Parallel Pre-stressed Actuators (PPA)
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 prestressing frame applies an optimal preloading force to the MLA which ensures a longer lifetime and better performance with dynamic applications than traditional preloaded actuators.
Designed by CEDRAT TECHNOLOGIES, this new direct piezo Actuator results from contracts carried out for CNES, the French Space Agency. The PPA model is lighter than the compacting Direct Piezo Actuator, with the same electromechanical properties. Its compact size also makes integration easier in mechanical assembly.