Inverse kinematics solution method and system for scara type robot

Abstract

The invention discloses an inverse kinematics solution method and system for a scara robot. The method comprises the following steps that S1, the motion range of each joint of the scara robot is configured; s2, according to the current tail end pose, a kinematics top view of each joint is constructed; s3, according to the current tail end pose, configuration variables of a second joint and a fourth joint are determined; and S4, solving the position or attitude of each joint according to the current position and attitude angle of the tail end and the configuration variables of the second joint and the fourth joint. The invention provides an inverse kinematics solution method and system for a scara type robot, so that inverse kinematics solution can be carried out on the scara robot of which a third joint and a fourth joint generate coupling motion due to a lead screw spline shaft, condition division in the inverse kinematics solution process of the scara robot is reduced, the number of inverse solutions is reduced, and the solution efficiency is improved. Therefore, the calculation efficiency of inverse kinematics is improved.

Description

Technical Field

[0001] The present invention relates to the field of robot control technology, and in particular to a scara-type robot kinematics inverse solution method and system. Background Art

[0002] Inverse kinematics is the process of solving the joint variables required to achieve the position and posture of the robot in space by giving it the position and posture. It enables the robot to accurately calculate the position and angle of each joint of the robot according to the task requirements, thereby achieving the expected motion trajectory and posture.

[0003] The scara robot is an industrial robot designed for assembly operations. It generally has three rotating joints and one moving joint, and is suitable for fast and precise operations on a two-dimensional plane, such as the assembly and placement of electronic components. Calculating the inverse kinematic solution of the scara robot is a necessary condition for the scara robot to walk Cartesian space paths such as straight lines and arcs. However, for a general scara robot, there are multiple inverse solutions for its kinematics. If you want to calculate all the inverse solutions, you need to consider all the solutions of the other joints of the scara robot in this terminal posture, so the calculation process is relatively cumbersome. At the same time, for the scara robot whose third and fourth joints are coupled due to the screw spline shaft, the dynamic effect caused by the joint coupling will make it difficult to solve the inverse kinematic solution of the scara robot. Summary of the invention

[0004] In view of the deficiencies of the above-mentioned prior art, the technical problem to be solved by the present invention is: to provide a method and system for inverse solution of the kinematics of a scara-type robot, so that the kinematics inverse solution of the scara robot in which the third joint and the fourth joint undergo coupled motion due to the screw spline shaft can be solved, and the situation division in the process of solving the inverse solution of the kinematics of the scara robot can be reduced, and the number of inverse solutions can be reduced, thereby improving the computational efficiency of the inverse solution of the kinematics of the scara robot.

[0005] A technical solution adopted by the present invention is to provide a scara-type robot kinematic inverse solution method, comprising the following steps:

[0006] S1: Configure the motion range of each joint of the scara robot;

[0007] S2: Construct a kinematic top view of each joint based on the current end position;

[0008] S3: Determine the configuration variables of the second joint and the fourth joint according to the current end pose;

[0009] S4: Based on the current position and attitude angle of the end, as well as the configuration variables of the second joint and the fourth joint, solve the position or attitude of each joint.

[0010] Furthermore, the step S1 includes the following sub-steps:

[0011] S11: Configure the rotation range of the first joint and the second joint to be (-180, 180) degrees;

[0012] S12: configure the movement range of the third joint to be (-D, D), where D is a positive number in millimeters;

[0013] S13: Configure the rotation range of the fourth joint to be (-180×N, 180×N) degrees, where N is a positive integer.

[0014] Furthermore, step S2 includes the following sub-steps:

[0015] S21: In the kinematic top view, the first arm connecting the first joint and the second joint is denoted as OE, and the length of the first arm is denoted as A1;

[0016] S22: In the kinematic top view, the second arm connecting the second joint and the fourth joint is denoted as ET, and the length of the second arm is denoted as L2;

[0017] S23: In the kinematic top view, the line between the first joint and the fourth joint is denoted as OT, and the length is denoted as L.

