Reconfigurable Pneumatic Oscillatory Circuits

Electronic control hinders the applicability of soft robots for tasks in highly radiated environments, such as procedures that require intraoperative magnetic resonance imaging. Recent strategies have employed electronic-free fluidic circuits to create functionality in soft robots. However, these lack the level of controllability and reconfigurability achievable with classic electronically controlled systems. Here, we present adaptive pneumatic valves that widen the design space for electronic-free fluidic circuits. The valve is based on a mechanism that controls the kinking of soft silicone sleeves connecting two tubes. We show the influence of two parameters on the valve's operation pressures: the valve's actuator position and the cutting angle of the pneumatic tubes. We demonstrate that by controlling the valve's parameters we can obtain an array of responses from the fluidic oscillatory circuit. We prove this via two circuit configurations: a reconfigurable ring oscillator and a relaxation oscillator. Finally, we aim to showcase the advantages of these reconfigurable circuits in an MRI-compatible microfluidic device that controls the volume of drugs to dispense to a patient.