Development of SMA-Actuated Microgripper in Micro Assembly Applications

Self-Biased-SMA Drive PU Microgripper with Force Sensing in Visual Servo

“…A SB-SMA actuator has been developed and employed for actuating microgrippers in gripping and assembly applications [20]. For the SB-SMA actuator employed, the actuator was manufactured mainly by the following procedure.…”

“…In considering the requirements of miniaturization, a self-biased SMA actuator which does not use an additional bias spring or antagonism is most applicable [33]. Although several SMA-actuating microgrippers have been developed, very little research has been undertaken on utilizing selfbiased-SMA (SB-SMA) actuators [20,[27][28].…”

“…There were several different designs of SMA-actuating microgripper developed for micro manipulation. Chang et al [20] developed a PU microgripper actuated by an arc-shape SMA-wire actuator. The actuator has residual stress from bending the wire to act as a bias spring.…”

“…In a literature survey, the fabrication material for polymer microgrippers was found to mainly include SU-8 [13,[16][17][18][22][23][24][25] and Polyurethane (PU) [14,[19][20][21][26][27][28]. The actuators employed include laser-powered [12], pneumatic [13], piezoelectric [14,19,23,26], SMA [16,[20][21][27][28] and thermal-heating [17-18, 22, 24-25] drive actuators.…”

“…In the recent years, due to the advantages of material compatibility, production cost and the mechanical properties of applications, the progress of polymer microgrippers has gained notice [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28]. In a literature survey, the fabrication material for polymer microgrippers was found to mainly include SU-8 [13,[16][17][18][22][23][24][25] and Polyurethane (PU) [14,[19][20][21][26][27][28]. The actuators employed include laser-powered [12], pneumatic [13], piezoelectric [14,19,23,26], SMA [16,[20][21][27][28] and thermal-heating [17-18, 22, 24-25] drive actuators.…”