a path point on a coordinate axis in Cartesian space is the length of the planned path from the first path point to the path point projected on the coordinate axis.

For example, the Cartesian position space includes three axes: The position distance length dimension of , and the attitude distance length dimension on the three coordinate axes of θ, ψ and φ of the Cartesian attitude space.

2) Convert the kinematic constraints of the Cartesian space at the end of the robot into the kinematic constraints of the path space.

Among them, the Jacobian matrix can be used to convert the kinematic constraints of the Cartesian space at the end of the robot into the kinematic constraints of the path space.

3) Under the kinematic constraints of the distance space, use speed planning to obtain the planned trajectory of the robot end in the distance space according to the coordinates of the distance space, and the speed and coordinates of the robot end in the distance space are continuous.

Among them, the interpolation method of the speed planner is used to complete the planning trajectory of the robot end in the journey space, and in the process, the trajectories of each dimension of the journey space are kept synchronized.

4) Obtain the planned trajectory of the robot end in Cartesian space based on the planned trajectory of the journey space.

Among them, according to the movement trend of the path trajectory and the coordinates of each path point in the path space, the search method is used to convert the coordinates of each path point in the path space into the posture of each path point in the Cartesian space, forming a robot. The planned trajectory of the end in Cartesian space.

Among them, the speed of the robot's end in the path space is continuous, and the speed of the robot's end in Cartesian space is also continuous. The coordinates of the robot's end in the path space are continuous, and the position and posture of the robot's end in Cartesian space are also continuous.

In other embodiments, the posture space is also represented by continuous Euler angles, but is directly planned through the posture. This step adopts the following possible implementation methods, including:

Based on the kinematic constraints of the Cartesian space at the end of the robot, the position coordinates and attitude coordinates of each path point at the end of the robot are used to interpolate each path point at the end of the robot to obtain the planned trajectory of the robot end in Cartesian space. , and maintain the continuity of pose and velocity of each trajectory point of the planned trajectory.

In other embodiments, the attitude space is represented by Euler angles. A possible implementation of this step includes:

1) Convert the attitude coordinates of each path point at the end of the robot from Euler angles to quaternions.

Among them, the use of quaternions can solve the problem that Euler angles cannot be interpolated, but there is a problem of attitude discontinuity.

2) The kinematic constraints of the Cartesian space at the end of the robot, using the position coordinates of each path point at the end of the robot and the attitude coordinates represented by quaternions, interpolate each path point at the end of the robot to obtain the robot The planned trajectory of the end in Cartesian space, and the velocity of each trajectory point of the planned trajectory is maintained continuously.

From the above, through trajectory planning in Cartesian space, the speed of the robot's end in Cartesian space meets the speed control requirements of the robot's Cartesian space.

S140: According to the planned trajectory of the robot end in Cartesian space, obtain the joint nodes of the robot end in the robot's joint space. The joint nodes are the key points of the movement trajectory of the robot end in its joint space, and their coordinates are The coordinates of the joint space.

Among them, the planning trajectory of the joint space obtained in this step includes the joint trajectory, which is the relationship between the joint coordinates of the robot and time. On the basis of realizing the relationship between each point in Cartesian space and time in step S130, this step realizes the relationship between the position of each axis of the robot and time.

Among them, this step includes the following processes:

1) According to the planned trajectory of the robot end in Cartesian space, obtain the trajectory nodes of the robot end in Cartesian space. The trajectory nodes are the key points of the movement trajectory of the robot end in Cartesian space.

Among them, in some embodiments, according to the curvature of each point on the planned trajectory of the robot's end in Cartesian space, the trajectory node of the robot's end in Cartesian space is obtained, and the trajectory node determines the location of the robot's end in Cartesian space. The trend of the planned trajectory can smoothly fit the trajectory of the robot's end in Cartesian space.

2) The trajectory node is used as a joint node, and the inverse kinematics solution is used to convert the posture of the trajectory node into the coordinates of the joint node in the robot joint space.

Among them, the trajectory node is the key point of the movement trajectory of the robot end in Cartesian space, which can be used as the key point of the movement trajectory of the robot end in its joint space, that is, the joint node.

Among them, the methods of inverse kinematics solution include analytical method, numerical method and geometric method. This step does not limit the method of inverse kinematics solution.

