Stretchable electronic skin patch with strain isolation for the simultaneous measurements of surface electromyography and temperature

Abstract Stretchable electronic skin patches have continuously attracted the attention of researchers and clinicians due to their potentials in medical applications. Despite the remarkable progress of electronic skin patches with diverse sensor modalities for regions undergoing small deformations, the electronic skin patch in a stretchable format for regions requiring large strain accommodations has far less been explored. Here, we report a stretchable electronic skin patch with strain isolation for the simultaneous measurement of surface electromyography (sEMG) and temperature. The electronic skin patch consists of two mesh-like sEMG electrodes and one resistance temperature sensor on a compliant substrate with programmable stiffness induced by the spatioselective ultraviolet exposure. This construct allows for mechanical softness of electrodes for an intimate attachment to skin and isolation of deformation-induced disturbances and damages to the temperature sensor. Experimental and numerical studies reveal the design, fabrication and operation of the skin patch. Demonstration of the skin patch with strain isolation on the lumbar muscle groups during the trunk flexion, which may introduce a 20% strain level, illustrates its robust capabilities for the comprehensive assessment of muscle activities with possibilities to study the temperature effect on sEMG signals. The results reported here provide important inspiration for constructing multifunctional electronic skin patches with a wide range of applications such as health-monitoring devices, wearable human-machine interface and clinical muscle function evaluation.