A force sensor based on reverse effect of magnetically controlled shape memory alloy

Magnetically controlled shape memory alloy (MSMA) is a class of smart materials that changes shape when it is exposed to a moderate magnetic field, which provides a new way to produce motion and force. On the other hand, the MSMA material can change its magnetic property when it is subjected to external force, which is known as the reverse effect of MSMA. A force sensor based on the reverse effect of MSMA is proposed in this paper. Variation mechanism, relationship of magnetic flux density versus strain and the relative permeability character of MSMA material are analyzed. The static and dynamic experimental results of the sensor prototype show the larger variation of magnetic flux density and the induced voltage are generated in the force sensor, the feasibility of the design method of the proposed MSMA force sensor is proved.