EIT tactile perception system based on adaptive current excitation and conductive sponge

Abstract Electrical impedance tomography (EIT) technology has garnered extensive attention in the field of tactile perception for electronic skin owing to its non-invasiveness, low wiring complexity, and excellent flexible adaptability. However, in practical applications, flexible sensing materials are often subjected to complex and uncontrollable mechanical conditions such as stretching, compression, and local damage, which induce drastic fluctuations in load impedance. Meanwhile, the contact state at the electrode-material interface is prone to change, further increasing the uncertainty in the measurement process. Under such dynamic working conditions, traditional current excitation methods are susceptible to load modulation, thereby reducing the system’s measurement stability and introducing imaging errors. To address the aforementioned problems, this paper designs a constant-current excitation circuit based on closed-loop feedback. By monitoring and regulating the output state, the circuit achieves stable control of the injected current under complex variable impedance conditions. Compared with schemes that solely rely on high-performance devices or complex compensation networks, this method not only ensures basic measurement accuracy, but also strikes a balance between circuit implementation complexity and system stability. Experimental results demonstrate that the proposed excitation circuit can effectively improve the consistency of current injection, thereby enhancing the stability and reliability of EIT imaging results.