From the above, the joint nodes of the robot end in the robot joint space are obtained through the inverse kinematics solution, which is used as the basis for trajectory planning in the robot joint space.

S150: Under the kinematic constraints of each axis of the robot, obtain the planned trajectory of the robot end in its joint space based on the coordinates of the joint nodes.

Among them, the planned trajectory of the robot end in its joint space includes the planned trajectory of each axis of the robot in the joint space, and the planned trajectories of each axis in the joint space are synchronized, that is, each axis reaches the position corresponding to each joint node synchronously.

This step includes the following processes:

1) Under the kinematic constraints of each axis of the robot, according to the coordinates of the joint nodes in the robot's joint space, use the interpolation method of the speed planner to plan the trajectory of each axis of the robot in its joint space. And based on this, the duration of each axis between adjacent joint nodes is obtained.

2) Obtain the synchronization duration of the robot between each pair of adjacent joint nodes based on the duration of each axis between each pair of adjacent joint nodes.

Among them, for a pair of adjacent joint nodes, the longest duration of each axis of the robot between the pair of adjacent joint nodes is regarded as the longest duration of each axis of the robot between the pair of adjacent joint nodes. The synchronization duration, that is, the movement duration of each axis of the robot between the pair of adjacent joint nodes is adjusted to the synchronization duration to optimize the robot's mobility.

3) According to the synchronization duration between each pair of adjacent joint nodes of the robot and the coordinates of the joint nodes in the robot joint space, speed planning is used to obtain each axis of the robot under the kinematic constraints of each axis of the robot. The secondary planned trajectory in its joint space is used as the planned trajectory of the robot end in its joint space.

From the above, the planned trajectories of each axis of the robot are synchronously planned under the kinematic constraints of each axis of the robot, which improves the robot's motion performance, and makes the speed, acceleration and jerk of the planned trajectory of each axis continuous, reducing the cause of each axis. The vibration caused by the jump of motion.

In summary, an embodiment of a planning method for the end trajectory of a robot performs smooth fitting on a pair of path nodes to obtain the planned path of the end of the robot in Cartesian space; under the kinematic constraints of the Cartesian space of the end of the robot, According to the planned path, speed planning is used to obtain the planned trajectory of the robot end in Cartesian space; according to the planned trajectory of the robot end in Cartesian space, the joint nodes of the robot end in the robot joint space are obtained; in the motion of each axis of the robot Under the scientific constraints, the planned trajectory of the robot end in its joint space is obtained according to the joint nodes. The technical solution of this embodiment uses Cartesian space path planning, Cartesian space trajectory planning and joint space trajectory planning to meet the requirements for Cartesian space position accuracy and kinematic constraints of Cartesian space motion during the trajectory planning process at the end of the robot. It is decoupled from the kinematic constraints of each axis of the robot and improves the position accuracy of the final planned trajectory in Cartesian path planning. Trajectory planning in Cartesian space makes the final planned trajectory satisfy the kinematic constraints of Cartesian space. Joint space trajectory planning enables the motion of each axis to meet kinematic constraints, thereby improving the robot's end trajectory motion performance.

Embodiment 2 of a planning method for the end trajectory of a robot uses continuous Euler angles to represent attitude coordinates; the path nodes are smoothly fitted by the passing point method to obtain the planned path of the end of the robot in Cartesian space; at the end of the robot Under the kinematic constraints of Cartesian space, the two-dimensional journey space coordinates are used to obtain the planned trajectory of the robot end in the journey space using speed planning, and converted into the planned trajectory of Cartesian space; under the kinematic constraints of each axis of the robot Next, the planned trajectory of the robot end in its joint space is obtained according to the joint nodes, and the jump points are smoothed and filtered.

Figure 2 shows the process of Embodiment 2 of a robot terminal trajectory planning method, including steps S210 to S250.

S210: Obtain several discrete path nodes at the end of the robot. The coordinates of the path nodes are the poses in Cartesian space, and their pose coordinates are represented by continuous Euler angles.

Among them, the path nodes are the key points in the movement process of the robot end, which are generally the results of CAD/CAM output.

Among them, the continuous Euler angle is used to represent the attitude, which facilitates the calculation of the coordinates of the attitude distance dimension in the subsequent journey planning space, thereby carrying out trajectory planning in the journey space and achieving attitude continuity, which solves the problem of singular points in Euler angles that cannot be interpolated. Also solves the problem of less continuous postures through quaternion interpolation.

