Robot Force Control, 1999 The Springer International Series in Engineering and Computer Science Series, Vol. 540

One of the fundamental requirements for the success of a robot task is the capability to handle interaction between manipulator and environment. The quantity that describes the state of interaction more effectively is the contact force at the manipulator's end effector. High values of contact force are generally undesirable since they may stress both the manipulator and the manipulated object; hence the need to seek for effective force control strategies. The book provides a theoretical and experimental treatment of robot interaction control. In the framework of model-based operational space control, stiffness control and impedance control are presented as the basic strategies for indirect force control; a key feature is the coverage of six-degree-of-freedom interaction tasks and manipulator kinematic redundancy. Then, direct force control strategies are presented which are obtained from motion control schemes suitably modified by the closure of an outer force regulation feedback loop. Finally, advanced force and position control strategies are presented which include passivity-based, adaptive and output feedback control schemes. Remarkably, all control schemes are experimentally tested on a setup consisting of a seven-joint industrial robot with open control architecture and force/torque sensor.
The topic of robot force control is not treated in depth in robotics textbooks, in spite of its crucial importance for practical manipulation tasks. In the few books addressing this topic, the material is often limited to single-degree-of-freedom tasks. On the other hand, several results are available in the robotics literature but no dedicated monograph exists. The book is thus aimed at filling this gap by providing a theoretical and experimental treatment of robot force control.

1. Introduction.- 1. Motion control vs. interaction control.- 2. Indirect vs. direct force control.- 3. Experimental apparatus.- 2. Motion Control.- 1. Modeling.- 2. Tracking control.- 3. Regulation.- 4. Further reading.- 3. Indirect Force Control.- 1. Compliance control.- 2. Impedance control.- 3. Six-DOF impedance control.- 4. Further reading.- 4. Direct Force Control.- 1. Force regulation.- 2. Force and motion control.- 3. Force tracking.- 4. Further reading.- 5. Advanced Force and Position Control.- 1. Task space dynamics.- 2. Adaptive control.- 3. Output feedback control.- 4. Further reading.- Appendices.- A — Rigid Body Orientation.- 1. Rotation matrix.- 2. Euler angles.- 3. Angle/axis.- 4. Quaternion.- B — Models of Robot Manipulators.- 1. Kinematic models.- 1.1 Six-joint manipulator.- 1.2 Seven-joint manipulator.- 2. Dynamic models.- 2.1 Six-joint manipulator.- 2.2 Seven-joint manipulator.- References.