Design and Application of SMA Wires for Simulating Tactile Feedback in Bionic Fingers

This study aims to develop a biomimetic tactile sensing system based on shape
memory alloy (SMA) wire. By embedding a BMF75 SMA wire into a soft silicone “fat”
layer and covering it with a 1 mm-thick Dragon Skin 30 silicone “skin” layer, the
system is designed to mimic the structure of a human fingertip and respond to
vertical mechanical pressure through resistance changes. The SMA wire is driven by
a constant current diode set to 18 mA, and its voltage response is amplified using an
AD620 instrumentation amplifier module. A stable and distinct waveform
corresponding to applied force was successfully observed on the oscilloscope,
confirming the sensitivity of the system and the effectiveness of the structural design.
The current results demonstrate the potential of the system as a flexible bionic tactile
perception unit