Design and Fabrication of a Novel SMA Spring Actuated 2DOF Orientating Mechanism

This paper presents design and fabrication of a new 2DOFfriction-locked mechanism which is actuated by shapememory alloy (SMA) springs. The proposed mechanismcan be used in car side-mirrors. It is also a good choice fortiling 3D surfaces like solar furnaces. The system containsan unprecedented friction-locking mechanism to eliminateits dependency on power when a desired orientation is obtained.Moreover, due to unique features of SMA springsi.e. high output force to weight ratio as well as low powerconsumption and price compared to conventional DC motors,SMA springs are chosen to actuate the system. A prototypeof the mechanism is fabricated in order to experimentallyevaluate its functionality. Test results show thatshape memory springs successfully manipulate the top plateto a desired position. In addition, when system reaches favorableposition and input power is cut off, it successfullysubsists on its state without power input.