Passive Control of Overhead Cranes

Abstract

The focus of this paper is on the design of optimal passive controllers for rest-to-rest maneuvers of flexible structures. The parameters of the passive controller are determined by formulating an optimization problem to minimize the integral of the time absolute error, subject to control constraints. Appropriate outputs are selected, resulting in passive input-output transfer functions for the plant. The design technique is first illustrated on the benchmark floating oscillator problem. This technique is then used to design dissipative controllers for two models of overhead cranes. In the first model, a crane has a cable/mass combination that is assumed to be a rigid link; in the second model, the wave equation is used to represent the dynamics of the cable. Numerical results illustrate the effectiveness of the proposed technique.