Robotic arm trajectory smooth transition method, system and readable storage medium

Abstract

The present invention discloses a method, system, and readable storage medium for smooth transition of a robot arm trajectory, wherein the method includes: calculating the transition starting point and transition end point; calculating the parameter trajectory of the transition segment's Bezier curve and the arc length of the Bezier curve; calculating the transition speed according to the constraint conditions, and completing the transition of adjacent trajectories based on the transition speed; if the current trajectory is the last transition segment, performing S-shaped acceleration and deceleration interpolation motion to complete the smooth transition of all trajectories. The present invention uses a quintic Bezier curve between adjacent trajectory segments to obtain a smooth transition trajectory at the connecting corner, and by obtaining the optimal speed at the connecting point, it can achieve a smooth transition at the connecting point of multiple trajectory segments, ensuring the smoothness and continuity of the motion speed, and effectively improving the operating efficiency of the end effector.

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 a robot arm trajectory. 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, because the transition corners at the connection of multiple trajectory segments of industrial robots are sharp, the acceleration and deceleration control method with zero initial and final speed is adopted when interpolating discrete small line segments. However, this method will cause continuous sudden changes in the speed direction during the entire interpolation process. In other words, the frequent start and stop of the drive axis will affect the accuracy of motion positioning. Therefore, how to perform high-speed and stable motion control 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 robot arm trajectories, which adopts quintic Bezier curves to smoothly transition at the connecting corners between adjacent trajectory segments and achieve the optimal speed at the connecting circle, so as to achieve smooth transition at the connection of multiple trajectory segments, ensure the smoothness and continuity of the motion 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:

[0006] Calculate the transition start point and transition end point;

[0007] Calculate the parameter trajectory and arc length of the Belset curve in the transition section;

[0008] Calculate the transition speed according to the constraint conditions and complete the transition of adjacent trajectories based on the transition speed;

[0009] 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.

[0010] In this solution, the calculation of the transition starting point includes:

[0011] 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 ;

[0012] 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 solution, the calculation of the transition endpoint includes:

[0014] According to +1 length of the 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 :

[0015] 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.

[0016] In this solution, the parameter trajectory of the transition section Belset curve is calculated, specifically including:

[0017] Reparameterization calculation parameters based on Newton method ;

[0018] 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;

[0019] A transition segment parameter trajectory of the quintic Bezier curve is calculated based on the control points.

[0020] In this solution, the arc length of the Belset curve is calculated, specifically including:

[0021] 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 to get the approximate length :

[0022] ;

[0023] in, It is the unit of cumulative calculation, and the approximate length is obtained based on the mean value theorem. Get the middle value :

[0024] ;

[0025] Among them, when , the length of the Bezier curve is obtained:

[0026] ;

[0027] in, is the parameter trajectory of the transition section Belset curve, The derivative of .

[0028] In this solution, the calculation of the transition speed according to the constraint conditions and the completion of the transition of adjacent trajectories based on the transition speed specifically include:

[0029] Extract length value As the constraint condition, the minimum transition speed of adjacent line segments is obtained as ;

[0030] 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;

[0031] The transition between adjacent trajectories is completed based on the corresponding transition speed of each segment.

[0032] A 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:

[0033] Calculate the transition start point and transition end point;

[0034] Calculate the parameter trajectory and arc length of the Belset curve in the transition section;

[0035] Calculate the transition speed according to the constraint conditions and complete the transition of adjacent trajectories based on the transition speed;

[0036] 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.

[0037] In this solution, the calculation of the transition starting point includes:

[0038] 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 ;

[0039] 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.

[0040] In this solution, the calculation of the transition endpoint includes:

[0041] According to +1 length of the 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 :

[0042] 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.

[0043] In this solution, the parameter trajectory of the transition section Belset curve is calculated, specifically including:

[0044] Reparameterization calculation parameters based on Newton method ;

[0045] According to the parameters Calculate the control point on the Bezier curve corresponding to the arc length, wherein the control end includes 、 、 、 、 and ;

[0046] A transition segment parameter trajectory of the quintic Bezier curve is calculated based on the control points.

