Experimental Investigation and Empirical Analysis of a Shape-Memory-Alloy-Actuated Electromechanical Oscillator

Purpose This paper presents a design and implementation of a shape memory alloy actuated electromechanical oscillator. This is a non-magnetic high-deflection electromechanical oscillator, which is based on the concept of electro-thermo-mechanical actuation. The system can be used to produce an electromechanical oscillation of low-frequency and high-deflection with high-block force. Methods A prototype of the oscillator is developed using an elastic carbon-steel spring, a NiTiNol actuator, which serves as an SMA actuator, a rack and pinion gear assembly and an electronic logic circuit. The whole assembly functios in a closed loop with negative feedback. Results The developed prototype can produce a reciprocating rectilinear peak-to-peak mean deflection of 6 mm and reciprocating curvilinear peak-to-peak mean deflection of 19$(boolean AND)o$ at around 35 mHz frequency with 0.9 % mean duty cycle. The device is tested using a 12.4 V DC power supply at room temperature. Since, the mean duty cycle is extremely low, which is around 0.9 % for the developed prototype, hence, the power consumption of this system per cycle is considerably low around 0.4 W/cycle. Conclusion The Joule heating is the base of the proposed approach. Hence, the proposed system offers an advantage of getting operated by both DC/AC supply.The electromechanical motion, which is generated by the developed soft-actuator assembly, can be used in applications such as robotics and mechatronics. The developed mechanism can also be used to hold things very fast and place them slowly. The same mechanism can also be used to produce flapping motion with large block force, or hammering action with high impact force at low frequency. The proposed system, can also be used in slowly repetitive or non-repetitive (through customization) electro-mechanical lever-releasing mechanisms for fluid-valve on-off operation and jumping, throwing and triggering executions.