[0018] Furthermore, in step S3, the following sub-steps are included:

[0019] S31: record the configuration variable of the second joint as ConfigA2, where A2 represents the rotation angle of the second joint. If A2>0, ConfigA2 takes a value of +1, and if A2<0, ConfigA2 takes a value of -1;

[0020] S32: The configuration variable of the fourth joint is recorded as ConfigA4, where A4 represents the rotation angle of the fourth joint, ConfigA4 is an integer, and the rotation angle interval of A4 is recorded as (-180+ConfigA4×360, 180+ConfigA4×360) degrees.

[0021] Furthermore, in the step S4, the following sub-steps are also included:

[0022] S41: Input the end position and attitude angle, and record the end position as T = [T x ,T y ,T z ], and the attitude angle is recorded as T c , where Tx , T y , T z Respectively represent the three-axis coordinates of the Cartesian space of the end position;

[0023] S42: Calculate ∠OET using the cosine theorem, and calculate the rotation angle A2 of the second joint according to ∠OET and ConfigA2;

[0024] S43: Calculation Rotate around the Z axis to The radian ∠rZ is calculated based on ∠rZ according to calculate according to Calculate the rotation angle A1 of the first joint;

[0025] S44: According to the terminal attitude angle T c , the rotation angle A1 of the first joint, the rotation angle A2 of the second joint and the configuration variable ConfigA4 of the fourth joint, calculate the rotation angle A4 of the fourth joint;

[0026] S45: According to the end Z axis coordinate T z , the fourth joint rotation angle A4 and the third joint pitch pitch, calculate the third joint movement distance A3.

[0027] Furthermore, in the step S42, the following sub-steps are included:

[0028] S421: Using the law of cosines to calculate ∠OET, the specific formula can be expressed as:

[0029]

[0030] Wherein, ∠OET represents the angle between the first arm OE and the second arm ET;

[0031] S422: Calculate the rotation angle A2 of the second joint according to ∠OET and ConfigA2. The specific formula can be expressed as:

[0032] A2 = ConfigA2*(π-∠OET);

[0033] Here, π represents π radians, or 180 degrees.

[0034] Furthermore, the step S43 includes the following sub-steps:

[0035] S431: Calculation Rotate around the Z axis to The radian ∠rZ, the specific formula can be expressed as:

[0036]

[0037] ∠rZ=ConfigA2*(∠OTE-π);

[0038] Among them, ∠OTE represents the angle between OT and TE;

[0039] S432: Calculated based on ∠rZ The specific formula can be expressed as:

[0040]

[0041]

[0042] Among them, rotz(θ) represents the transformation matrix of rotation angle θ around the Z axis;

[0043] S433: According to calculate according to Calculate the rotation angle A1 of the first joint. The specific formula can be expressed as:

[0044]

[0045] in, Representation vector The component on the y-axis, Represents the component of the vector on the x-axis.

[0046] Furthermore, the specific formula of the calculation process in step S44 can be expressed as:

[0047] A4=T c -A1-A26ConfigA4*2*π;

[0048] Among them, T c represents the end posture angle, A1 represents the rotation angle of the first joint, A2 represents the rotation angle of the second joint, and ConfigA4 represents the configuration variable of the fourth joint.

[0049] Furthermore, the specific formula of the calculation process in step S45 can be expressed as:

[0050] A3=T z -A4*pitch;

[0051] Among them, pitch represents the pitch of the third joint.

[0052] In order to solve the above technical problems, the second technical solution adopted by the present invention is: to provide a scara-type robot kinematics inverse solution system, comprising:

[0053] Parameter configuration module, used to configure the motion range of each joint of the scara robot;

[0054] The kinematic top view construction module is used to construct the kinematic top view of each joint according to the current end position;

[0055] A joint variable calculation module is used to determine the configuration variables of the second joint and the fourth joint according to the current end posture;

[0056] The joint posture calculation module is used to solve the position or posture of each joint according to the current position and posture angle of the end and the configuration variables of the second joint and the fourth joint.

