A simple control strategy for increasing the soft bending actuator performance by using a pressure boost

Abstract

High-speed actuation of soft actuators requires high source pressure to transfer air as quickly as possible into the actuator. Allowing high source pressure and having the deformation angle as the only control input may allow faster actuation, but there is a risk of bursting when the actuator is prevented from reaching the desired angle, for example, due to an obstacle. The other option to control the actuator’s deformation is based on controlling the pressure. In this paper, we present a simple control strategy that uses an initial pressure boost in a pressure-based PID controller showing the same performance as in angle-based PID control. The performance improvement is demonstrated experimentally on a standard soft bending actuator and a gecko-inspired, climbing soft robot.