Mechanical arm track smooth transition method and system and readable storage medium

Abstract

The invention discloses a mechanical arm track smooth transition method and system and a readable storage medium. The method comprises the steps that a transition starting point and a transition ending point are calculated; calculating a Bell curve parameter track and a Bell curve arc length of a transition section; calculating a transition speed according to the constraint condition, and finishing transition of adjacent tracks based on the transition speed; if the current track is the last transition connection section, S-shaped acceleration and deceleration interpolation motion is carried out, and smooth transition of all tracks is completed. According to the method, a quintic Bezier curve is adopted between every two adjacent track sections to solve the smooth transition track at the joint corner, smooth transition at the joint of multiple track sections can be achieved by solving the optimal speed at the joint, the smoothness and continuity of the movement speed are guaranteed, and the operation efficiency of an end effector is effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of robot control and data processing, and more specifically, to a method, system and readable storage medium for smooth transition of robot arm trajectories. Background Art

[0002] Industrial robots are multi-joint manipulators or multi-degree-of-freedom machine devices widely used in the industrial field. They have a certain degree of automation and can rely on their own power and control capabilities to achieve various industrial processing and manufacturing functions.

[0003] At present, due to the sharp transition corners at the connection of multiple trajectory segments of industrial robots, the acceleration and deceleration control method with zero initial and final speeds is adopted when interpolating discrete small line segments. However, this method will cause continuous mutations in the speed direction during the entire interpolation process, that is, the frequent start and stop of the drive axis will affect the accuracy of motion positioning. Therefore, how to perform motion control at high speed and smoothly is a practical problem that must be solved. Summary of the invention

[0004] The purpose of the present invention is to provide a method, system and readable storage medium for smooth transition of a robot arm trajectory, which uses a quintic Bezier curve between adjacent trajectory segments to smoothly transition at the connecting corners and achieve the optimal speed at the connecting circle, so as to achieve a smooth transition at the connection of multiple trajectory segments, ensure the smoothness and continuity of the movement speed, and effectively improve the operating efficiency of the end effector.

[0005] A first aspect of the present invention provides a method for smooth transition of a robot arm trajectory, comprising the following steps: Calculate the transition start point and transition end point; Calculate the parameter trajectory of the transition section Belset curve and the arc length of the Belset curve; Calculate the transition speed according to the constraint conditions, and complete the transition of adjacent trajectories based on the transition speed; If the current trajectory is the last transition segment, an S-shaped acceleration and deceleration interpolation motion is performed to complete the smooth transition of the current trajectory.

[0006] In this solution, the calculation of the transition starting point includes: According to Length of segment position track and the actual transition radius Find the The parameter value corresponding to the transition starting point of the segment position trajectory transition segment ; According to The parameter expression of the position trajectory of the segment is obtained. The transition starting point of the segment position trajectory transition segment, including the transition starting point of the calculated straight line trajectory and the transition starting point of the calculated arc trajectory.

[0007] In this scheme, the transition end point is calculated, specifically including: According to +1 length of position track and the actual transition radius Find the The parameter value corresponding to the transition end point of the segment position trajectory transition segment : According to The parameter expression of the segment position trajectory is obtained The transition end point of the segment position trajectory transition segment, including the transition end point of the calculated straight line trajectory and the transition end point of the calculated arc trajectory.

[0008] In this scheme, the parameter trajectory of the transition section Belset curve is calculated, which specifically includes: Reparameterization calculation parameters based on Newton's method ; According to the parameters Calculate the control points on the Bezier curve corresponding to the arc length, wherein the control points of the quintic Bezier curve include , , , , and There are six points in total; The transition segment parameter trajectory of the quintic Bezier curve is calculated based on the control points.

[0009] In this solution, the arc length of the Belset curve is calculated, which specifically includes: Calculate the arc length of the Bezier curve, set , use the sum of the distances between discrete points in the interval to approximate the length and get the approximate length : ; in, It is the unit of counting for cumulative calculation, and the approximate length is approximated according to the mean value theorem. Get the middle value : ; Among them, when When , the length of the Bezier curve is obtained: ; in, is the parameter trajectory of the transition section Belset curve, The derivative of .