[0057] A scara-type robot kinematic inverse solution method and system of the present invention have at least the following beneficial effects: the present invention, through a scara-type robot kinematic inverse solution method, can solve the kinematic inverse solution of a scara robot in which the third joint and the fourth joint undergo coupled motion due to a screw spline shaft, and reduce the situation division in the process of solving the scara robot's kinematic inverse solution, reduce the number of inverse solutions, and make the solution process simple to code and easy to implement, thereby improving the computational efficiency of the scara robot's kinematic inverse solution. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0059] Figure 1 The present invention is a flowchart of an implementation method of a scara-type robot kinematic inverse solution method.

[0060] Figure 2 for Figure 1 Sub-flow chart of step S1 in .

[0061] Figure 3 It is a schematic diagram of the structure of the scara robot of the present invention.

[0062] Figure 4 This is a kinematic top view of the scara robot of the present invention.

[0063] Figure 5 for Figure 1 Sub-flow chart of step S2 in .

[0064] Figure 6 for Figure 1 Sub-flow chart of step S3 in .

[0065] Figure 7 for Figure 1Sub-flow chart of step S4 in .

[0066] Figure 8 It is a structural block diagram of an implementation scheme of a kinematic inverse solution system of the present invention.

[0067] Explanation of the reference numerals: base 11; first arm 12; second arm 13; end effector 14; first joint 21; second joint 22; third joint 23; fourth joint 24. DETAILED DESCRIPTION

[0068] The present invention will be further described below in conjunction with the accompanying drawings.

[0069] See also Figure 1 , is a flow chart of an implementation method of a scara-like robot kinematic inverse solution method of the present invention. This implementation method may specifically include the following steps:

[0070] S1: Configure the range of motion of each joint of the scara robot.

[0071] Specifically, the scara robot is an industrial robot designed specifically for assembly operations. It generally has three rotating joints and one mobile joint. By configuring the motion range of each joint, it can perform fast and precise operations on a two-dimensional plane, such as assembling and placing electronic components.

[0072] See also Figure 2 , this step S1 may include the following sub-steps:

[0073] S11: Configure the rotation range of the first joint 21 and the second joint 22 to be (-180, 180) degrees;

[0074] S12: configuring the movement range of the third joint 23 to be (-D, D), where D is a positive number in millimeters;

[0075] S13: Configure the rotation range of the fourth joint 24 to be (-180×N, 180×N) degrees, where N is a positive integer.

[0076] Specifically, in this embodiment, the specific structure of the scara robot can be found in Figure 3, wherein the end effector 14 is rotatably connected with the fourth joint 24 through the screw spline shaft, i.e. the third joint 23. The rotation of the fourth joint 24 can drive the vertical reciprocating motion of the third joint 23. The first joint 21 is a rotation joint of the forearm, i.e. the first arm 12, which is arranged on the scara robot base 11. The rotation range of the first joint 21 can be set to (-180, 180) degrees. The second joint 22 is a rotation joint of the wrist, i.e. the second arm 13. The rotation range of the second joint 22 can also be set to (-180, 180) degrees. The third joint 23 is a movable joint of the end effector 14. The movable range of the third joint 23 can be set to (-D, D), where D is a positive number in millimeters. The fourth joint 24 is a rotation joint of the end effector 14. The rotation range of the fourth joint 24 can be set to (-180×N, 180×N) degrees, where N is a positive integer.

[0077] S2: Construct a kinematic top view of each joint based on the current end position.

[0078] For details, please refer to Figure 4 The kinematic top view of this scheme is the projection of the scara robot from the Z axis to the XY axis plane, which can reflect the position and state of the first arm 12 and the second arm 13 of the scara robot on the XY axis plane, thereby facilitating the calculation of the inverse kinematic solution of the scara robot.

[0079] See also Figure 5 , this step S2 may include the following sub-steps:

[0080] S21: In the kinematic top view, the first arm 12 connecting the first joint 21 and the second joint 22 is denoted as OE, and the length of the first arm 12 is denoted as L1.

[0081] S22: In the kinematic top view, the second arm 13 connecting the second joint 22 and the fourth joint 24 is denoted as ET, and the length of the second arm 13 is denoted as L2.

