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Posted: Wed Jun 12, 2013 3:29 pm
by GameboyRMH
Sorry, no updates for now. The car that the RCP is going into is getting a major overhaul and that's been tying up my time & money. I think this project will get going later in the year.
I should add that another idea I've had for communications between the sensors and the RCP is a board that will multiplex the inputs based on a PWM signal from the RCP. Should work and tie up only two RCP pins if it can switch & read values fast enough - 1hz resolution is about the bare minimum I'd want.
Posted: Mon Nov 11, 2013 8:18 pm
by mrldcty
I REALLY want real time tire temp telemetry! Any updates?
Posted: Tue Nov 12, 2013 1:31 pm
by GameboyRMH
None yet...My car's gonna be done this month, I think I'll get started on this in December.
Posted: Thu Nov 14, 2013 3:31 pm
by MichaelDrost
As an alternative:
http://www.opti-grip.com/optigrip/Opti-Grip.html
I've bought them and they work! They're a bit chunky and were hard to fit in the wheel well of an e30 325i, but they were worth the price tag!
Simple sensor, connects via usb cable to a central unit, that outputs 0-5v per sensor, senses 260 degrees C max.
Michael
Posted: Thu Nov 14, 2013 3:53 pm
by GameboyRMH
Huh the price isn't too harsh on that, $450 for 3 sensors per tire...not cheap enough for me though
Posted: Fri Nov 15, 2013 3:26 am
by mrldcty
FYI, ran across this in my research:
http://www.honors.ufl.edu/apps/Thesis.aspx/Download/800
Contains source code in the appendix.
Not sure if a single I2C bus will handle all twelve sensors though? Puts sensor cost at around $50/corner.
Posted: Fri Nov 15, 2013 9:32 am
by andylaurence
That Opti-Grip system looks good, but it'll tie up 12 inputs. Is it possible to interface I2C sensors directly to the RCP? What form does the RJ-45 expansion port take?
Posted: Fri Nov 15, 2013 10:27 am
by neoraptor
RCP has 2 serial ports.
These sensors (Melexis MLX90614) outputs either I2C or PWM. So you would need to integrate a microcontroller to make the conversion and send it back to RCP.
On the RCP side, you will also need to write a code to record these channels.
The other solution is to use the system that outputs directly 0-5v signals and record them (but you will only be recording tyre temperature).
But I agree, this system looks really good.
Posted: Fri Nov 15, 2013 10:37 am
by andylaurence
Any ideas how to read the serial port with RCP? I think it's beyond me at the moment - I suspect it's a firmware thing as LUA isn't going to parse serial data fast enough, is it? OnTick only runs at 1Hz...
On a similar note, I've got a TTL serial output from my ECU, so being able to read that would be brilliant as it gives a stream of all my sensor detail at a high refresh rate. There's
a separate logger available, but I'd rather have it all in one unit so I don't have to combine CSV files and, most importantly, so I can buy the RCP Bluetooth adapter and analyse the logs between sessions on my phone/tablet.
Posted: Fri Nov 15, 2013 10:57 am
by neoraptor
I think it is plan to raise the script frequency to a custom value in a future firmware update (
http://www.autosportlabs.net/RaceCaptur ... ature_List).
Also, reading the data each second will not be a problem (and it might be enough for the tires).
There is a function to read the data from a serial port in Lua.
http://www.autosportlabs.net/RaceCaptur ... aScripting
If you know the format of your data, it should not be a problem to read them from RCP.
Posted: Wed Nov 20, 2013 2:55 am
by toga94m
Autosport Labs Facebook page posted info on this 8x8 thermal array sensor today, though it's been out for a year or more. Panasonic makes the sensor. Looks like they expect it to be a human body detector rather than a motorsport sensor. 60-degree field of view, up to 5 meters away.
$75 evaluation board, with USB output and PC software. Bare sensor module is about $40.
http://www.digikey.com/product-search/e ... grid%20eye
link to docs
http://eewiki.net/display/projects/Pana ... 0and%20GUI
Manufacturer promo video
http://www.youtube.com/watch?v=wOTOQfU5Qgw
tom
Posted: Wed Nov 20, 2013 1:10 pm
by dimondjack
This looks incredibly cool. 10 frames/second! That's a lot of data. Hopefully someone with more time can tinker up an interface between the dev board and the expansion port.
Posted: Wed Nov 20, 2013 10:52 pm
by mrldcty
Here is another array sensor option:
http://www.melexis.com/Infrared-Thermom ... 0-776.aspx
I was thinking, with an IR source on the upright (next to the tire) as a temp calibration and location reference, an array-type sensor could be mounted in a stationary location (e.g., body/frame), eliminating the need to mount the whole array on the upright. This would avoid the un-sprung weight, temperature/vibration proximity effects, and perhaps even sanctioning body regulation issues. hmmmm....
Posted: Sat Nov 23, 2013 4:00 am
by brentp
It looks like the melexis is the top contender for a non-contact sensor. We're discussing the possibility of taking this on as our next accessory / sensor project. hold tight -
Posted: Fri May 08, 2015 9:51 am
by russian
That's a cool one, order placed