Movement control method of six-degree-of-freedom wrist offset type serial mechanical arm

Abstract

The invention provides a movement control method of a six-degree-of-freedom wrist offset type serial mechanical arm, and relates to the technical field of robot kinematics control methods. The methodcomprises the steps of building a connecting rod coordinate system of the mechanical arm; building a kinematical equation of the mechanical arm; obtaining the angle initial value of a joint 1; calculating the angle values of inverse kinematics solutions of joints 2-6; calculating the error of a pose and a given pose of an end effector; judging whether the error is within the error threshold valuerange; screening out the angle value of one set of inverse kinematics solution meeting the condition; and inputting the angle values of the joints of the mechanical arm into a control module of a known robot to finish movement control over the six-degree-of-freedom wrist offset type serial mechanical arm. The movement control method of the six-degree-of-freedom wrist offset type serial mechanicalarm does not need to consider the singular solution problem based on a Jacobian matrix, simplifies the control process, effectively reduces the calculation amount, improves the convergence rate and calculation precision and improves the control precision of the mechanical arm at the same time.

Description

technical field [0001] The invention relates to the technical field of robot kinematics control methods, in particular to a motion control method of a six-degree-of-freedom wrist offset series mechanical arm. Background technique [0002] Solving robot inverse kinematics is the premise and foundation of robot control. Robots whose three joints at the end do not intersect at one point or whose three axes are not parallel are usually called wrist-biased manipulators. This type of manipulator has the characteristics of high structural strength and flexible movement, but it is difficult to calculate the The inverse kinematics solutions of type manipulators, thus numerical methods are widely used to solve the above problems. The numerical method itself has many limitations, such as slow convergence speed or sometimes no convergence for high-dimensional nonlinear problems, improper selection of initial values ​​will seriously reduce the convergence speed and calculation accuracy,...

AI Technical Summary

Problems solved by technology

The numerical method itself has many limitations, such as slow convergence speed or sometimes no convergence for high-dimensional nonlinear problems, improper selection of initial values ​​will seriously reduce the convergence speed and calculation accuracy, and it is impossible to obtain multiple solutions at the same time, so that some constraints in trajectory planning are difficult. Add, you must avoid singular poses or you will not be able to converge, etc.

These limitations directly lead to problems such as cumbersome control process of this type of robot, large amount of calculation, low control accuracy, and difficulty in realizing online real-time control.

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