[0082] S23: In the kinematic top view, the line between the first joint 21 and the fourth joint 24 is denoted as OT, and the length is denoted as L.

[0083] Specifically, in this embodiment, if Figure 4 As shown, in the kinematic top view, the forearm of the scara robot, i.e. the first arm 12, is denoted as OE, and its length is denoted as L1; the wrist of the scara robot, i.e. the second arm 13, is denoted as ET, and its length is denoted as L2. The length of the line between OT can be denoted as L.

[0084] S3: Determine the configuration variables of the second joint 22 and the fourth joint 24 according to the current end posture.

[0085] Specifically, the configuration variables of the second joint 22 and the fourth joint 24 may be determined according to the current posture of the end effector 14 in the kinematic top view.

[0086] In some embodiments, see Figure 4 , this step S3 may include the following steps:

[0087] S31: Record the configuration variable of the second joint 22 as ConfigA2, where A2 represents the rotation angle of the second joint 22. If A2>0, ConfigA2 takes a value of +1; if A2<0, ConfigA2 takes a value of -1.

[0088] Specifically, in this embodiment, the configuration variable ConfigA2 of the second joint 22 is determined by reading the current position of the end effector 14 in the kinematic top view, where A2 represents the rotation angle of the second joint 22. It should be noted that: Figure 4 In the kinematic top view, there are two situations in which the position of the end effector 14 may correspond to the position of the second joint 22, namely, A2>0, ConfigA2 takes the value of +1, and in this case, in the kinematic top view, the position of E is on the right side of the line from O to T; and A2<0, ConfigA2 takes the value of -1, and in this case, in the kinematic top view, the position of E is on the left side of the line from O to T.

[0089] S32: Record the configuration variable of the fourth joint 24 as ConfigA4, where A4 represents the rotation angle of the fourth joint 24, ConfigA4 is an integer, and the rotation angle interval of A4 is recorded as (-180+ConfigA4×360, 180+ConfigA4×360).

[0090] Specifically, in the present embodiment, the configuration variable ConfigA4 of the fourth joint 24 is determined by reading the current rotation angle of the end effector 14 in the kinematic top view, wherein A4 represents the rotation angle of the fourth joint 24, ConfigA4 takes an integer, and the rotation angle interval of A4 is recorded as (-180+ConfigA4×360, 180+ConfigA4×360). For easier understanding, the calculation process of the configuration variable ConfigA4 is illustrated here by way of example. For example, if the current rotation angle of the end effector 14 in the kinematic top view is between -180 degrees and 180 degrees, ConfigA4=0; if the current rotation angle of the end effector 14 in the kinematic top view is between 180 degrees and 540 degrees, then ConfigA4=1; if the current rotation angle of the end effector 14 in the kinematic top view is between -540 degrees and -180 degrees, then ConfigA4=-1.

[0091] S4: According to the current position and posture angle of the end, and the configuration variables of the second joint 22 and the fourth joint 24, the position or posture of each joint is solved.

[0092] Specifically, in view of the problem of multiple solutions of the scara robot inverse solution in the prior art, when moving in Cartesian space, it is necessary to select the set of solutions that are continuous and non-mutated with the current joint values, and the classification of multiple solutions is somewhat redundant, and the calculation process is cumbersome. This solution only uses configuration variables for the second joint 22 and the fourth joint 24, so that the states of all joints of the scara robot can be calculated, which has the advantages of non-redundant problem division, clear and simple steps, and intuitive methods.

[0093] See also Figure 5 , this step S4 may include the following sub-steps:

[0094] S41: Input the end position and attitude angle, and record the end position as T = [T x ,T y ,T z ], and the attitude angle is recorded as T c , where T x , T y , T z Respectively represent the three-axis coordinates of the Cartesian space of the end position.

[0095] S42: Calculate ∠OET using the law of cosines, and calculate the rotation angle A2 of the second joint 22 based on ∠OET and ConfigA2.

[0096] Specifically, in this embodiment, the rotation angle A2 of the second joint 22 is calculated by the end position, that is, the position and posture angle of the end effector 14 . The specific calculation process is shown in steps S421 and S422 .