[0010] In this solution, the transition speed is calculated according to the constraint conditions, and the transition of adjacent trajectories is completed based on the transition speed, which specifically includes: Extract length value As the constraint condition, the minimum transition speed of adjacent line segments is obtained as ; Obtaining a Bezier curve transition segment based on the six control points, and calculating a transition speed of each segment based on endpoints on both sides of the transition segment of each segment; The transition between adjacent trajectories is completed based on the corresponding transition speed of each segment.

[0011] The second aspect of the present invention further provides a robot arm trajectory smooth transition system, comprising a memory and a processor, wherein the memory comprises a robot arm trajectory smooth transition method program, and when the robot arm trajectory smooth transition method program is executed by the processor, the following steps are implemented: Calculate the transition start point and transition end point; Calculate the parameter trajectory of the transition section Belset curve and the arc length of the Belset curve; Calculate the transition speed according to the constraint conditions, and complete the transition of adjacent trajectories based on the transition speed; If the current trajectory is the last transition segment, an S-shaped acceleration and deceleration interpolation motion is performed to complete the smooth transition of the current trajectory.

[0012] In this solution, the calculation of the transition starting point includes: According to Length of segment position track and the actual transition radius Find the The parameter value corresponding to the transition starting point of the segment position trajectory transition segment ; According to The parameter expression of the position trajectory of the segment is obtained. The transition starting point of the segment position trajectory transition segment, including the transition starting point of the calculated straight line trajectory and the transition starting point of the calculated arc trajectory.

[0013] In this scheme, the transition end point is calculated, specifically including: According to +1 length of position track and the actual transition radius Find the The parameter value corresponding to the transition end point of the segment position trajectory transition segment : According to The parameter expression of the position trajectory of the segment is obtained. The transition end point of the segment position trajectory transition segment, including the transition end point of the calculated straight line trajectory and the transition end point of the calculated arc trajectory.

[0014] In this scheme, the parameter trajectory of the transition section Belset curve is calculated, which specifically includes: Reparameterization calculation parameters based on Newton's method ; According to the parameters Calculate the control point on the Bezier curve corresponding to the arc length, wherein the control end includes , , , , and ; The transition segment parameter trajectory of the quintic Bezier curve is calculated based on the control points.

[0015] In this solution, the arc length of the Belset curve is calculated, which specifically includes: Calculate the arc length of the Bezier curve, set , use the sum of the distances between discrete points in the interval to approximate the length and get the approximate length : ; in, It is the unit of counting for cumulative calculation, and the approximate length is approximated according to the mean value theorem. Get the middle value : ; Among them, when When , the length of the Bezier curve is obtained: ; in, is the parameter trajectory of the transition section Belset curve, The derivative of .

[0016] In this solution, the transition speed is calculated according to the constraint conditions, and the transition of adjacent trajectories is completed based on the transition speed, which specifically includes: Extract length value As the constraint condition, the minimum transition speed of adjacent line segments is obtained as ; Based on the six control points, five transition segments are obtained, and based on the endpoints on both sides of the transition segment of each segment, the transition speed of each segment is calculated; The transition between adjacent trajectories is completed based on the corresponding transition speed of each segment.

[0017] The third aspect of the present invention provides a computer-readable storage medium, which includes a robot arm trajectory smooth transition method program for a machine. When the robot arm trajectory smooth transition method program is executed by a processor, the steps of a robot arm trajectory smooth transition method as described in any one of the above items are implemented.

[0018] The present invention discloses a method, system and readable storage medium for smooth transition of a robot arm trajectory, which adopts a quintic Bezier curve to smoothly transition the connecting corners between adjacent trajectory segments and achieve the optimal speed at the connecting circle, so as to achieve a smooth transition at the connection of multiple trajectory segments, ensure the smoothness and continuity of the movement speed, and effectively improve the operating efficiency of the end effector. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A schematic diagram showing the steps of a method for smooth transition of a robot arm trajectory according to the present invention is shown; Figure 2 A flow chart of a method for smooth transition of a robot arm trajectory according to the present invention is shown; Figure 3 A block diagram of a robot arm trajectory smooth transition system of the present invention is shown. DETAILED DESCRIPTION

