Passivity-Based Observer Design for State Affine Systems Using Interconnection and Damping Assignment

A passivity-based observer design is presented for state affine systems. The observer convergence is addressed by systematically determining the output injection so that the observer error dynamics takes the form of an autonomous, passive port-Hamiltonian system. In this respect, the design resembles the interconnection and damping assignment passivity-based controller (IDA-PBC) used for the feedback stabilization of port-Hamiltonian systems. The observer performance is analyzed and illustrated in simulation examples.