Virtual Switches and Indicators in Automotive Displays
Over the last decade, graphical and touch displays have become commonplace in automobile cockpits. Such displays have been used mainly for convenience functions such as navigation, radio, driver information, and vehicle settings. Automakers are now using these displays to generate “virtual” indicators that replace regulated and/or safety-critical physical indicators, such as gear position indication or the Malfunction Indicator Light [MIL]. Automakers are also replacing physical switches and controls, such as heating, ventilation, and air conditioning [HVAC] controls, with “virtual” controls rendered on the cockpit touch-screen. Many of these indicators and controls have regulatory and/or functional safety requirements that have been met using such methods as redundant terminals in a safety-critical switch, or by monitoring the electrical State-of-Health [SOH] of discrete LED indicators.