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Splendor of Fluids in Motion | Microtechnology

Microtechnology

The two photographs below appeared in The MEMS Handbook, edited by Mohamed Gad-el-Hak, published by CRC Press (2002), second edition in three volumes published by CRC Taylor & Francis (2006). Directly below is the first walking microrobot with a Swedish wasp relishing a ride on its back. The out-of-plane rotation of the eight legs is obtained by thermal shrinkage of polyimide in V-grooves (PVG). Leg movements are effected by sending heating pulses via integrated heaters causing the polyimide joints to expand. The size of the silicon legs is 1000x600x30 microns, and the overall chip size of the robot is 15x5x0.5 mm. The walking speed is 6 mm/s and the robot can carry 50 times its own weight. Photograph by Per Westergard, Vetenskapsjournalisterna, Sweden, courtesy of Thorbjorn Ebefors, Royal Institute of Technology, Sweden.

tiny robot with bee

The second picture is a scanning electron micrograph of a 12-layer microchain fabricated in nickel using the Electrochemical Fabrication (EFAB) technology. Overall height of the chain is around 100 microns and the width of a chain link is about 290 microns. All horizontal links are free to move, while the vertical links are attached to the substrate. By simply including a sacrificial layer beneath the links, the entire chain can be released from the substrate. The microchain is fabricated in a pre-assembled state, without the need for actual assembly. The beast towering over the microchain is a humble, picnic-loving ant.

bee

Photograph courtesy of Adam L. Cohen, MEMGen Corporation, U.S.A.