May 5th, 2008


Automatic Tripmeter

All cars have an odometer. Most of them also have a tripmeter. A tripmeter lets you see how much distance a given trip covers: you start it when you leave (resetting it to 0), and then you check it when you arrive to see how far you've gone.

Handy. In theory. But personally, I rarely remember to actually check the tripmeter when I arrive someplace. I'm generally too busy doing the stuff I actually went there to do. Sometimes, I don't even think to start it until after I'm partway there, at which point it's too late to even bother.

This is where my idea comes in: in addition to the regular one, a car could also have an automatic tripmeter. Every time you start the engine, it automatically restarts the counter and stores the previous value in memory. It could easily keep several (or more than several) previous trips in non-volatile memory, since a single 16-bit integer would be plenty for each one (unless you plan to go more than 6553.6 miles without stopping to rest). Push the button, and it shows you the distance of the previous trip. Push it again, and it shows the trip before that, and so on. Don't touch the button for a minute and it goes back to showing the current trip.

Does it already exist? Or am I the only one who could use something like this?