Automatic generation of trajectory planners for industrial robots

Abstract

The control of industrial robots is usually divided into several sequential stages. Trajectory planning is an important off-line stage which is concerned with the generation of a time history of a robot's joint position, velocity, acceleration, and input torques. A number of trajectory planning methods have been developed [1], [4]-[6], [10], [11], [13], which usually entail complex computations and algebraic manipulations. Programming this sort of trajectory planners is very complex and error-prone, thereby limiting their applicability. To remove this limitation, we have begun the development of software for automating the trajectory planning, called the Automatic Trajectory Planner Generator (ATPG). This paper describes important components of the ATPG: three trajectory planners, data structures for describing geometric paths, generation of the robot's dynamic equations and constraint functions, and ancillary software. A large portion of the ATPG has been completed, and the remaining portion is currently under development.