Towards Soft, Printed Circuits and Sensors for Soft Robotic Applications
Abstract: The popularity of soft robots and soft wearable devices has led to a need for effective monitoring of strain, pressure, and electro-physiological signals. However, the integration of traditional circuits and sensing methods has proven to be challenging, with researchers resorting to selective rigidisation of sections of the soft robot or wearable to house circuitry. This affects both the functionality of the soft robot and the comfort of the wearable. Furthermore, the number of wires required to acquire data from traditional sensors severely limits the achievable sensor density.
To address these issues, we propose a suite of soft, printed sensors along with fully stretchable circuits to replace traditional sensor systems. We deploy a variety of additive manufacturing methods including screen printing, direct ink write (DIW), stencil printing, and casting to fabricate- (i) circuits with traditional surface mount ICs and passives, fine traces and pitch (10mil – 250μm each) that are able to stretch up to 225%; (ii) soft strain sensors with high range and linearity, and low hysteresis and drift; (iii) high response, linear, soft pressure sensors, and (iv) low impedance electrodes for electro-physiological signal collection. We present results of each of these systems functioning independently.
We aim to combine all of this to make a data capture glove with fully printed stretchable circuitry that would be comfortable for prolonged usage. The glove would be able to capture finger flexion (MCP & PIP), pressure on the palm, and EMG signals from the upper and lower arm. These sensors and electrodes would be read out by a printed stretchable circuit that incorporates conventional surface mount ICs and passives. The data from the sensors would be wirelessly transmitted to a computer or other device for AR or teleoperation applications.
Advisor: Professor Pratap Rao
Committee: Professor Loris Fichera, Professor Cagdas Onal