Enhancing Haptic Fingertip Feedback via Pneumatic Actuators

In this work, we present the design and proof-of-concept for a soft pneumatic actuator that employs a pneumatic transmission to provide haptic feedback to four areas of the fingerpad. With this feedback, users can sense where force is applied on a remote palpation tool. The pneumatic actuator’s performance was evaluated through two preliminary experiments: one measuring force versus pressure and a second assessing participants’ ability to discriminate cues felt on different areas of their fingerpad through the device. Three participants were all able to identify which chamber was being activated with 100% accuracy at a pressure selected for easy identification; even at a second lower pressure, participants averaged 99.2% of chambers correctly identified, with a mean information transfer of 1.95 bits, indicating that it was very easy for participants to distinguish which part of their fingertip was being cued. This passive pneumatic feedback method has potential for applications in soft robotics, haptics, and medical robotics as its ability to provide force feedback could be leveraged in various fields requiring control.