S220: Use polynomials or B-splines to smoothly fit the path nodes to obtain the planned path of the robot end in Cartesian space.

Among them, polynomials or B-splines are used to smoothly fit the path nodes, and the smoothly fitted planned path passes through each path node.

From the above, using polynomials or B-splines to smoothly fit path nodes meets the smoothness and accuracy requirements of the planned path at the end of the robot.

S230: Convert the posture of each path point in the planned path into two-dimensional journey space coordinates, obtain the planned trajectory of the robot end in the journey space based on the journey space coordinates, and convert it into a planned trajectory in Cartesian space. The planned trajectory Velocity and pose are continuous in Cartesian space.

Among them, this step includes the following sub-steps:

1) Convert the posture of each path point in the planned path into the distance space coordinates. The distance space includes the position distance length dimension of the Cartesian position space and the attitude distance length dimension of the Cartesian attitude space.

Among them, the position path length of a path point is the length of the path from the first path point to this path point in the Cartesian position space, and the attitude path length of a path point is the distance from the first path point in the Cartesian attitude space. The length of the distance traveled from the waypoint to the waypoint.

2) Convert the kinematic constraints of the Cartesian space at the end of the robot into the kinematic constraints of the path space.

Among them, the kinematic constraints of the Cartesian space at the end of the robot are generally set according to the operating requirements of the end of the robot to meet the control purpose of the end of the robot.

Among them, the Jacobian matrix can be used to convert the kinematic constraints of the Cartesian space at the end of the robot into the kinematic constraints of the path space.

3) Under the kinematic constraints of the distance space, use speed planning to obtain the planned trajectory of the robot end in the distance space according to the coordinates of the distance space, and the speed and coordinates of the robot end in the distance space are continuous.

Among them, the interpolation method of the speed planner is used to complete the planning trajectory of the robot end in the journey space, and in the process, the trajectories of each dimension of the journey space are kept synchronized. Because in this embodiment, as long as the two dimensions of the route space need to be synchronized, the planning accuracy is high.

4) Obtain the planned trajectory of the robot end in Cartesian space based on the planned trajectory of the journey space.

Among them, according to the movement trend of the path trajectory and the coordinates of each path point in the path space, the search method is used to convert the coordinates of each path point in the path space into the posture of each path point in the Cartesian space, forming a robot. The planned trajectory of the end in Cartesian space.

From the above, the speed of the end of the robot in the path space is continuous, and the speed of the end of the robot in the Cartesian space is also continuously. The position and posture dimensions of the robot's end in the path space are both continuous, and the position and posture of the robot's end in Cartesian space are also continuous. Moreover, the two-dimensional journey space is used for planning, and the planning accuracy is high.

S240: According to the planned trajectory of the robot end in Cartesian space, obtain the joint nodes of the robot end in the robot joint space. The joint nodes are the key points of the movement trajectory of the robot end in its joint space, and their coordinates are the robot joints. The coordinates of space.

Among them, this step is the same as step S140 of Embodiment 1 of the robot terminal trajectory planning method, and will not be described in detail here.

S250: Under the kinematic constraints of each axis of the robot, first obtain the time synchronization between adjacent nodes according to the joint nodes, and then obtain the planned trajectory of the robot end in its joint space through speed planning, and filter the planned trajectory, and finally The planned trajectory speed, acceleration and jerk are continuous.

Among them, the planned trajectory of the robot end in its joint space includes the planned trajectory of each axis of the robot in the joint space, and the planned trajectories of each axis in the joint space are synchronized, that is, each axis reaches the position corresponding to each joint node synchronously.

Among them, the kinematic constraints of each axis of the robot are obtained based on the dynamics constraints of each axis of the robot, so that the planned trajectory of each axis of the robot conforms to the dynamics constraints, and each axis of the robot can be planned according to the corresponding The track can be run.

Among them, this step is completed through the speed planner. The relationship between position and time in the speed planner is an analytical formula with cosine as the kernel function. The speed planner uses an S-shaped curve to predict the speed during interpolation.

This step includes the following processes:

1) According to the coordinates of the joint nodes in the robot joint space, obtain the inflection points of each axis of the robot.

