An arc-shaped polyvinylidene fluoride/ionic polymer metal composite dynamic curvature sensor with contact detection and scanning ability

• Develop a 3D flexible dynamic curvature sensor with contact sensing functionality.
• The sensor is fabricated from a PVDF film and integrated into an IPMC actuator.
• Results show that more than 200% curvature change can be detected.
• The contact function is verified by a 20% voltage amplitude increase.
• The sensing mechanism can scan a range of 2.7 mm with the 5 mm long IPMC actuator.

This paper presents a novel flexible dynamic curvature sensor with contact sensing functionality. The sensor is fabricated from a piezoelectric polyvinylidene fluoride (PVDF) film and integrated into an actuator fabricated from an ionic polymer metal composite (IPMC), which allows the curvature/contact-detection of various curved targets in direct contact with the device, and the curvature-sensing mechanism can also perform a scanning motion by using the electrically controlled IPMC actuator. This polymer-based sensor can detect large curvature changes and can dynamically sense any variations in curvature as a function of time. Moreover, the embedded contact function of the curvature sensor can monitor whether the target contacts a specific point of the sensor. This text details the device design, working principle, fabrication process, and testing procedure. The results show that more than 200% curvature change can be detected based on the fabricated device with a curvature radius of 6 mm. The contact function is verified by a 20% voltage amplitude increase, and the sensing mechanism scans a range of 2.7 mm with the 5 mm long handle portion of the IPMC actuator driven by a voltage of 8 V. The developed device could be applied to a dexterous robot for monitoring the changes in shape of a substance, or to a catheter for medical applications.