Theoretical thermal-mechanical modelling and experimental validation of a novel 3D three-fingered electrothermal microgripper

This paper compared the static theoretical modelling, numerical simulation, and experimental results of a 3D electro-thermal actuator that is built by three fingers. Each finger is composed of a U-shaped (two DOFs) and a V-shaped (one DOF) electrothermal actuator for three DOFs. The heating source of those actuators is from poly-imide films that is attaching with those beam actuators. When voltage or current (Joule heating) is applied to the polyimide film, the temperature of the beam increases since the thermal energy is transmitted from the film to the beam actuator. Then, the beam elongates due to the thermal expansion of the metal, resulting in displace-ment of the beam. In addition, we also perform the parameter analysis to discuss the effect of parameter change on the output displacement of actuator. Finally, the 3D electrothermal microgripper is used to implement micromanipulation experiments such as picking, moving and rotating on micro balls and zebrafish embryos in 3D space to verify its usability.