ABSTRACT
This chapter covers a different class of sensors, called effort sensors, which include force, torque, tactile, and impedance. A mechanical system responds to an excitation made through an “effort” such as a force or a torque applied to it. In addition to point forces and torques, an effort may be applied as a distributed force or torque of “touch” such as tactile force. The forces and torques that are present in a dynamic system are generally functions of time. Performance monitoring and evaluation, failure detection and diagnosis, testing, experimental modeling, and control of mechanical dynamic systems can depend heavily on the accurate measurement of associated forces and torques. From the point of view of accuracy, the force sensor has to be located exactly at the place where the force information is needed. Sometimes, however, it may be difficult to place the sensor at the required location.
