Dual notch-type high-order frinction-free force observers for force sensorless fine force control

Abstract

In order to realize a fine force sensorless force control, this paper proposes a new notch-type friction-free disturbance observer(DOB) and a new notch-type friction-free reaction force observer(FFRFO). Generally, a force sensorless force control system always has influence on static friction phenomenon. To overcome this problem, this paper proposes a new force sensorless control system using the notch-type friction free reaction force observer, whose inner system is the proposed acceleration control based on the notch-type friction free disturbance observer. The effectiveness of the proposed system is confirmed by experiments using an actual industrial robot.