[0097] In some embodiments, the step S42 may include the following sub-steps:

[0098] S421: Using the law of cosines to calculate ∠OET, the specific formula can be expressed as:

[0099]

[0100] Wherein, ∠OET represents the angle between the first arm 12, i.e., the line OE, and the second arm 13, i.e., the line ET;

[0101] S422: Calculate the rotation angle A2 of the second joint 22 according to ∠OET and ConfigA2. The specific formula can be expressed as:

[0102] A2 = ConfigA2*(π-∠OET);

[0103] Here, π represents π radians, or 180 degrees.

[0104] Specifically, the above-mentioned step S421 is a process of calculating ∠OET, that is, the angle between the lines OE and ET in the kinematic top view. The angle ∠OET can be calculated by the law of cosines and the above-mentioned known length L1 of the first arm 12, the length L2 of the second arm 13 and the length L of the line between OT. Then, in step S422, the rotation angle A2 of the second joint 22 is calculated according to the angle ∠OET and the calculated ConfigA2. At this point, there are three joint variables left to be calculated.

[0105] S43: Calculation Rotate around the Z axis to The radian ∠rZ is calculated based on ∠rZ according to calculate according to The rotation angle A1 of the first joint 21 is calculated.

[0106] Specifically, this step S43 also calculates the rotation angle A1 of the first joint 21 through the geometric relationship in the kinematic top view.

[0107] In some implementations, this step S43 may include the following sub-steps:

[0108] S431: Calculation Rotate around the Z axis to The radian ∠rZ, the specific formula can be expressed as:

[0109]

[0110] ∠rZ=ConfigA2*(∠OTE-π);

[0111] Among them, ∠OTE represents the angle between OT and TE, and π represents π radians, that is, 180 degrees;

[0112] In this step S431, similarly to step S421, firstly, according to the cosine theorem, the angle ∠OTE between OT and TE in the kinematic top view is calculated, and then according to the calculated configuration variable ConfigA2 of the second joint 22 and the angle ∠OTE, the Rotate around the Z axis to The radian angle ∠rZ.

[0113] S432: Calculated based on ∠rZ The specific formula can be expressed as:

[0114]

[0115] Among them, rotz(θ) represents the transformation matrix of rotating around the Z axis by an angle of θ; rotz(∠rZ) represents the transformation matrix of substituting the angle ∠rZ into θ, that is, rotating around the Z axis by an angle ∠rZ.

[0116] In this step S432, since the position of the end effector 14 is determined, is known, so the vector Calculated Rotate around the Z axis to The radian ∠rZ, and the vector and vector The modulus of , calculate the vector

[0117] S433: According to calculate according to The rotation angle A1 of the first joint 21 is calculated. The specific formula can be expressed as:

[0118]

[0119] in, Representation vector The component on the y-axis, Represents the component of the vector on the x-axis.

[0120] In this step S433, the known vector and the calculated vector Superposition is performed to obtain the position vector of the first joint 21, i.e., the vector Furthermore, the rotation angle A1 of the first joint 21 can be obtained according to the inverse tangent function.

[0121] S44: According to the terminal attitude angle T c , the rotation angle A1 of the first joint 21 , the rotation angle A2 of the second joint 22 , and the configuration variable ConfigA4 of the fourth joint 24 , the rotation angle A4 of the fourth joint 24 is calculated.

[0122] In some embodiments, the specific formula of the calculation process in step S44 can be expressed as:

[0123] A4=T c -A1-A2+ConfigA4*2*π;

[0124] Among them, T c represents the terminal posture angle, A1 represents the rotation angle of the first joint 21, A2 represents the rotation angle of the second joint 22, and ConfigA4 is the configuration variable of the fourth joint 24.

[0125] Specifically, in step S44, according to the determined rotation angle of the end effector 14, that is, the end attitude angle T c , as well as the calculated rotation angle A1 of the first joint 21, the rotation angle A2 of the second joint 22, and the configuration variable ConfigA4 of the fourth joint 24, the rotation angle A4 of the fourth joint 24 is calculated.

