Benjamin Tee1 Chao Wang3 Yu Jun Tan1 Yue Cao2 Wangwei Lee1

1, National University of Singapore, Singapore, , Singapore
3, Tsinghua University, Beijing, , China
2, University of California, Riverside, Riverside, California, United States

Electronic skins have witnessed tremendous interest and development over the last decade1. Functional soft, flexible and stretchable materials are crucial to the continued evolution of skin-like sensor applications in emerging soft robotics and novel human-machine interfaces. For example, ‘robots’ can don on sensor active skins to shake human hands with comfortable pressure and measure our health biometrics2. Here, I will discuss our recent work in achieving force-sensitive electronic skin technologies using soft polymeric materials. Bio-inspired digitization of analog signals have also enabled us to develop an artificial mechano-receptor that optically interfaces with neurons3. These technologies would be extremely applicable to advanced health technologies for neuroprosthetics and healthcare robotics.

Furthemore, recent developments in self-healing polymeric systems have propelled the exciting notion that electronic systems can repair themselves when damaged. One method to enable self-healing of damaged interfaces is via reversible hydrogen bonding4. However, one potential drawback of such systems is the significant reduction in healing efficiencies in the presence of a high humidity environment due to quenching of the surface hydroxyl groups by water molecules. I will also present some of our recent work on creating printable, humidity-robust self-healable polymer composites that could be useful for next generation, soft electronic sensor skins.

1. Hammock, M. L., Chortos, A., Tee, B. C. K., Tok, J. B. H. & Bao, Z. 25th Anniversary Article: The Evolution of Electronic Skin (E-Skin): A Brief History, Design Considerations, and Recent Progress. Adv. Mater. 25, 5997–6038 (2013).
2. Schwartz, G. et al. Flexible polymer transistors with high pressure sensitivity for application in electronic skin and health monitoring. Nature Communications 4, 1859–8 (2013).
3. Tee, B. C. K. et al. A skin-inspired organic digital mechanoreceptor. Science 350, 313–316 (2015).
4. Tee, B. C. K., Wang, C., Allen, R. & Bao, Z. An electrically and mechanically self-healing composite with pressure- and flexion-sensitive properties for electronic skin applications. 1–8 (2012). doi:10.1038/nnano.2012.192