https://www.thetruthaboutcars.com/2017/ ... echnology/
If you have the freedom to redesign for an intuitive interface, I wonder what would be best? Reverse is usually only used zero or one time at the start, and again at the end of a drive (not often). If you are backing-up, you probably twist in your car seat (at least, I hope you're not relying 100% on the camera!). There could be a grab-handle to the right of the driver's seat, about where the parking brake is on some cars: when you twist around to look out the back window, grab the handle and squeeze a button to set the drive direction to reverse. This would simply produce a warning chime if the car is not already in Park. When reverse is actuated, for further confirmation, the car could play a "reverse" sound on the _inside_ of the car (you know... like your phone can play a separate sound for SMS messages from each of your kids?). A red LED on the dash could light; if the driver is looking forwards, it should be very hard to miss that the car is going to go backwards.