Among them, the speed of an axis of a robot at the inflection point of the axis is 0.

2) Under the kinematic constraints of each axis of the robot, according to the coordinates of the inflection points of each axis of the robot in the robot joint space, use the interpolation method of the speed planner to calculate the trajectory of each axis of the robot in its joint space. Carry out a planning and obtain the duration between each adjacent joint node of each axis of the robot.

3) Obtain the synchronization duration of the robot between each pair of adjacent joint nodes based on the duration of each axis of the robot between each pair of adjacent joint nodes.

Wherein, for a pair of adjacent joint nodes, the longest time period between each axis of the robot between the pair of adjacent joint nodes is regarded as the longest time period between the pair of adjacent joint nodes. The synchronization duration between them, that is, the movement duration of each axis of the robot between the pair of adjacent joint nodes is adjusted to the synchronization duration.

4) According to the synchronization duration between each pair of adjacent joint nodes of the robot and the coordinates of the joint nodes in the robot's joint space, and under the kinematic constraints of each axis of the robot, speed planning is used to obtain each of the robot's The quadratic planning trajectory of the axis in its joint space.

5) When there is a jump in speed, acceleration or jerk in the quadratic planning trajectory of an axis of the robot, the jump is made continuous through balance filtering, and the quadratic planning trajectory of the axis is adjusted as the axis The final planned trajectory in the robot joint space.

From the above, by adding jump point filtering to the quadratic planned trajectory, the continuity of speed, acceleration and jerk on the planned trajectory of each axis of the robot is further improved.

In summary, the second embodiment of a planning method for a robot's end trajectory not only decouples the requirements of Cartesian space position, Cartesian space motion and the motion of each axis of the robot's joint space, so that the final planning The drawing trajectory meets the requirements of Cartesian space position, Cartesian space motion requirements and the requirements of each axis motion of the robot joint space. At the same time, it simplifies the synchronization problem of the planned trajectory in the Cartesian space and makes the posture of the planned trajectory in the Cartesian space Continuous and eliminates the motion jump points of the trajectory in the joint space, further improving the robot's motion performance and further reducing the vibrations caused by the motion jumps of each axis.

The following describes an embodiment of a planning device for a robot end trajectory with reference to Figures 3 and 4.

Embodiment 1 of a planning device for the end trajectory of a robot executes the method described in Embodiment 1 of a planning method for the end trajectory of a robot. Figure 3 shows the structure of Embodiment 1 of a planning device for the end trajectory of a robot. It includes: node acquisition module 310, path smoothing module 320, Cartesian trajectory planning module 330, inverse kinematics solution module 340 and joint trajectory planning module 350.

The node acquisition module 310 is used to acquire several discrete path nodes at the end of the robot. The coordinates of the path nodes are the poses of the Cartesian space. For its working principle and advantages, please refer to step S110 in Embodiment 1 of a robot terminal trajectory planning method.

The path smoothing module 320 is used to perform smooth fitting on each path node to obtain the planned path of the robot end in Cartesian space. For its working principle and advantages, please refer to step S120 in Embodiment 1 of a robot terminal trajectory planning method.

The Cartesian trajectory planning module 330 is used to obtain the planned trajectory of the robot end in the Cartesian space by using speed planning according to the planned path under the kinematic constraints of the Cartesian space of the robot end. For its working principle and advantages, please refer to step S130 in Embodiment 1 of a robot terminal trajectory planning method.

The inverse kinematics module 340 is used to obtain the joint nodes of the robot end in the robot's joint space based on the planned trajectory of the robot's end in Cartesian space. The joint nodes are the key points of the motion trajectory of the robot's end in its joint space. Its coordinates are the coordinates of the robot's joint space. For its working principle and advantages, please refer to step S140 in Embodiment 1 of a robot terminal trajectory planning method.

The joint trajectory planning module 350 is used to obtain the planned trajectory of the robot end in its joint space based on the joint nodes under the kinematic constraints of each axis of the robot. For its working principle and advantages, please refer to step S150 in Embodiment 1 of a robot terminal trajectory planning method.

Embodiment 2 of a planning device for a robot's end trajectory executes the method described in Embodiment 2 of a planning method for a robot's end trajectory. Figure 4 shows the structure of Embodiment 2 of a planning device for a robot's end trajectory. It includes: node acquisition module 410, path smoothing module 420, Cartesian trajectory planning module 430, inverse kinematics solution module 440 and joint trajectory planning module 450.

