Design and fabrication of electro-thermally activated micro gripper with large tip opening and holding force

This paper reports on the design, fabrication, and characterization of a distinctive MEMS gripper electro-thermally driven jointly by a new metallic V-shape actuator (VSA), and a set of modified Guckel U-shape actuators (mUSA). The modification of the angle between the hot and cold arms in the mUSA facilitates desired unidirectional in-plane displacement and thus increases the opening of the gripper. This unique configuration distinguishes this MEMS gripper from other similar devices in the capability of generation of larger tip displacement and greater holding force. Tip opening of ~173 μm and holding force of ~5 mN have been measured at a low operating voltage of 1 V with consuming power of 0.85 W. MetalMUMPs is employed to fabricate the device. Electroplated nickel is used as the structural material. The metallic structure allows a low operating voltage and low overall power consumption.