I [somewhat] recently installed a short-ratio transmission in my vehicle and, after 11 years of ownership, I find myself often forgetting what gear I’m in. (I.e., going for an upshift when I’m already in 5th, not knowing if I’m in 3rd or 4th without looking/touching the shift knob position) In order to minimize distractions and keep my eyes on the road I decided to build a gear indicator.
There are a few indicators on the market, but they’re either too big/bulky, expensive, or are designed for sequential transmissions.
I’m using an Arduino Uno as a base. The indicator is an Adafruit 16-segment display. My issue lies in the switching device. My unimaginative idea is to utilize 4 lever-style micro switches, arranged in a square around the shift lever underneath the shift boot. This will allow the shift lever to depress 1-2 switches at a time, providing input to the Arduino, which will then determine which gear to display. The indicator will display “N” when the lever is in neutral and no switches are depressed.
It was suggested by a colleague that I use the engine speed and vehicle speed, and determine the ratio for each gear. Then this ratio can be used by the Arduino to determine the chosen gear. I suppose the reverse and neutral position switches in the transmission could then also be used as inputs, if necessary. Does the Arduino Uno have the ability to process the VSS & RPM inputs to determine a ratio? If so, what formula would I utilize for this?