The node acquisition module 410 is used to acquire several discrete path nodes at the end of the robot. The coordinates of the path nodes are poses in Cartesian space, and the pose coordinates are represented by continuous Euler angles. For its working principle and advantages, please refer to step S210 in Embodiment 2 of a robot terminal trajectory planning method.

The path smoothing module 420 is used to perform smooth fitting on each path node using polynomials or B-splines to obtain the planned path of the robot end in Cartesian space. For its working principle and advantages, please refer to step S220 in Embodiment 2 of a robot terminal trajectory planning method.

The Cartesian trajectory planning module 430 is used to convert the posture of each path point in the planned path into two-dimensional journey space coordinates, obtain the planned trajectory of the robot end in the journey space according to the journey space coordinates, and convert it into Cartesian trajectory planning module 430. The planning trajectory of the Karl space, the speed and posture of the planning trajectory in the Cartesian space are continuous. For its working principle and advantages, please refer to step S230 in Embodiment 2 of a robot terminal trajectory planning method.

The inverse kinematics module 440 is used to obtain the joint nodes of the robot end in the robot's joint space based on the planned trajectory of the robot's end in Cartesian space. The joint nodes are the key to the movement trajectory of the robot's end in its joint space. Point, its coordinates are the coordinates of the robot joint space. For its working principle and advantages, please refer to step S240 in Embodiment 2 of a robot terminal trajectory planning method.

The joint trajectory planning module 450 is used to obtain the time synchronization between adjacent nodes according to the joint nodes under the kinematic constraints of each axis of the robot, and then obtain the planned trajectory of the robot end in its joint space through speed planning, and calculate the plan The trajectory is filtered, and the final planned trajectory velocity, acceleration and jerk are continuous. For its working principle and advantages, please refer to step S250 in Embodiment 2 of a robot terminal trajectory planning method.

An embodiment of the present application also provides a computing device, which is described in detail below with reference to Figure 5 .

The computing device 500 includes a processor 510, a memory 520, a communication interface 530, and a bus 540.

It should be understood that the communication interface 530 in the computing device 500 shown in this figure can be used to communicate with other devices.

The processor 510 can be connected to the memory 520 . The memory 520 may be used to store the program code and data. Therefore, the memory 520 may be a storage unit internal to the processor 510 , or may be an external storage unit independent of the processor 510 , or may include a storage unit internal to the processor 510 and an external storage unit independent of the processor 510 . part.

Optionally, the computing device 500 may also include a bus 540. Among them, the memory 520 and the communication interface 530 can be connected to the processor 510 through the bus 540. The bus 540 may be a Peripheral Component Interconnect (PCI) bus or an Extended Industrial Standard Architecture (EFStended Industry Standard Architecture, EISA) bus, etc. The bus 540 can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, only one line is used in this figure, but it does not mean that there is only one bus or one type of bus.

It should be understood that in this embodiment of the present application, the processor 510 may be a central processing unit (CPU). The processor can also be other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), off-the-shelf programmable gate arrays (field programmable gate arrays, FPGAs) or other Programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or the processor may be any conventional processor, etc. Or the processor 510 uses one or more integrated circuits to execute relevant programs to implement the technical solutions provided by the embodiments of this application.

The memory 520 may include read-only memory and random access memory and provides instructions and data to the processor 510 . A portion of processor 510 may also include non-volatile random access memory. For example, processor 510 may also store device type information.

When the computing device 500 is running, the processor 510 executes the computer execution instructions in the memory 520 to perform the operation steps of each method embodiment.

It should be understood that the computing device 500 according to the embodiments of the present application may correspond to the corresponding subjects in performing the methods according to the various embodiments of the present application, and the above and other operations and/or functions of the respective modules in the computing device 500 In order to implement the corresponding processes of each method in this method embodiment, for the sake of simplicity, they will not be described again here.

Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented with electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Skilled artisans may implement the described functionality using different methods for each specific application, but such implementations should not be considered beyond the scope of this application.

Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the systems, devices and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be described again here.