[0020] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0021] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0022] In order to solve the problem of high-speed and smooth motion control, speed control of the terminal is the core technology, so the acceleration and deceleration control algorithm is the basis of the entire motion control algorithm, speed look-ahead control is the compensation technology to ensure the real-time performance of motion control, the smooth transition algorithm between adjacent straight line segments is the guarantee of the efficiency of speed planning, and the interpolation algorithm is the way for the terminal to achieve the ideal trajectory. Among them, this application is based on the S-shaped acceleration and deceleration speed planning algorithm and the speed look-ahead algorithm to calculate the optimal speed of the transition point. Under the given transition point, a quintic Bezier curve is constructed to achieve a smooth transition of the corners between line segments, ensuring the smoothness and continuity of the motion speed, and effectively improving the operating efficiency of the end effector; the Newton method is used to calculate the parameters of the Bezier curve to meet the end interpolation accuracy.

[0023] Specifically, Figure 1A flow chart of a method for smooth transition of a robot arm trajectory of the present application is shown.

[0024] like Figure 1 As shown, the present application discloses a method for smooth transition of a robot arm trajectory, comprising the following steps: S102, calculating a transition start point and a transition end point; S104, calculating the parameter trajectory of the transition section Belset curve and the arc length of the Belset curve; S106, calculating a transition speed according to the constraint conditions, and completing the transition of adjacent trajectories based on the transition speed; S108, if the current trajectory is the last transition segment, then an S-shaped acceleration / deceleration interpolation motion is performed to complete the smooth transition of the current trajectory.

[0025] It should be noted that, in this embodiment, Figure 2 As shown, it is a flow chart of the robot arm trajectory smooth transition method. The transition radius, transition starting point and transition end point are calculated according to the total number of input points, the speed and acceleration of each trajectory segment, and then the transition segment Belset curve parameter trajectory and the Belset curve arc length are calculated. Then the transition speed is calculated according to the constraint conditions, and the transition of adjacent trajectories is completed based on the transition speed. Among them, if the current trajectory is the last transition connection segment, the current trajectory is smoothly transitioned after S-shaped acceleration and deceleration interpolation motion.

[0026] According to an embodiment of the present invention, calculating the transition starting point specifically includes: According to Length of segment position track and the actual transition radius Find the The parameter value corresponding to the transition starting point of the segment position trajectory transition segment ; According to The parameter expression of the segment position trajectory is obtained The transition starting point of the segment position trajectory transition segment, including the transition starting point of the calculated straight line trajectory and the transition starting point of the calculated arc trajectory.

[0027] It should be noted that, in this embodiment, according to Length of segment position track and the actual transition radius Find the The parameter value corresponding to the transition starting point of the segment position trajectory transition segment : , According to the Parametric expressions for segment position trajectories , find the Segment position The transition starting point of the trajectory transition segment, where: Transition start point for straight line trajectory: ; Transition starting point of arc trajectory: .

[0028] It is The starting point of the segment position trajectory, It is The end point of the position trajectory is also the The starting point of the segment position trajectory, For the End point of the segment position trajectory.

[0029] According to an embodiment of the present invention, calculating the transition endpoint specifically includes: According to +1 length of position track and the actual transition radius Find the The parameter value corresponding to the transition end point of the segment position trajectory transition segment : According to The parameter expression of the segment position trajectory is obtained The transition end point of the segment position trajectory transition segment, which includes calculating the transition end point straight line trajectory and calculating the transition end point arc trajectory.

[0030] It should be noted that, in this embodiment, according to +1 length of position track and the actual transition radius Find the The parameter value corresponding to the transition starting point of the segment position trajectory transition segment : According to the Parameter expressions for segment position trajectories , find the Segment position trajectory transition end point of the transition segment, where, Transition end point of a straight line trajectory: ; Arc trajectory transition end point: .

[0031] in, For the The radius of the circle on which the segment arc trajectory lies, For the The center angle of the arc segment trajectory, is the transition parameter of the segment trajectory.

[0032] According to an embodiment of the present invention, calculating the parameter trajectory of the transition section Beerset curve specifically includes: Reparameterization calculation parameters based on Newton's method ; According to the parameters Calculate the control point on the Bezier curve corresponding to the arc length, wherein the control end includes , , , , and ; The transition segment parameter trajectory of the quintic Bezier curve is calculated based on the control points.

