• Kalman Filter based Two-port Body Force Observer
    • Description
      • A flexible joint robot has been researched thoroughly for a variety of purposes 
        • High performance motion control, stable contract response, safety, etc
      • One of the main reasons for using a joint torque sensor in a robot is to measure body forces acting on the system.
      • Especially, the motor actuating torque and the external link torque are important for a flexible joint control. 
      • However, it is difficult to measure or estimate those two torques simultaneously with a single joint torque sensor only due to the lack of information. 
      • Kalman Filter based two-port Body Force OBserver(KF 2-port BFOB) was proposed to estimate two output torques from the motor-side port and the linksideport simultaneously using the two-port system dynamics



    • Experiment
      • The experiment was executed in the vertical situation
      • Simulation scenario
        • constant torque is applied
        • Link is moved by hand
        • In ideal case, link-side port torque will estimate the gravitational torque applied to the link correctly
      • From result,  link-side port torque is almost same as the external torque