In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components may be combined or can be integrated into another system, or some features can be ignored, or not implemented. On the other hand, the coupling or direct coupling or communication connection between each other shown or discussed may be through some interfaces, and the indirect coupling or communication connection of the devices or units may be in electrical, mechanical or other forms.

The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place, or they may be distributed to multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the method embodiment.

In addition, each functional unit in each embodiment of the present application can be integrated into one processing unit, each unit can exist physically alone, or two or more units can be integrated into one unit.

If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the existing technology or the part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including Several instructions are used to cause a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the decoding method described in various embodiments of this application. The aforementioned storage media include U disk, mobile hard disk, Read-Only Memory (ROM), Random Access Memory (RAM), magnetic disk or optical disk and other media that can store program code. .

Embodiments of the present application also provide a computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, the program is used to perform the operating steps of each method embodiment.

The computer storage medium in the embodiment of the present application may be any combination of one or more computer-readable media. The computer-readable medium may be a computer-readable signal medium or a computer-readable storage medium. The computer-readable storage medium may be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or device, or any combination thereof. More specific examples (non-exhaustive list) of computer readable storage media include electrical connections having one or more conductors, portable computer disks, hard drives, random access memory (RAM), read only memory (ROM), Erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination of the above. In this document, a computer-readable storage medium may be any tangible medium that contains or stores a program, The program may be used by or in conjunction with an instruction execution system, apparatus, or device.

A computer-readable signal medium may include a data signal propagated in baseband or as part of a carrier wave carrying computer-readable program code therein. Such propagated data signals may take many forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. A computer-readable signal medium may also be any computer-readable medium other than a computer-readable storage medium that can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device .

Program code embodied on a computer-readable medium may be transmitted using any suitable medium, including, but not limited to, wireless, wire, optical cable, RF, etc., or any suitable combination of the foregoing.

Computer program code for performing the operations of the present application may be written in one or more programming languages, including object-oriented programming languages such as Java, Smalltalk, C++, and conventional Procedural programming language—such as "C" or a similar programming language. The program code may execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In situations involving remote computers, the remote computer can be connected to the user's computer through any kind of network, including a local area network (LAN) or a wide area network (WAN), or it can be connected to an external computer (such as an Internet service provider through the Internet). connect).

Note that the above are only the preferred embodiments of the present application and the technical principles used. Those skilled in the art will understand that the present application is not limited to the specific embodiments described here, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of the present application. Therefore, although the present application has been described in detail through the above embodiments, the present application is not limited to the above embodiments. Without departing from the concept of the present application, it can also include more other equivalent embodiments, all of which belong to the present application. Apply for protection scope.

Claims (10)

