Dynamics-Based Trajectory Planning for Vibration Suppression of a Flexible Long-Reach Robotic Manipulator System

We address the unique challenge of vibration sup- pression for a flexible long-reach robotic manipulator system, namely, the through-wall deployment (TWD) system that is used in nuclear environments. This paper proposes a novel dynamics- based trajectory optimization approach, which minimizes both the acceleration and the jerk at the manipulator’s joints, as well as the vibrations of the flexible long-reach boom where the manipulator’s base is mounted. Firstly, we create an integrated model for the system dynamics based on the knowledge of the robotic manipulator and the acceleration data from the vibration tests. We then develop an original procedure for generating the high-order polynomial trajectory that guarantees the zero-boundary condition for a flexible number of optimization parameters and waypoints. Following the simulation of a multi-objective optimization scheme, the optimized trajectory is experimentally validated on the practical TWD system with around 28% vibration reduction on average compared to the benchmark. Importantly, this reduction is achieved without compromising on the average speed of motion. The methodology is transferable to a wider range of flexible robotic manipulator systems with similar characteristics.