procedure for controlling a industrirobots movement in and in the vicinity of the singulariteter

摘要

The invention relates to a method for controlling an industrial robot such that a tool supported by the robot is able to follow a path which is determined by a number of consecutive points, and wherein the robot while following the path ends up near or at a singularity. The robot has a plurality of movement axes and its configuration is determined by the angles of rotation of the movement axes. The angles of rotation which are to be assumed by the robot in order to obtain the desired position and orientation for the tool at the next point on the path are calculated by an iterative method. The ratio of the angular velocities of the axes to the velocity of the tool is given by a Jacobian matrix. By means of the Jacobian matrix it is determined whether the robot is at or near a singularity. The intention of the invention is to control the iteration such that the position of the tool remains correct through the singularity. A certain error in the orientation of the tool may be accepted. At a singularity the importance of the position errors is increased by weighting these errors during the iteration in relation to the orientation errors while at the same time locking the singular axes. IMAGE