Piezoelectric friction-inertia actuator-a critical review and future perspective

This paper provides a comprehensive review of the literature regarding actuator systems which are based on the principle that combines the friction and inertia effect, named friction-inertia principle in this paper; such actuators is called friction-inertial actuator (FIA). The contribution of this paper lies in the generalization of various published (including patented) FIAs into a general principle with three specific principles. They are further taken as a framework upon which various published FIAs are classified and compared in terms of their principle, structure, and performance. In addition, this paper shows how this framework would allow for further innovation on FIAs. In the process of this generalization and classification, some confusion presented in the literature is also clarified. This paper also discusses further effort that may be taken to advance the friction-inertia actuation technology.