[0047] In this solution, the arc length of the Belset curve is calculated, specifically including:

[0048] 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 to get the approximate length :

[0049] ;

[0050] in, It is the unit of cumulative calculation, and the approximate length is obtained based on the mean value theorem. Get the middle value :

[0051] ;

[0052] Among them, when , the length of the Bezier curve is obtained:

[0053] ;

[0054] in, is the parameter trajectory of the transition section Belset curve, The derivative of .

[0055] In this solution, the calculation of the transition speed according to the constraint conditions and the completion of the transition of adjacent trajectories based on the transition speed specifically include:

[0056] Extract length value As the constraint condition, the minimum transition speed of adjacent line segments is obtained as ;

[0057] Obtaining five transition segments based on the six control points, and calculating a transition speed of each segment based on endpoints on both sides of the transition segment;

[0058] The transition between adjacent trajectories is completed based on the corresponding transition speed of each segment.

[0059] 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.

[0060] The present invention discloses a method, system and readable storage medium for smooth transition of a robot arm trajectory, which uses a quintic Bezier curve to smoothly transition at the connecting corners between adjacent trajectory segments and achieve the optimal speed at the connecting circle. This can 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

[0061] 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;

[0062] Figure 2 A flow chart of a method for smooth transition of a robot arm trajectory according to the present invention is shown;

[0063] Figure 3 A block diagram of a robot arm trajectory smooth transition system according to the present invention is shown. DETAILED DESCRIPTION

[0064] In order to more clearly understand the above-mentioned objects, 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, in the absence of conflict, the embodiments of the present application and the features therein can be combined with each other.

[0065] 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 scope of protection of the present invention is not limited to the specific embodiments disclosed below.

[0066] In order to solve the problem of high-speed and smooth motion control, speed control of the end 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 a 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 end 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.

[0067] Specifically, Figure 1 A flow chart of a method for smooth transition of a robot arm trajectory of the present application is shown.

[0068] like Figure 1 As shown, the present application discloses a method for smooth transition of a robot arm trajectory, comprising the following steps:

[0069] S102, calculating the transition starting point and transition end point;

[0070] S104, calculating the parameter trajectory and arc length of the Belset curve of the transition section;

[0071] S106, calculating the transition speed according to the constraint conditions, and completing the transition of adjacent trajectories based on the transition speed;

[0072] S108: If the current trajectory is the last transition segment, an S-shaped acceleration / deceleration interpolation motion is performed to complete the smooth transition of the current trajectory.

[0073] It should be noted that, in this embodiment, Figure 2As shown in the figure, 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 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 smooth transition is completed after performing S-shaped acceleration and deceleration interpolation motion.

[0074] According to an embodiment of the present invention, calculating the transition starting point specifically includes:

[0075] 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 ;

[0076] 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.

[0077] 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 :

[0078] ,

[0079] According to the Parameter expression of segment position trajectory , find the Segment position trajectory transition starting point of the transition segment, where

[0080] Transition starting point of straight line trajectory: ;

[0081] Transition starting point of arc trajectory: .

[0082] 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.

[0083] According to an embodiment of the present invention, calculating the transition endpoint specifically includes:

[0084] According to +1 length of the 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 :

[0085] 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 calculation of the transition end point straight line trajectory and the calculation of the transition end point arc trajectory.

[0086] It should be noted that, in this embodiment, according to +1 length of the 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 :

[0087] According to the Parameter expression of segment position trajectory , find the The transition end point of the segment position trajectory transition segment, where

[0088] Transition end point of a straight line trajectory: ;

[0089] Arc trajectory transition end point: .

[0090] in, For the The radius of the circle on which the segment arc trajectory lies, For the The central angle of the arc segment trajectory, is the transition parameter of the segment trajectory.