A planning method for the terminal trajectory of a robot, which is characterized by including: Obtain several discrete path nodes at the end of the robot, and the coordinates of the path nodes are the poses in Cartesian space; Perform smooth fitting on the path nodes to obtain the planned path of the robot end in Cartesian space; Under the speed constraints of the Cartesian space of the robot end, obtain the planned trajectory of the robot end in the Cartesian space through speed planning according to the planned path; According to the planned trajectory of the robot end in Cartesian space, the joint nodes of the robot end in the robot joint space are obtained. The joint nodes are the key points of the movement trajectory of the robot end in the joint space, and their coordinates are in the robot joint space. coordinate of; Under the kinematic constraints of each axis of the robot, the planned trajectory of the robot end in its joint space is obtained according to the joint nodes. The method according to claim 1, characterized in that the posture in the posture is represented by a continuous Euler angle, and the continuous Euler angle of a path node is equal to the continuous Euler angle of the previous path node and the continuous Euler angle of the path node. The sum of Euler angle rotation angles of a node. The Euler angle rotation angle of a path node is equal to the forward rotation angle from the previous path node to the Euler angle of the path node. The method according to claim 1 or 2, characterized in that the process of smooth fitting the path nodes includes one of the following: Smoothly fit the path nodes using line segments and arcs; Use polynomials or B-splines to smoothly fit the path nodes. The method according to claim 2, characterized in that, under the kinematic constraints of the Cartesian space of the robot end, using speed planning according to the planned path to obtain the planned trajectory of the robot end in the Cartesian space, including : According to the posture of each path point of the planned path, the position path length and the angular path length of each path point are obtained. The position path length and the angular path length form the coordinates of the path space, and a path The positional path length of a point is the length of the planned path from the first path point to this path point in Cartesian position space, and the angular path length of a path point is the length of the planned path from the first path point in Cartesian attitude space. The length of the planned path from a path point to the path point; Convert the kinematic constraints of the Cartesian space at the end of the robot into the kinematic constraints of the path space; Under the kinematic constraints of the distance space, use speed planning to obtain the planned trajectory of the robot end in the distance space according to the coordinates of the distance space, and the speed of the robot end in the distance space is continuous; The planned trajectory of the robot end in Cartesian space is obtained according to the planned trajectory of the journey space. The method according to claim 2, characterized in that, under the kinematic constraints of the Cartesian space of the robot end, using speed planning according to the planned path to obtain the planned trajectory of the robot end in the Cartesian space, including : According to the pose of each path point of the planned path, the path length of each path point on each coordinate axis of the Cartesian position space is obtained, and the coordinates of the path space of the planned path are formed, a path point at The length of the journey on a coordinate axis of Cartesian space is the length of the planned path from the first path point to the path point projected on the coordinate axis; Convert the kinematic constraints of the Cartesian space at the end of the robot into the kinematic constraints of the path space; Under the kinematic constraints of the distance space, use speed planning to obtain the planned trajectory of the robot end in the distance space according to the coordinates of the distance space, and the speed of the robot end in the distance space is continuous; The planned trajectory of the robot end in Cartesian space is obtained according to the planned trajectory of the journey space. The method according to claim 1 or 2, characterized in that, according to the planned trajectory of the robot end in Cartesian space, obtaining the joint nodes of the robot end in the robot joint space includes: According to the planned trajectory of the robot end in Cartesian space, obtain the trajectory nodes of the robot end in Cartesian space. The trajectory nodes are the key points of the movement trajectory of the robot end in Cartesian space; Taking the trajectory node as the joint node, the inverse kinematics solution is used to convert the pose of the trajectory node into the coordinates of the joint node in the robot joint space. The method according to claim 1 or 2, characterized in that, under the kinematic constraints of each axis of the robot, obtaining the planned trajectory of the robot end in its joint space according to the joint nodes includes: Under the kinematic constraints of each axis of the robot, velocity planning is used to obtain a planned trajectory of each axis of the robot in the joint space according to the coordinates of the joint nodes in the joint space of the robot, and accordingly the trajectory of the robot is obtained. The duration of movement of each axis between adjacent joint nodes; For any pair of adjacent joint nodes, the longest time of the movement duration of each axis of the robot between the pair of adjacent joint nodes is regarded as the synchronization duration between the pair of adjacent joint nodes; According to the synchronization duration between each pair of adjacent joint nodes of the robot and the coordinates of the joint nodes in the robot's joint space, speed planning is used to obtain each axis of the robot under the kinematic constraints of each axis of the robot. The secondary planned trajectory in the joint space is used as the planned trajectory of the robot end in its joint space. In this planned trajectory, the speed, acceleration and jerk of each axis of the robot are continuous. A planning device for the terminal trajectory of a robot, which is characterized by including: The node acquisition module is used to acquire several discrete path nodes at the end of the robot. The coordinates of the path nodes are the poses in Cartesian space; The path smoothing module is used to perform smooth fitting on the path nodes to obtain the planned path of the robot end in Cartesian space; The Cartesian trajectory planning module is used to obtain the planned trajectory of the robot end in Cartesian space by using speed planning according to the planned path under the kinematic constraints of the Cartesian space at the end of the robot; The inverse kinematics solution module is used to obtain the joint nodes of the robot end in the robot joint space based on the planned trajectory of the robot end in Cartesian space. The joint nodes are the key to the motion trajectory of the robot end in its joint space. Point, its coordinates are the coordinates of the robot joint space; The joint trajectory planning module is used to obtain the planned trajectory of the robot end in the joint space based on the joint nodes under the kinematic constraints of each axis of the robot. A computing device, characterized by including: bus; A communication interface connected to the bus; at least one processor connected to the bus; and At least one memory is connected to the bus and stores program instructions, which when executed by the at least one processor cause the at least one processor to perform the method of any one of claims 1 to 7. A computer-readable storage medium on which program instructions are stored, characterized in that, when executed by a computer, the program instructions cause the computer to execute the method of any one of claims 1 to 7.