Miniaturized Pneumatic Actuator Array for Multipoint Deep Pressure Tactile Stimulation

TL;DR

This paper introduces a simple fabrication method for small, wearable pneumatic actuator arrays from textiles capable of exerting deep pressure forces, suitable for fingertip tactile stimulation and multi-point stimuli.

Contribution

A novel, scalable fabrication process for textile-based pneumatic actuator arrays that can produce significant forces at small scales without complex assembly.

Findings

Actuators exert 2.1 N at 230 kPa pressure.

Array can include actuators as small as 8 mm in diameter.

Demonstrated multi-point tactile stimulation with combined stimuli.

Abstract

Wearable distributed tactile devices aim to provide multipoint touch stimuli, but struggle to provide sufficient forces (> 1 N) at frequencies to invoke deep pressure sensation with minimal encumbrance at small scales. This work presents a method of fabricating arrays of pneumatic actuators from thermoplastic-coated textiles. By routing pneumatic inlets to a common fold line in the fabric, we demonstrate that multiple pneumatic pouch actuators can be formed in a single simple heat-pressing operation that does not require the use of sacrificial blocking layers. The method accommodates a range of actuator diameters and spacing distances, including as compact as 8 mm diameter actuators spaced 1 mm apart, which enables use in fingertip wearable devices. In a blocked force test, these small pneumatic textile actuators exert 2.1 N when pressurized to 230 kPa. With this pair of actuators, we demonstrate an example application in which we invoke both distinct and summative stimuli, suggesting the possibility of titrating just noticeable difference in amplitude with a textile actuator array.