Minimum time path planning of robotic manipulator in drilling/spot welding tasks

• In this paper, an optimization strategy is proposed for solving minimum time manufacturing path planning in multi points manufacturing tasks.
• According to the start-stop movement in drilling/spot welding task, the path planning problem is converted into a traveling salesman problem (TSP) and a series of point to point minimum time transfer path planning problems.
• Cubic Hermite interpolation polynomial is used to parameterize the transfer path and then the path parameters are optimized to obtain minimum point to point transfer time.
• A new TSP with minimum time index is constructed and then solved by using a classical genetic algorithm (GA).
• Numerical test is executed to demonstrate the effectiveness of the proposed approach.

In this paper, a minimum time path planning strategy is proposed for multi points manufacturing problems in drilling/spot welding tasks. By optimizing the travelling schedule of the set points and the detailed transfer path between points, the minimum time manufacturing task is realized under fully utilizing the dynamic performance of robotic manipulator. According to the start-stop movement in drilling/spot welding task, the path planning problem can be converted into a traveling salesman problem (TSP) and a series of point to point minimum time transfer path planning problems. Cubic Hermite interpolation polynomial is used to parameterize the transfer path and then the path parameters are optimized to obtain minimum point to point transfer time. A new TSP with minimum time index is constructed by using point-point transfer time as the TSP parameter. The classical genetic algorithm (GA) is applied to obtain the optimal travelling schedule. Several minimum time drilling tasks of a 3-DOF robotic manipulator are used as examples to demonstrate the effectiveness of the proposed approach.