[0033] It should be noted that in this embodiment, to obtain the parameter position of a certain arc length, the brute force method only requires traversing the integral interval once. , stop when you are close enough to the target arc length value. The brute force method requires a smaller granularity If the arc length of the Bezier curve is very long, many queries are required, which will consume a lot of time. The next section will explain how to use Newton's method to find , we will look for The problem is modeled as: , Representation parameters The arc length of the curve position corresponding to the position from its starting point, , is the expected arc length. In order to use Newton's method to obtain the parameters , respectively, The first and second derivatives of : ; ; ; Finally, the parameters The calculation formula is as follows: ; Furthermore, according to the parameters Calculate the control point on the Bezier curve corresponding to the arc length, wherein the control end includes , , , , and ,in, The total number of control points of the Bezier curve is , the parameter expression is as follows: ; ; For the six control points, , , its first-order derivative and second-order derivative are: , ; , , the remaining four control points can be obtained by its derivative: ; ; ; ; But the parameters cannot be analyzed directly and It is difficult to summarize useful rules to simplify parameters to see how different values ​​will affect the transition effect of the position trajectory transition segment. and Therefore, the parameter is introduced Replacement parameters and ,parameter With parameters and The calculation is shown in the formula: .

[0034] According to an embodiment of the present invention, calculating the arc length of a Beerset curve specifically includes: Calculate the arc length of the Bezier curve, set , use the sum of the distances between discrete points in the interval to approximate the length and get the approximate length : ; in, It is the unit of counting for cumulative calculation, and the approximate length is approximated according to the mean value theorem. Get the middle value : ; Among them, when When , the length of the Bezier curve is obtained: ; in, is the parameter trajectory of the transition section Belset curve, The derivative of .

[0035] It should be noted that, in this embodiment, in order to calculate the point on the Bezier curve corresponding to the specified arc length, the arc length of the Bezier curve is first obtained, and the setting , use the sum of the distances between discrete points in the interval to approximate the length and get the approximate length :

[0036] The approximate length is approximated by the mean value theorem Get the middle value : ; Among them, when When , the length of the Bezier curve is obtained: ; therefore, Bezier curve of The calculation formula of the derivative is as follows: ; .

[0037] According to an embodiment of the present invention, calculating the transition speed according to the constraint condition and completing the transition of adjacent trajectories based on the transition speed specifically includes: Extract length value As the constraint condition, the minimum transition speed of adjacent line segments is obtained as ; Obtaining a Bezier curve transition segment based on the six control points, and calculating a transition speed of each segment based on endpoints on both sides of the transition segment of each segment; The transition between adjacent trajectories is completed based on the corresponding transition speed of each segment.

[0038] It should be noted that, in this embodiment, the line segments in adjacent trajectory segments are connected by the asymmetric S-shaped acceleration and deceleration control method. and Acceleration and deceleration planning is performed, and the quintic Bezier curve of the connecting section is processed at a uniform speed. In order to make the end effector run efficiently, the speed of the transition section is planned to be the minimum speed that can be achieved by the adjacent line segments. The details are as follows: End from point Movement to point When the system uses acceleration and deceleration control to make the terminal speed change from the initial speed to Accelerate and decelerate to the transition point , is the maximum acceleration allowed by the system, then the length of the line segment is The transition speed under the constraint of for: , Similarly, the end point Movement to point When the length of the line segment is The transition speed under the constraint of for: , In addition, the velocity of the end under the constraints of the arc length and interpolation period of the Bezier curve is: , Finally, the transition speed of the transition point at the end is obtained: .

[0039] Figure 3 A block diagram of a robot arm trajectory smooth transition system of the present invention is shown.

[0040] like Figure 3 As shown, the present invention discloses a robot arm trajectory smooth transition system, including a memory and a processor, wherein the memory includes a robot arm trajectory smooth transition method program, and when the robot arm trajectory smooth transition method program is executed by the processor, the following steps are implemented: Calculate the transition start point and transition end point; Calculate the parameter trajectory of the transition section Belset curve and the arc length of the Belset curve; Calculate the transition speed according to the constraint conditions, and complete the transition of adjacent trajectories based on the transition speed; If the current trajectory is the last segment, S-shaped acceleration and deceleration interpolation is performed to interpolate each segment of the trajectory and complete the smooth transition of the trajectory.

