3-D Surface-Integrated Touch-Sensor System for Automotive HMI Applications

In the automotive industry, control panels and décor elements are designed as separate components which are geometrically and discretely combined. This considerably limits the technical variations of the design and the compactness of the construction. In this paper, the fusion of the control panel and the decorative surface to create a functional 3-D surface is presented. The approach is based on the integration of a touch sensor-based control and sensor module into a free-form decorative surface. For this purpose, an automotive-suitable touch sensor foil is used, made by silver paste screen printing technology. This highly sensitive touch sensor, which immediately reacts to the user's touch by a visible feedback, creates an impression of excellent quality. The integration of this sensor module into the decorative surface combined with display elements is done by an innovative connection concept. Herewith, the limits of the decorative surface are compensated for and the touch sensor performances, as well as the transmittance properties, are reproducible and robust. The sensor module has a local interconnect network-bus interface and meets the automotive requirements.