Parallel Pre-stressed Actuators (PPA)

The parallel pre-stressed actuator is a preloaded stack of low voltage piezoelectric ceramics (MLA). The preload (or pre-stress) is obtained from an external spring frame made of stainless steel which protects the MLA against tensile force and provides mechanical interfaces for the user allowing an easier integration. This pre-stressing frame applies an optimal preloading force to the MLA which ensures a longer lifetime and better performance with dynamic applications than traditional preloaded actuators.