Additive Manufacturing of Soft Pressure Sensors on a Non-Planar Surface
This talk will introduce an additive manufacturing process and polymeric materials to realize artificial sense of touch by manufacturing tactile sensors. The process combines direct-ink writing and rheology-controlled formulations. These formulations include a prepolymer including ionic liquids for a pressure-sensitive component and a carbon nanotube-based composite material for signal transmission. The sensor is additively manufactured, where the pressure sensitive layer is sandwiched between two electrode layers, forming a sensing element called “taxel.” Changes in voltage due to sensor deformation are signal processed to detect applied forces. The process and materials have been advanced to create tactile sensors on a freeform surface (i.e., nonplanar surface), where the process is named conformal additive manufacturing. In this process, a polymeric material is printed layer by layer by considering varying surface angles, where a series of algorithms such as boundary detection, freeform slicing, and tool path generation has been developed. Examples of 3D printed structures and sensors fabricated on a freeform surface will be introduced. In addition, sensor applications for robotics, tires, and insoles will be presented.
Jae-Won Choi is a Professor in the Department of Mechanical Engineering and Site Director of NSF I/UCRC Center for Tire Research (CenTiRe) at The University of Akron (UA). Prior to joining the UA faculty member, he spent one year for his Post-Doctoral research in the W.M. Keck Center for 3D Innovation at the University of Texas at El Paso (UTEP) in 2007, sponsored by the Overseas Post-Doctoral Fellowship from the Korea Research Foundations. After his involvement, he continued 3D printing research with the rank of Research Specialist in 2008, and Research Assistant Professor in 2009. He has secured ~$3.5M in research funding, published 50+ peer-reviewed journal articles and seven registered patents. His research interests include additive manufacturing, 3D printed smart structures including sensors, actuators and electronics, 3D printed rubbers, and 3D printable binder-coated metal/ceramic composites. He is currently serving as an associate editor in the journal – Additive Manufacturing; editor in The Korean Society of Manufacturing Process Engineers, editorial board member in International Journal of Precision Engineering and Manufacturing – Green Technology. He received the B.S., M.S. and Ph.D. degrees in Mechanical Engineering from Pusan National University, Busan, Korea, in 1999, 2001, and 2007, respectively.