[0091] According to an embodiment of the present invention, calculating the parameter trajectory of the transition section Beerset curve specifically includes:

[0092] Reparameterization calculation parameters based on Newton method ;

[0093] According to the parameters Calculate the control point on the Bezier curve corresponding to the arc length, wherein the control end includes 、 、 、 、 and ;

[0094] A transition segment parameter trajectory of the quintic Bezier curve is calculated based on the control points.

[0095] 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 it is 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 following section will explain how to use Newton's method to find , for which we will look for The problem is modeled as:

[0096] ,

[0097] 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, to obtain The first and second derivatives of :

[0098] ;

[0099] ;

[0100] ;

[0101] Finally, the parameters The calculation formula is as follows:

[0102] ;

[0103] 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 order Bezier curve is , the parameter expression is as follows:

[0104] ;

[0105] ;

[0106] 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:

[0107] ;

[0108] ;

[0109] ;

[0110] ;

[0111] But the parameters cannot be analyzed directly and It is difficult to summarize useful rules to simplify parameters based on the effect of different values on the transition effect of the position trajectory transition section. and Therefore, the parameter Replacement parameters and ,parameter With parameters and The calculation is shown in the formula:

[0112] .

[0113] According to an embodiment of the present invention, calculating the arc length of a Beerset curve specifically includes:

[0114] 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 to get the approximate length :

[0115] ;

[0116] in, It is the unit of cumulative calculation, and the approximate length is obtained based on the mean value theorem. Get the middle value :

[0117] ;

[0118] Among them, when , the length of the Bezier curve is obtained:

[0119] ;

[0120] in, is the parameter trajectory of the transition section Belset curve, The derivative of .

[0121] 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 value of , use the sum of the distances between discrete points in the interval to approximate the length to get the approximate length :

[0122]

[0123] The approximate length is obtained by approximating it according to the mean value theorem Get the middle value :

[0124] ;

[0125] Among them, when , the length of the Bezier curve is obtained:

[0126] ;

[0127] therefore, Order Bezier curve The calculation formula of the derivative is as follows:

[0128] ;

[0129] .

[0130] According to an embodiment of the present invention, calculating the transition speed according to the constraint conditions and completing the transition of adjacent trajectories based on the transition speed specifically includes:

[0131] Extract length value As the constraint condition, the minimum transition speed of adjacent line segments is obtained as ;

[0132] 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;

[0133] The transition between adjacent trajectories is completed based on the corresponding transition speed of each segment.

[0134] 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 Perform acceleration and deceleration planning and perform uniform speed processing on the fifth-order Bezier curve of the transition section. 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:

[0135] End from point Movement to point When the system uses acceleration and deceleration control to make the terminal speed from the initial speed 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:

[0136] ,

[0137] Similarly, the end point Movement to point When the length of the line segment is The transition speed under the constraint of for:

[0138] ,

[0139] In addition, the velocity of the end under the constraints of the Bezier curve arc length and interpolation period is:

[0140] ,

[0141] Finally, the transition speed of the transition point at the end is obtained:

[0142] .

[0143] Figure 3 A block diagram of a robot arm trajectory smooth transition system according to the present invention is shown.

[0144] 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:

[0145] Calculate the transition start point and transition end point;

[0146] Calculate the parameter trajectory and arc length of the Belset curve in the transition section;

[0147] Calculate the transition speed according to the constraint conditions and complete the transition of adjacent trajectories based on the transition speed;

[0148] If the current trajectory is the last segment, S-shaped acceleration and deceleration interpolation is performed to complete the smooth transition of the trajectory after interpolation motion of each segment.

[0149] It should be noted that, in this embodiment, Figure 2 As shown in the figure, 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 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 smooth transition is completed after performing S-shaped acceleration and deceleration interpolation motion.

