Trajectory Planning

Trajectory planning consists in finding a time series of successive joint angles that allows moving a robot from a starting configuration towards a goal configuration, in order to achieve a task, such as grabbing an object from a conveyor belt and placing it on a shelf. This trajectory must respect given constraints: for instance, the robot should not collide with the environment; the joint angles, velocities, accelerations, or torques should be within specified limits, etc. Next, if several trajectories are possible, one should choose the one that optimizes a certain objective, such as the trajectory execution time or energy consumption. This chapter reviews methods to plan trajectories with constraints and optimization objectives relevant to industrial robot manipulators.