Path Planning of Manipulator Robots using Mixed Integer Nonlinear Programming

In this paper a new method is proposed for path planning of planar manipulators amid obstacles through mathematical programming in a way that the robot’s links avoid collision with obstacles throughout their motion from an initial to a goal configuration. After inputting the workspace geometry، the shortest feasible path for the robot’s end-effector is planned toward its goal position using Generalized Visibility Graph، which is then interpolated into subgoal points that should be sequentially reached by the end-effector. Next، a Mixed Integer Nonlinear Programming (MINLP) model with the objective of minimizing the distance between the end-effector and the subgoals is successively solved and the angle of each link is determined such that it does not intersect obstacles. In order to enhance the safety of clearance from obstacles، they are enlarged by an offset. Also، the proposed method has been modified and tuned aiming to reduce the number of constraints and 0-1 variables، which led to reduced runtimes.