F1 Style RPM Light Bar

Projects General Guidance
1

Ok guys so I am a novice arduino user and I could really use some help. I'm trying to make an F1 style RPM Light Bar you see on F1 cars like this

I don't want the gear data, just RPM. Before you flame me for not searching, I have searched and I have found too many methods to count. A lot of them seem unreliable and I can't find any solid information. I'm a college student with limited resources so I can't really afford to just go around buying everything I see. Here's what I have:

  1. Arduino UNO
  2. A lot of wires, jumpers, and lcd screens
  3. A week of time to kill

I could buy an OBDII cable if I have to like the ELM-327 or even some other guys OBDII UART ADAPTER(Freematics OBD-II Adapter for Arduino | ArduinoDev.com), I just need to know if anyone here has any experience and can kind of guide me. I could make an enclosure for the lights and all I really need to do is create an rpm range and have the lights light up accordingly. Also how do you go about running an arduino in a car for permanent use? SO many questions, I'm just trying to stay on topic. YES I don't know what I'm doing that is why I have asked here. I have taken a few programming classes and I played around with all of my arduino starter kit programs, but this is on a whole different level. I feel like it could be easier than I'm making it out to be. Could I not just find some raw analog rpm data and feed it to the arduino or do I have to go through the OBDII? Thanks for all information and time! -David

2

Just the 15 LEDs?
Yes, you could smooth analog RPM data with a low pass filter, then light up the 15 LEDs sequentially based on the analog reading you get. 100 updates a second if you wanted too. Use high brightness LEDs at lower currents so they're bright but not IO power hogs.
I would not run an arduino in a car. A promini perhaps, with LEDs/current limit resistors and soldered connections to the board, and some decent power filtering (or a switching regulator even) to make 5V for the board from the vehicle 12-14V battery/power system.
Get an FTDI Basic or equivalent for programming it.

3

Thanks for the reply! Okay so say I get another board, how should I go about reading the analog data from the car? What option would be the best? Have you tried any of the OBD-specific boards out there?