Minimum time-jerk trajectory generation for a mobile articulated manipulator

In this study, we propose a mobile articulated manipulator (MAM) that consists of a suspended three-wheeled platform and a three-link manipulator. Considering the interaction between a suspended platform and a modular manipulator, the system is modeled by a method based on the concept of the direct path method. The Lagrange equation is applied to formulate the dynamic model of the system. To reduce the vibrations of the platform and satisfy motion constraints, the jerk of each joint, which is expressed by the third derivation of the position of the desired joint trajectory with respect to time, is minimized. A new approach based on chaotic particle swarm optimization (CPSO) is developed to find the time-jerk synthetic optimal trajectory of the manipulator using cubic splines. Finally, various simulations for different types of weighting ratios of a cost function are tested using the proposed model. The results reveal the feasibility of the dynamic model and the effectiveness of the presented CPSO method to solve the contradictory problem between high operating efficiency and low mechanical vibrations using limited control energy. © 2014, Chinese Mechanical Engineering Society. All right reserved.