ON ROBUST IMPEDANCE-FORCE-CONTROL TO A 6-LINK ELECTRO-HYDRAULIC MANIPULATOR WITH DYNAMIC ENVIRONMENT

摘要

An electro-hydraulic manipulator using hydraulic actuators is superior to electrically driven manipulators by power to mass density and insulation. Meanwhile it has many nonlinear elements, and its parameter fluctuations are greater than those ofan electrically driven manipulator. So it is relatively difficult to realize not only stable contact work but also accurate force control for the autonomous assembly tasks using hydraulic manipulators.In this report, compliance control based on the position control by a disturbance observer is applied for 6-link electro-hydraulic manipulator system. And in order to achieve accurate force control even though the contact position of environment isunknown, a reference trajectory modification method is also proposed. Experimental results show that highly robust force tracking by a 6-link electro-hydraulic manipulator can be achieved under various environmental conditions.