[0150] According to an embodiment of the present invention, calculating the transition starting point specifically includes:

[0151] 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 ;

[0152] 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, which includes the calculation of the transition starting point straight line trajectory and the calculation of the transition starting point arc trajectory.

[0153] 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 :

[0154] ,

[0155] According to the Parameter expression of segment position trajectory , find the Segment position trajectory transition starting point of the transition segment, where

[0156] Transition starting point of straight line trajectory: ;

[0157] Transition starting point of arc trajectory: .

[0158] According to an embodiment of the present invention, calculating the transition endpoint specifically includes:

[0159] According to +1 length of the 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 :

[0160] 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 calculation of the transition end point straight line trajectory and the calculation of the transition end point arc trajectory.

[0161] It should be noted that, in this embodiment, according to +1 length of the 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 :

[0162] ,

[0163] According to the Parameter expression of segment position trajectory , find the The transition end point of the segment position trajectory transition segment, where

[0164] Transition end point of a straight line trajectory: ;

[0165] Arc trajectory transition end point: .

[0166] According to an embodiment of the present invention, calculating the parameter trajectory of the transition section Beerset curve specifically includes:

[0167] Reparameterization calculation parameters based on Newton method ;

[0168] According to the parameters Calculate the control point on the Bezier curve corresponding to the arc length, wherein the control end includes 、 、 、 、 and ;

[0169] A transition segment parameter trajectory of a sixth-order Bezier curve is calculated based on the control points.

[0170] 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 it is 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 following section will explain how to use Newton's method to find , for which we will look for The problem is modeled as:

[0171] ,

[0172] In order to use Newton's method to obtain the parameters , respectively, to obtain The first and second derivatives of :

[0173] ;

[0174] ;

[0175] ;

[0176] Finally, the parameters The calculation formula is as follows:

[0177] ;

[0178] 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 order Bezier curve is , the parameter expression is as follows:

[0179] ;

[0180] ;

[0181] 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:

[0182] ;

[0183] ;

[0184] ;

[0185] ;

[0186] But the parameters cannot be analyzed directly and It is difficult to summarize useful rules to simplify parameters based on the effect of different values on the transition effect of the position trajectory transition section. and Therefore, the parameter Replacement parameters and ,parameter With parameters and The calculation is shown in the formula:

[0187] .

[0188] According to an embodiment of the present invention, calculating the arc length of a Beerset curve specifically includes:

[0189] 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 to get the approximate length :

[0190] ;

[0191] in, It is the unit of cumulative calculation, and the approximate length is obtained based on the mean value theorem. Get the middle value :

[0192] ;

[0193] Among them, when , the length of the Bezier curve is obtained:

[0194] ;

[0195] in, is the parameter trajectory of the transition section Belset curve, The derivative of .

[0196] 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 value of , use the sum of the distances between discrete points in the interval to approximate the length to get the approximate length :

[0197] .

[0198] The approximate length is obtained by approximating it according to the mean value theorem Get the middle value :

[0199] ;

[0200] Among them, when , the length of the Bezier curve is obtained:

[0201] ;

[0202] therefore, Order Bezier curve The calculation formula of the derivative is as follows:

[0203] ;

[0204] .

[0205] According to an embodiment of the present invention, calculating the transition speed according to the constraint conditions and completing the transition of adjacent trajectories based on the transition speed specifically includes:

[0206] Extract length value As the constraint condition, the minimum transition speed of adjacent line segments is obtained as ;

[0207] 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;

[0208] The transition between adjacent trajectories is completed based on the corresponding transition speed of each segment.

[0209] 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 Perform acceleration and deceleration planning and perform uniform speed processing on the fifth-order Bezier curve of the transition section. 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:

[0210] End from point Movement to point When the system uses acceleration and deceleration control to make the terminal speed from the initial speed 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:

[0211] ,

[0212] Similarly, the end point Movement to point When the length of the line segment is The transition speed under the constraint of for:

[0213] ,

[0214] In addition, the velocity of the end under the constraints of the Bezier curve arc length and interpolation period is:

[0215] ,

[0216] Finally, the transition speed of the transition point at the end is obtained:

[0217] .