[0041] It should be noted that, in this embodiment, Figure 2 As shown, it is a flow chart of the robot arm trajectory smooth transition method. The transition radius, transition starting point and transition end point are calculated according to the total number of input points, the speed and acceleration of each trajectory segment, and then the transition segment Belset curve parameter trajectory and the Belset curve arc length are calculated. Then the transition speed is calculated according to the constraint conditions, and the transition of adjacent trajectories is completed based on the transition speed. Among them, if the current trajectory is the last transition connection segment, the current trajectory is smoothly transitioned after S-shaped acceleration and deceleration interpolation motion.

[0042] According to an embodiment of the present invention, calculating the transition starting point specifically includes: According to Length of segment position track and the actual transition radius Find the The parameter value corresponding to the transition starting point of the segment position trajectory transition segment ; According to The parameter expression of the segment position trajectory is obtained The transition starting point of the segment position trajectory transition segment, which includes calculating the transition starting point straight line trajectory and calculating the transition starting point arc trajectory.

[0043] It should be noted that, in this embodiment, according to Length of segment position track and the actual transition radius Find the The parameter value corresponding to the transition starting point of the segment position trajectory transition segment : , According to the Parameter expressions for segment position trajectories , find the Segment position The transition starting point of the trajectory transition segment, where: Transition start point for straight line trajectory: ; Transition starting point of arc trajectory: .

[0044] According to an embodiment of the present invention, calculating the transition endpoint specifically includes: According to +1 length of position track and the actual transition radius Find the The parameter value corresponding to the transition end point of the segment position trajectory transition segment : According to The parameter expression of the segment position trajectory is obtained The transition end point of the segment position trajectory transition segment, which includes calculating the transition end point straight line trajectory and calculating the transition end point arc trajectory.

[0045] It should be noted that, in this embodiment, according to +1 length of position track and the actual transition radius Find the The parameter value corresponding to the transition starting point of the segment position trajectory transition segment : , According to the Parametric expressions for segment position trajectories , find the Segment position trajectory transition end point of the transition segment, where, Transition end point of a straight line trajectory: ; Arc trajectory transition end point: .

[0046] According to an embodiment of the present invention, calculating the parameter trajectory of the transition section Beerset curve specifically includes: Reparameterization calculation parameters based on Newton's method ; According to the parameters Calculate the control point on the Bezier curve corresponding to the arc length, wherein the control end includes , , , , and ; The transition segment parameter trajectory of the sixth-order Bezier curve is calculated based on the control points.

[0047] It should be noted that in this embodiment, to obtain the parameter position of a certain arc length, the brute force method only requires traversing the integral interval once. , stop when you are close enough to the target arc length value. The brute force method requires a smaller granularity If the arc length of the Bezier curve is very long, many queries are required, which will consume a lot of time. The next section will explain how to use Newton's method to find , we will look for The problem is modeled as: , In order to use Newton's method to obtain the parameters , respectively, The first and second derivatives of : ; ; ; Finally, the parameters The calculation formula is as follows: ; Furthermore, according to the parameters Calculate the control point on the Bezier curve corresponding to the arc length, wherein the control end includes , , , , and ,in, The total number of control points of the Bezier curve is , the parameter expression is as follows: ; ; For the six control points, , , its first-order derivative and second-order derivative are: , ; , , the remaining four control points can be obtained by its derivative: ; ; ; ; But the parameters cannot be analyzed directly and It is difficult to summarize useful rules to simplify parameters to see how different values ​​will affect the transition effect of the position trajectory transition segment. and Therefore, the parameter is introduced Replacement parameters and ,parameter With parameters and The calculation is shown in the formula: .

