While the traditional, "open road" cruise control continues to be
useful, long drives this past weekend got me thinking about how much
I'd like to have an "in traffic" cruise control.
That is, in addition to "maintain this speed", which is only useful
if there's either nobody in front of you or there's plenty of room
for smooth lane changes as needed to avoid crawling up someone else's
tailpipe, I'd like to be able to tell the car, "maintain a following
distance of [minimum safe distance + user-specified comfort buffer]
seconds from whatever's in front of me".
Such a cruise control would probably need to be linked to the
brakes, not just the throttle, and even with the ability to brake
it might be good to have a warning tone sound when the car in front
decelerates at an unusual rate. (And just as with traditional cruise
control, the idea would be simply to make driving a wee bit easier,
not to lull the driver into no longer Paying Attention, since what
I'm describing is still short of an autopilot.) Additional tweaks
to the algorithm would include setting a maximum speed, which would
double as the speed setting for reverting to traditional cruise
control when there's no vehicle in sensor range, and detecting
lane changes (as momentary override plus acquisition of a new sensor
target).
This is the front-bumper parallel to what I've wanted on the
back of my car for a while now: a rangefinder coupled to my
spedometer which would light up a "You Are Too Close" sign whenever
someone tailgates me.