Sensorless Torque/Force Control

Motion control systems represent a main subsystem for majority of processing systems that can be found in the industrial sector. These systems are concerned with the actuation of all devices in the manufacturing process such as machines, robots, conveyor systems and pick and place mechanisms such that they satisfy certain motion requirements, e.g., the pre specified reference trajectories are followed along with delivering the proper force or torque to the point of interest at which the process occurs. In general, the aim of force/torque control is to impose the desired force on the environment even if the environment has dynamical motion. The previous motion requirements can be achieved when torque and position/velocity sensors are utilized. However, it is commonly agreed that force/torque sensors have many drawbacks such as (Iida & Ohnishi, 2003; Katsura et al., 2007):