Development of Composite State Convergence Schemes for Teleoperation Systems

Abstract

State convergence belongs to a family of model-based control architectures for establishing bilateral communication between the master and slave robots in a teleoperation system. The method provides a systematic procedure to determine the control gains in an elegant way. Originally developed for linear teleoperation systems with small time delays, the method has been extended to nonlinear systems with time-varying delays. However, reliance on the model parameters and a higher number of communication channels remain a limiting factor for the wide adoption of this bilateral control architecture. This thesis addresses these limitations and proposes enhancements in the existing state convergence control architectures to deal with parameter uncertainties and reduce the number of communication channels. The former task is achieved using extended state and nonlinear disturbance observers while the latter objective is accomplished by introducing composite variables. The extension of the proposed bilateral control architectures to the case of multilateral teleoperation systems is also covered. Resultantly, families of robust state convergence control architectures and composite state convergence control architectures are obtained. While constructing the improved control architectures, the elegancy of the state convergence design procedure is retained.