Command Shaping Under Nonsymmetrical Acceleration and Braking Dynamics

Abstract

The conventional unity magnitude zero vibration (UM-ZV) command shaping technique is an effective means for eliminating vibration in linear mechanical systems with on-off actuators. This paper discusses how the UM-ZV command shaping technique is affected by a common nonlinearity: nonsymmetrical accelerating and braking dynamics. Two approaches for creating new types of UM-ZV shaped commands are presented: a closed-form analytic solution and a numerical optimization approach. Both methods reduce residual vibration of the nonlinear system more effectively than the conventional UM-ZV shaped commands. Simulations and experiments on a bridge crane confirm the effectiveness of the new commands.