Industrial robot Cartesian space trajectory geometric smoothing method

Abstract

The invention provides an industrial robot Cartesian space trajectory geometric smoothing method. The method comprises the following steps: carrying out parameterization on geometrical curves corresponding to front and back two trajectories in a turning area; calculating parameter values of the geometrical curves of the front and back two trajectories in a turning area connecting point; judging whether the geometrical curves surpass preset limit conditions according to the parameter values of the geometrical curves of the front and back two trajectories in the turning area connecting point and turning radius, and if so, cutting off the geometrical curves; generating a turning area space curve by utilizing the Bezier curve generation principle; calculating terminal velocity and acceleration velocity of the geometrical curves; and generating a turning area trajectory by utilizing a one-dimensional velocity planning algorithm and velocity planning boundary conditions. The method enables the front and back two trajectories of an industrial robot in the turning area to realize geometric superposition smoothing to ensure curvature continuity of the geometrical curves corresponding to the trajectories; and velocity planning is carried out on the smoothed geometrical curves to achieve the purpose of speed control of the turning area.

Description

technical field [0001] The invention relates to the technical field of industrial robots, in particular to a geometric smoothing method for Cartesian space trajectories of industrial robots. Background technique [0002] The motion of an industrial robot in its workspace is composed of trajectories generated by multiple motion commands input by the user. The trajectory (such as straight line and circular arc) generated by each motion command is smooth, and the speed at the endpoint of the trajectory is zero, which is equivalent to the robot needing to stop when moving from one trajectory to the next trajectory, that is, turning, otherwise it will cause violent shaking. If the user does not require the position of the turning point of the two trajectories, the user can smoothly transition from one trajectory to the other without passing through the turning point. [0003] The existing Cartesian space trajectory smoothing methods mainly fall into the following two categories...

AI Technical Summary

Problems solved by technology

However, the special curve often has a sudden change in curvature at the junction with the front and rear trajectories, which in turn causes a sudden change in acceleration.

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