[0048] According to an embodiment of the present invention, calculating the arc length of a Beerset curve specifically includes: Calculate the arc length of the Bezier curve, set , use the sum of the distances between discrete points in the interval to approximate the length and get the approximate length : ; in, It is the unit of counting for cumulative calculation, and the approximate length is approximated according to the mean value theorem. Get the middle value : ; Among them, when When , the length of the Bezier curve is obtained: ; in, is the parameter trajectory of the transition section Belset curve, The derivative of .

[0049] It should be noted that, in this embodiment, in order to calculate the point on the Bezier curve corresponding to the specified arc length, the arc length of the Bezier curve is first obtained, and the setting , use the sum of the distances between discrete points in the interval to approximate the length and get the approximate length : .

[0050] The approximate length is approximated by the mean value theorem Get the middle value : ; Among them, when When , the length of the Bezier curve is obtained: ; therefore, Bezier curve of The calculation formula of the derivative is as follows: ; .

[0051] According to an embodiment of the present invention, calculating the transition speed according to the constraint condition and completing the transition of adjacent trajectories based on the transition speed specifically includes: Extract length value As the constraint condition, the minimum transition speed of adjacent line segments is obtained as ; Obtaining a Bezier curve transition segment based on the six control points, and calculating a transition speed of each segment based on endpoints on both sides of the transition segment of each segment; The transition between adjacent trajectories is completed based on the corresponding transition speed of each segment.

[0052] It should be noted that, in this embodiment, the line segments in adjacent trajectory segments are connected by the asymmetric S-shaped acceleration and deceleration control method. and Acceleration and deceleration planning is performed, and the quintic Bezier curve of the connecting section is processed at a uniform speed. In order to make the end effector run efficiently, the speed of the transition section is planned to be the minimum speed that can be achieved by the adjacent line segments. The details are as follows: End from point Movement to point When the system uses acceleration and deceleration control to make the terminal speed change from the initial speed to Accelerate and decelerate to the transition point , is the maximum acceleration allowed by the system, then the length of the line segment is The transition speed under the constraint of for: , Similarly, the end point Movement to point When the length of the line segment is The transition speed under the constraint of for: ,

[0053] In addition, the velocity of the end under the constraints of the arc length and interpolation period of the Bezier curve is: , Finally, the transition speed of the transition point at the end is obtained: .

[0054] The third aspect of the present invention provides a computer-readable storage medium, which includes a robot arm trajectory smooth transition method program. When the robot arm trajectory smooth transition method program is executed by a processor, the steps of a robot arm trajectory smooth transition method as described in any one of the above items are implemented.

[0055] The present invention discloses a method, system and readable storage medium for smooth transition of a robot arm trajectory, which adopts a quintic Bezier curve to smoothly transition the connecting corners between adjacent trajectory segments and achieve the optimal speed at the connecting circle, so as to achieve a smooth transition at the connection of multiple trajectory segments, ensure the smoothness and continuity of the movement speed, and effectively improve the operating efficiency of the end effector.

[0056] In the several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as: multiple units or components can be combined, or can be integrated into another system, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the components shown or discussed can be through some interfaces, and the indirect coupling or communication connection of the devices or units can be electrical, mechanical or other forms.

[0057] The units described above as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units; they may be located in one place or distributed on multiple network units; some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0058] In addition, all functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may be separately used as a unit, or two or more units may be integrated into one unit; the above-mentioned integrated units may be implemented in the form of hardware or in the form of hardware plus software functional units.

[0059] A person of ordinary skill in the art can understand that: all or part of the steps of implementing the above method embodiment can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps of the above method embodiment; and the aforementioned storage medium includes: a mobile storage device, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and other media that can store program codes.

[0060] Alternatively, if the above-mentioned integrated unit of the present invention is implemented in the form of a software function module and sold or used as an independent product, it can also be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the embodiment of the present invention can be essentially or partly reflected in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the methods described in each embodiment of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as mobile storage devices, ROM, RAM, magnetic disks or optical disks.

Claims

1. A method for smooth transition of robot arm trajectory, characterized in that: The following steps are involved: Calculate the transition start point and transition end point; Calculate the parameter trajectory of the transition section Belset curve and the arc length of the Belset curve; Calculate the transition speed according to the constraint conditions, and complete the transition of adjacent trajectories based on the transition speed; If the current trajectory is the last transition segment, an S-shaped acceleration and deceleration interpolation motion is performed to complete the smooth transition of all trajectory segments.

