Microgripper driven by E-T(Electro-Thermal) actuator

E-T(Electro-Thermal) 액츄에이터를 이용한 microgripper

A microgripper driven by E-T (electro-thermal) actuators has been designed and fabricated by surface micromachining. This microgripper consists of two E-T actuators. Each actuator has two arms with different widths joined at the end to form a 'U' shape. The wider 'cold' arm has a narrow flexure at the end (anchor or electrode side) for easy bending, This actuator can be fabricated with only two masks - one for the sacrificial layer and the other for the poly-Si structure layer. An E-T actuator bends its arm due to unequal thermal expansion between the 'cold' arm and the 'hot' arm, This actuator tip moves laterally in an arcing motion towards the cold arm side when the structure is unevenly heated by the applied current. Therefore each microgripper is actuated inwards and can hold a micro object. The fabricated E-T actuator was operated in the range of $2{\sim}12V$ and $1{\sim}5mA$. and maximum tip displacement was $13.6{\mu}m$. This device may become useful in many applications because an E-T actuator can be designed and fabricated easily, and obtain large displacement.