Dynamic single-input control of multi-state multi-transition soft robotic actuator

TL;DR

This paper introduces a novel single-input control method for multi-state soft robotic actuators using interconnected bi-stable elements, enabling complex multi-state transitions with minimal actuation.

Contribution

The work presents a new control approach for soft robots that simplifies actuation by exploiting dynamic responses and pre-designed equilibrium states in interconnected bi-stable elements.

Findings

Achieved up to 48 state transitions in a four-element actuator.

Demonstrated experimental validation of single-input control.

Formulated and analyzed the system's dynamics and stability.

Abstract

Soft robotics is an attractive and rapidly emerging field, in which actuation is coupled with the elastic response of the robot's structure to achieve complex deformation patterns. A crucial challenge is the need for multiple control inputs, which adds significant complication to the system. We propose a novel concept of single-input control of an actuator composed of interconnected bi-stable elements. Dynamic response of the actuator and pre-designed differences between the elements are exploited to facilitate any desired multi-state transition, using a single dynamic input. We show formulation and analysis of the control system's dynamics and pre-design of its multiple equilibrium states, as well as their stability. Then we fabricate and demonstrate experimentally on single-input control of two- and four-element actuators, where the latter can achieve transitions between up to 48 desired states. Our work paves the way for next-generation soft robotic actuators with minimal actuation and maximal dexterity.