The development of a polymeric piezoelectric bimorph microactuator-based macroactuator for an artificial hand

There exists an ongoing need in the area of artificial hands for lightweight and compact actuators. The scope of this dissertation is to show that a polymeric piezoelectric bimorph actuator can simultaneously produce both the force and deflection required to actuate an artificial hand and meet the volume and weight constraints.;The research approach chosen had six steps: microactuator and macroactuator design, mathematical models of these actuators, sensitivity analysis, manufacturing, experimental verification, and parameter analysis for design. In the design phase a small polymeric piezoelectric semicircular shaped bimorph actuator, called a microactuator, was designed to be a building block that can be combined to create larger actuators called macroactuators. By combining microactuators in series deflection is increased, and by combining them in parallel the force is increased. By creating a mixed combination, also called a macroactuator, significant force and deflection are obtained.;The steady-state deflection and force for the microactuator and the macroactuator designs were mathematically modeled using Castigliano's second principle. A sensitivity analysis was performed using these models to predict the sensitivity of each model to the parameters of design and manufacturing. The results of the sensitivity analysis were used in developing consistent manufacturing techniques and in choosing experimental equipment. Manufacturing techniques were developed to construct the actuators. Experiments were designed and performed to validate the manufacturing techniques and theoretical mathematical models. After the models were validated they were used in a parameter analysis to develop guidelines on how best to choose design parameters for a macroactuator. Utilizing these guidelines, a macroactuator design was developed that would meet the actuator requirements for an artificial hand.;This research is significant because it determines that an actuator, designed from polymeric piezoelectric materials can fulfill the need for an actuator in an artificial hand. In this research, the concept and design of a microactuator building block was introduced, that, when combined with many other replicate microactuators, forms much bigger and more robust actuators called macroactuators. The schemes for combinations provide wide flexibility in the design so that piezoelectric actuators may be used in a variety of applications. Mathematical models, manufacturing techniques and experimental verification methods were developed that can aid future designers using this microactuator building block concept.