[0126] S45: According to the end Z axis coordinate T z , the rotation angle A4 of the fourth joint 24 and the pitch pitch of the third joint 23 , and calculate the movement distance A3 of the third joint 23 .

[0127] In some embodiments, the specific formula of the calculation process in step S45 can be expressed as:

[0128] A3=T z -A4*pitch;

[0129] Herein, pitch represents the pitch of the third joint 23, that is, the pitch of the lead screw.

[0130] Specifically, in step S45, since the third joint 23 is a moving joint, and the third joint 23 and the fourth joint 24 are coupled motions connected by a lead screw spline shaft, the moving distance of the third joint 23 is related to the rotation angle A4 of the fourth joint 24 and the pitch pitch of the lead screw. Therefore, when the rotation angle A4 of the fourth joint 24 and the Z-axis coordinate T of the end effector 14 are known, z After that, the moving distance of the last joint, that is, the third joint 23, can be calculated. So far, according to the current position of the end effector 14, the inverse kinematic solution of the scara robot has been completely solved.

[0131] The present invention uses a scara-type robot kinematic inverse solution method to solve the kinematic inverse solution of a scara robot in which the third joint 23 and the fourth joint 24 undergo coupled motion due to a screw spline shaft, and reduce the situation division in the process of solving the scara robot's kinematic inverse solution, reduce the number of inverse solutions, and thus improve the computational efficiency of the scara robot's kinematic inverse solution.

[0132] See also Figure 6 , is a structural block diagram of an embodiment of the scara-like robot kinematic inverse solution system of the present invention. The scara-like robot kinematic inverse solution system of this embodiment is used to implement a scara-like robot kinematic inverse solution method as described in the above embodiment. Specifically, the scara-like robot kinematic inverse solution system of this embodiment includes a parameter configuration module 100, a kinematic top view construction module 200, a joint variable calculation module 300 and a joint posture calculation module 400. Among them:

[0133] The parameter configuration module 100 is used to configure the motion range of each joint of the scara robot;

[0134] A kinematic top view construction module 200 is used to construct a kinematic top view of each joint according to the current end position;

[0135] The joint variable calculation module 300 is used to determine the configuration variables of the second joint 22 and the fourth joint 24 according to the current end posture;

[0136] The joint posture calculation module 400 is used to solve the position or posture of each joint according to the current position and posture angle of the end, and the configuration variables of the second joint 22 and the fourth joint 24.

[0137] The present invention uses a scara-type robot kinematic inverse solution method to solve the kinematic inverse solution of a scara robot in which the third joint 23 and the fourth joint 24 undergo coupled motion due to a screw spline shaft, and reduce the situation division in the process of solving the scara robot's kinematic inverse solution, reduce the number of inverse solutions, and thus improve the computational efficiency of the scara robot's kinematic inverse solution.

[0138] The above content only expresses the preferred embodiments of the present invention, and its description is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be based on the attached claims.

Claims

1. A scara robot kinematic inverse solution method, characterized in that: The following steps are involved: S1: Configure the range of motion of each joint of the scara robot; S2: Construct a kinematic top view of each joint based on the current end position; S3: Determine the configuration variables of the second joint and the fourth joint according to the current end pose; S4: Based on the current position and attitude angle of the end, as well as the configuration variables of the second joint and the fourth joint, solve the position or attitude of each joint.

2. A scara robot kinematic inverse solution method as claimed in claim 1, characterized in that: The S1 step includes the following sub-steps: S11: Configure the rotation range of the first joint and the second joint to be (-180, 180) degrees; S12: configure the movement range of the third joint to be (-D, D), where D is a positive number in millimeters; S13: Configure the rotation range of the fourth joint to be (-180×N, 180×N) degrees, where N is a positive integer.

3. A scara robot kinematic inverse solution method as claimed in claim 1, characterized in that: The S2 step includes the following sub-steps: S21: In the kinematic top view, the first arm connecting the first joint and the second joint is denoted as OE, and the length of the first arm is denoted as L1; S22: In the kinematic top view, the second arm connecting the second joint and the fourth joint is denoted as ET, and the length of the second arm is denoted as L2; S23: In the kinematic top view, the line between the first joint and the fourth joint is denoted as OT, and the length is denoted as L.