2. A robot arm trajectory smooth transition method according to claim 1, characterized in that: Calculate the transition start point, including: According to Length of segment position track and the actual transition radius Find the The parameter value corresponding to the transition starting point of the segment position trajectory transition segment ; According to The parameter expression of the segment position trajectory is obtained The transition starting point of the segment position trajectory transition segment, including the transition starting point of the calculated straight line trajectory and the transition starting point of the calculated arc trajectory.

3. A robot arm trajectory smooth transition method according to claim 2, characterized in that: Calculate the transition endpoint, including: According to +1 length of position track and the actual transition radius Find the The parameter value corresponding to the transition end point of the segment position trajectory transition segment : According to The parameter expression of the segment position trajectory is obtained The transition end point of the segment position trajectory transition segment, including the transition end point of the calculated straight line trajectory and the transition end point of the calculated arc trajectory.

4. A robot arm trajectory smooth transition method according to claim 3, characterized in that: Calculate the parameter trajectory of the transition section Belset curve, including: Reparameterization calculation parameters based on Newton's method ; According to the parameters Calculate the control points on the Bezier curve corresponding to the arc length, where the control points include , , , , and ; The transition segment parameter trajectory of the quintic Bezier curve is calculated based on the control points.

5. A robot arm trajectory smooth transition method according to claim 4, characterized in that: Calculate the arc length of the Belset curve, including: Calculate the arc length of the Bezier curve, set ,in Represents the number of subintervals into which the interval [0,1] is divided. The length is approximated by the sum of the distances between discrete points in the interval. : ； in, It is the unit of counting for cumulative calculation, and the approximate length is approximated according to the mean value theorem. Get the middle value : ； Among them, when When , the length of the Bezier curve is obtained: ； in, is the parameter trajectory of the transition section Belset curve, The derivative of .

6. A robot arm trajectory smooth transition method according to claim 5, characterized in that: The calculating of the transition speed according to the constraint conditions and completing the transition of adjacent tracks based on the transition speed specifically includes: Extract length value As the constraint condition, the minimum transition speed of adjacent line segments is obtained as , where the length value For the The length of the segment position trajectory; Obtaining a Bezier curve transition segment based on the control point, and calculating a transition speed of each segment based on endpoints on both sides of the transition segment of each segment; The transition between adjacent trajectories is completed based on the corresponding transition speed of each segment.

7. A robot arm trajectory smooth transition system, characterized in that: The invention comprises a memory and a processor, wherein the memory comprises a robot arm trajectory smooth transition method program, and the robot arm trajectory smooth transition method program is executed by the processor to implement the following steps: Calculate the transition start point and transition end point; Calculate the parameter trajectory of the transition section Belset curve and the arc length of the Belset curve; Calculate the transition speed according to the constraint conditions, and complete the transition of adjacent trajectories based on the transition speed; If the current trajectory is the last segment, S-shaped acceleration and deceleration interpolation is performed to interpolate each segment of the trajectory and complete the smooth transition of the trajectory.

8. A robot arm trajectory smooth transition system according to claim 7, characterized in that: Calculate the transition start point, including: According to Length of segment position track and the actual transition radius Find the The parameter value corresponding to the transition starting point of the segment position trajectory transition segment ; According to The parameter expression of the segment position trajectory is obtained The transition starting point of the segment position trajectory transition segment, including the transition starting point of the calculated straight line trajectory and the transition starting point of the calculated arc trajectory.

9. A robot arm trajectory smooth transition system according to claim 8, characterized in that: Calculate the transition endpoint, including: According to +1 length of position track and the actual transition radius Find the The parameter value corresponding to the transition end point of the segment position trajectory transition segment : According to The parameter expression of the segment position trajectory is obtained The transition end point of the segment position trajectory transition segment, including the transition end point of the calculated straight line trajectory and the transition end point of the calculated arc trajectory.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium includes a robot arm trajectory smooth transition method program. When the robot arm trajectory smooth transition method program is executed by a processor, the steps of a robot arm trajectory smooth transition method as described in any one of claims 1 to 6 are implemented.

Images