2015 Volume 2 Issue 4 Pages 15-00038
This paper proposes a trajectory planning method for a transfer system on a two-dimensional (2-D) surface. The 2-D transfer system must ensure safe and rapid transfer of an object. Safe transport of objects containing vibrational elements requires vibration suppression and obstacle avoidance. Meanwhile, the transport time should be short and should satisfy the constraints of the transfer system. Our approach adds a reference trajectory to the transfer control system. The reference trajectory is derived by minimizing the integral square errors of the transferred object and the goal positions, and the energy of the frequency bands which include the natural frequencies of the vibrational elements. This optimization problem constrains the acceleration, velocity, and position of the transfer system. Angularly postured obstacles impose additional ellipsoidal constraints on the position of the transferred object. The trajectory planning problem is formulated as a quadratic problem with quadratic constraints. The effectiveness of the proposed trajectory planning is verified in simulations of an omni-directional mobile vehicle carrying the liquid container.