4. A scara robot kinematic inverse solution method as claimed in claim 3, characterized in that: The S3 step includes the following sub-steps: S31: record the configuration variable of the second joint as ConfigA2, where A2 represents the rotation angle of the second joint. If A2>0, ConfigA2 takes a value of +1, and if A2<0, ConfigA2 takes a value of -1; S32: The configuration variable of the fourth joint is recorded as ConfigA4, where A4 represents the rotation angle of the fourth joint, ConfigA4 is an integer, and the rotation angle interval of A4 is recorded as (-180+ConfigA4×360, 180+ConfigA4×360) degrees.

5. A scara robot kinematic inverse solution method as claimed in claim 4, characterized in that: In the step S4, the following sub-steps are also included: S41: Input the end position and attitude angle, and record the end position as T = [T x ,T y ,T z ], and the attitude angle is recorded as T c , where T x , T y , T z Respectively represent the three-axis coordinates of the Cartesian space of the end position; S42: Calculate ∠OET using the cosine theorem, and calculate the rotation angle A2 of the second joint according to ∠OET and ConfigA2; S43: Calculation Rotate around the Z axis to The radian ∠rZ is calculated based on ∠rZ according to calculate according to Calculate the rotation angle A1 of the first joint; S44: According to the terminal attitude angle T c , the rotation angle A1 of the first joint, the rotation angle A2 of the second joint and the configuration variable ConfigA4 of the fourth joint, calculate the rotation angle A4 of the fourth joint; S45: According to the end Z axis coordinate T z , the fourth joint rotation angle A4 and the third joint pitch pitch, calculate the third joint movement distance A3.

6. A scara robot kinematic inverse solution method as claimed in claim 5, characterized in that: In the step S42, the following sub-steps are included: S421: Using the law of cosines to calculate ∠OET, the specific formula can be expressed as: Wherein, ∠OET represents the angle between the first arm OE and the second arm ET; S422: Calculate the rotation angle A2 of the second joint according to ∠OET and ConfigA2. The specific formula can be expressed as: A2 = ConfigA2*π-∠OET); Here, π represents π radians, or 180 degrees.

7. A scara robot kinematic inverse solution method as claimed in claim 6, characterized in that: The step S43 includes the following sub-steps: S431: Calculation Rotate around the Z axis to The radian ∠rZ, the specific formula can be expressed as: ∠rZ=ConfigA2*∠OTE-π); Among them, ∠OTE represents the angle between OT and TE; S432: Calculated based on ∠rZ The specific formula can be expressed as: Among them, rotz(θ) represents the transformation matrix of rotation angle θ around the Z axis; S433: According to calculate according to Calculate the rotation angle A1 of the first joint. The specific formula can be expressed as: in, Representation vector The component on the y-axis, Represents the component of the vector on the x-axis.

8. A scara robot kinematic inverse solution method as claimed in claim 7, characterized in that: The specific formula of the calculation process in step S44 can be expressed as: A4=T c -A1-A2+ConfigA4*2*π; Among them, T c represents the end posture angle, A1 represents the rotation angle of the first joint, A2 represents the rotation angle of the second joint, and ConfigA4 represents the configuration variable of the fourth joint.

9. A scara robot kinematic inverse solution method as claimed in claim 8, characterized in that: The specific formula of the calculation process in step S45 can be expressed as: A3=T z -A4*pitch; Among them, pitch represents the pitch of the third joint.

10. A scara-like robot kinematics inverse solution system, characterized in that: include: Parameter configuration module, used to configure the motion range of each joint of the scara robot; The kinematic top view construction module is used to construct the kinematic top view of each joint according to the current end position; A joint variable calculation module is used to determine the configuration variables of the second joint and the fourth joint according to the current end posture; The joint posture calculation module is used to solve the position or posture of each joint according to the current position and posture angle of the end and the configuration variables of the second joint and the fourth joint.

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