Improved Autothrottle

I often find myself spending an inordinate amount of time watching my speedometer rather than the road - usually due to unreasonably low speed limits and a car quite capable of comfortably cruising at 160 km/h.

What I propose is a new function added to the autothrottle that most cars already posses:

When the desired maximum speed is reached, the user taps the cruise-control 'set' button to program the system, the only difference between a conventional cruise control being the mode the autothrottle is in. In this case it would be in 'never exceed this speed' mode, rather than 'hold this speed'.

Under this mode, the user could drive around without concern for exceeding the artificial self-imposed speed limit, therefore spending more time watching the road and less stress worrying about speeding. Of course downhill sections will still require braking of some sort, but braking will not disengage the autothrottle - in fact, below the set-limit, the improved autothrottle functions transparently.

Note: This system is primarily intended for vehicles of the 'drive by wire' type, due to the simplicity of implementation. Also, the system can be disengaged manually by switching off the cruise control, or by making an unusually deep/rapid throttle request.

(p.s. this is my first posting from a mobile phone - yeeehaw!)