[0218] 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, it implements the steps of a robot arm trajectory smooth transition method as described in any one of the above items.

[0219] The present invention discloses a method, system and readable storage medium for smooth transition of a robot arm trajectory, which uses a quintic Bezier curve to smoothly transition at the connecting corners between adjacent trajectory segments and achieve the optimal speed at the connecting circle. This can 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.

[0220] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, 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.

[0221] 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 across multiple network units; some or all of the units may be selected according to actual needs to achieve the purpose of the scheme of this embodiment.

[0222] 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.

[0223] Those skilled in the art will appreciate that all or part of the steps of the above-mentioned method embodiments may be implemented by hardware associated with program instructions, and the aforementioned program may be stored in a computer-readable storage medium. When the program is executed, the program executes the steps of the above-mentioned method embodiments. The aforementioned storage medium includes various media that can store program codes, such as mobile storage devices, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical disks.

[0224] Alternatively, if the integrated units described above are implemented as software modules and sold or used as standalone products, they can also be stored on a computer-readable storage medium. Based on this understanding, the technical solutions of the embodiments of the present invention, or the portion that contributes to the prior art, can be embodied in the form of a software product. This computer software product, stored on a storage medium, includes instructions for enabling a computer device (such as a personal computer, server, or network device) to execute all or part of the methods described in various embodiments of the present invention. The aforementioned storage media include various media capable of storing program code, such as removable storage devices, ROM, RAM, magnetic disks, or optical disks.

Claims

1. A method for smooth transition of a robot arm trajectory, characterized in that: The following steps are involved: Calculate the transition start point and transition end point; Calculate the parameter trajectory and arc length of the Bezier curve in the transition section; 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; 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; ; Transition starting point of straight line trajectory: ; Transition starting point of arc trajectory: ; 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 The end point of the segment position trajectory; According to Length of segment 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; ； Transition end point of a straight line trajectory: ; Arc trajectory transition end point: ; in, For the The radius of the circle on which the segment arc trajectory lies, For the The central angle of the arc segment trajectory, is the transition parameter of the segment trajectory.

2. A robot arm trajectory smooth transition method according to claim 1, characterized in that: Calculate the Bezier curve parameter trajectory of the transition section, including: Reparameterization calculation parameters based on Newton method ; According to the parameters Calculate the control points on the Bezier curve corresponding to the arc length, where the control points include 、 、 、 、 and ; A transition segment parameter trajectory of the quintic Bezier curve is calculated based on the control points.

3. A robot arm trajectory smooth transition method according to claim 2, characterized in that: Calculate the arc length of a Bezier curve, including: Calculate the arc length of the Bezier curve, set ,in Indicates the number of subintervals that the interval [0,1] is divided into. The approximate length is obtained by approximating the length by the sum of the distances between discrete points in the interval. : ； in, It is the unit of cumulative calculation, and the approximate length is obtained based on the mean value theorem. Get the middle value : ； Among them, when , the length of the Bezier curve is obtained: ； in, is the parameter trajectory of the Bezier curve in the transition section, for The derivative of .

4. A method for smooth transition of a robot arm trajectory according to claim 3, characterized in that: The calculating of the transition speed according to the constraint conditions 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 , 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.

5. A robot arm trajectory smooth transition system, characterized in that: The system comprises 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 and arc length of the Bezier curve in the transition section; 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; 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; ; Transition starting point of straight line trajectory: ; Transition starting point of arc trajectory: ; 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 The end point of the segment position trajectory; According to +1 length of the 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; ； Transition end point of a straight line trajectory: ; Arc trajectory transition end point: ; in, For the The radius of the circle on which the segment arc trajectory lies, For the The central angle of the arc segment trajectory, is the transition parameter of the segment trajectory.

6. 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 4 are implemented.

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