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Pulse width modulation as energy-saving strategy of shape memory alloy based smart soft composite actuator


This paper presents electrical power consumption decreased in actuating a shape memory alloy (SMA) based smart soft composite (SSC) actuator using pulse width modulation (PWM). A DC current input generator and a PWM signal generator were designed to apply inputs to SSCs. Experiments were carried out on two types of SSC: one conventional, using a single SMA wire, and the other using multiple wires. The blocking force was measured to analyze the performance of the SSC. The experiments demonstrated that the PWM signal was able to reduce the actuation energy while showing the same performance as an analog current input. These results suggest that a PWM signal could be an alternative candidate for the input paradigm for SSCs to reduce energy consumption, expanding the uses of SSC actuators in robotic applications.

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Correspondence to Sung-Hoon Ahn.

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Kim, M., Shin, YJ., Lee, JY. et al. Pulse width modulation as energy-saving strategy of shape memory alloy based smart soft composite actuator. Int. J. Precis. Eng. Manuf. 18, 895–901 (2017).

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  • Energy consumption
  • Pulse width modulation
  • Shape memory alloy
  • Smart soft composite