A bilateral control scheme is introduced to ensure stable teleoperation under
a wide variety of environments and operating speeds. System stability is analyzed in terms
of the time domain definition of passivity. A previously proposed energy-based method
is extended to a 2-port network, and the issues in implementing the “Passivity Observer”
and “Passivity Controller” to teleoperation systems are studied. The method is tested with
our two-DOF master/slave teleoperation system. Stable teleoperation is achieved under
conditions such as hard wall contact (stiffness > 150 kN/m) and hard surface following.
