General avoidance method and system for singular point of mechanical arm

Abstract

The invention discloses a general avoidance method and system for a singular point of a mechanical arm, and belongs to the technical field of avoidance of singular points of mechanical arms. The technical problem to be solved is to provide the improvement of the general avoidance method for the singular point of the mechanical arm. According to the technical scheme for solving the technical scheme, the method comprises the following steps that a kinematic model of the mechanical arm is established, a reference joint coordinate system is established, the spinor of each joint is calculated according to the spinor theory, and a Jacobian matrix is solved; a condition number is calculated by using a joint angle value of a tracing point and the Jacobian matrix; the condition number is used for judging whether the mechanical arm is close to the singular point or not, and after it is judged that the mechanical arm is about to approach the singular point, the mechanical arm uses a singularity avoidance algorithm to calculate a singularity avoidance tracing point till the condition number of the Jacobian matrix of the generated tracing point meets the state of being away from the singular point and the tracing point returns to an original Cartesian trajectory again; and after the singularity avoidance trajectory is planned, smoothing processing and trajectory interpolation are conducted on the planned singularity avoidance trajectory, and a final singularity avoidance trajectory is obtained; The invention is applied to the mechanical arm.

Description

technical field [0001] The invention discloses a general avoidance method and system for a singularity point of a manipulator, and belongs to the technical field of a general avoidance method and system for a singularity point of a manipulator. Background technique [0002] The research and use of robotic arms such as industrial robots, collaborative robots, and medical assistance robotic arms are also advancing. Especially in the industrial field, the emergence and application of industrial robots have subverted the traditional industrial model, saved a lot of manpower, material resources and labor production costs, greatly improved production efficiency, replaced personnel in production in dangerous working environments, and avoided a large number of personal accidents. occur. , is of great significance and plays a major role in promoting the automation of industrial production. [0003] At the same time, due to the structural characteristics of the manipulator, it is in...

AI Technical Summary

Problems solved by technology

[0004] The spherical wrist-joint robot is a mechanical arm with three continuous axes intersecting at one point, and the characteristic that the three continuous axes at the end intersect at one point also makes it easier to use the Jacobian matrix for singularity analysis; non-spherical wrist-joint manipulators The three axes at the end do not intersect at one point, and its end position is highly coupled with the attitude. It is difficult to analyze and avoid the singularity using the Jacobian matrix, and the calculation cost is relatively large.

[0005] The application number is 202011439303.5, and the Chinese invention patent named a non-spherical wrist manipulator singular point avoidance method and system discloses that the singularity factor derivation of the non-spherical wrist manipulator is realized by using the Jacobian matrix change method, but for some aspherical wrist manipulators As far as the articulated manipulator is concerned, due to the high coupling of its terminal position and attitude and the particularity of its configuration, its Jacobian matrix is ​​quite complicated. If only the Jacobian matrix is ​​used to solve the numerical solution of its determinant, the computational cost is acceptable. However, it is very difficult to solve a series of transformations such as matrix transformation of the Jacobian matrix to solve the sub-matrix, invert the sub-matrix, and solve the singular factor.

Images