Design and Fabrication of a Stretchable Circuit Board for Wireless Posture Measurement

We introduce a novel fabrication of a stretchable circuit based on a polydimethylsiloxane (PDMS) substrate for wireless posture measurement. To prevent the typical emergence of cracks attributed to thermal mismatch between the metal seed layer and the PDMS substrate, an intermittent process is proposed to deposit a metal seed layer directly on a PDMS substrate. Afterward, the resistance of the S-shape Cu-wire in the stretchable circuit was measured at different strain states. Results showed that the resistance of a Cu-wire within 55 mm $\times 0.2$ mm $\times 0.012$ mm increased not more than $0.060~\Omega $ at 30% strain from 0.735 $\Omega $ at zero strain. Finally, the wireless posture measurement system was verified through body posture experiments.