I want to create an existing technology which is TPMS. But I want to do it myself. Can anyone tell me if I can use arduino uno and communicate with the pressure & temperature sensors and get the output to my LCD display which attached to my arduino?
Can anyone advise me on this matter as I am lack of understanding.
rkosharil:
I am not sure. Is there any pressure and temperature seensor out there that can work with arduino?
There are many pressure and temperature sensors that will connect to an Arduino. What good will that do you when the pressure and temperature you want to measure are inside a tire and the Arduino and display are outside the tire?
Yes, that is what I want. The sensors are in the tyre and transmit the data to arduino (which have LCD Display attached to it). Arduino is the receiver. You know which sensor that can communicate with arduino?
Is there any pressure and temperature seensor out there that can work with arduino?
Oh, they are everywhere. The first issue you'll have, though, will be finding a pressure sensor that has an adequate range. Barometric pressure sensors (which often incorporate temperature sensors) could get the job done, but considering the pressures you want to monitor, it may be tough to find one that can sense the higher pressures you need.
A sensor like Sparkfun's MPL115A1 Barometric Pressure Sensor - MPL115A1 - SEN-09602 - SparkFun Electronics can sense pressures up to 115 kPa. That sounds like a lot, but when you convert that to PSI (1 PSI = ~6.89475729 kPa) you'll find that you're cap is around 16.6 PSI, not nearly adequate for a tire that's rated ~32-38 PSI. But keep searching, I'm sure someone knows of a product that does what you're after.
Once you find a suitable pressure sensor, though, setting up an RF link between all 4 tires and a central "hub" in the cabin of the vehicle shouldn't be too tough. You can have each tire transmit a reading periodically on some pseudo-random interval.
The guts inside your tire only need to consist of a battery, transmitter, sensor, and barebones arduino. In the cabin, you'll probably want a full size board, receiver, lcd and dc converter so you can run off the car's 12v supply.
That reminds me of my trying to figure out how my 2000 Buick knew how to warn me when I had a low tire.
After I had the car some months one morning when starting out the alphanumeric display showed a check tire pressure warning. So I looked and one tire was just a little lower then the other three so I pumped it up at a gas station and didn't think anything more about it. About a year later I was getting some new tires installed and I thought I would look at the dismounted wheel to see where the air pressure sensor might be mounted. Couldn't find a thing, just a plain old steel wheel, nothing mounted in it at all. So later I got on the Internet and started to research how it could sense a low tire warning without having pressure sensors on the wheel.
Turns out they don't use pressure measurements at all. Rather as each wheel brake assembly already has a speed pick-up sensor to support the anti-lock brake function they just use that same sensor to read each wheel rotation speed and then compare all four wheel speeds to see how close they are, and if one (or more?) is too much different then the others then it issues the check tire pressure warning. I thought that was pretty cleaver to come up with an additional monitoring function without needing any extra hardware, just added software.
retrolefty:
Turns out they don't use pressure measurements at all.
Some do. Some TPMS's (VW, Porsche, BMW, Saab) use a wheel-mounted or valve-stem-mounted pressure transmitter. Some use 315 MHz (US). Some use 433 MHz (Europe?).
retrolefty:
Turns out they don't use pressure measurements at all.
Some do. Some TPMS's (VW, Porsche, BMW, Saab) use a wheel-mounted or valve-stem-mounted pressure transmitter. Some use 315 MHz (US). Some use 433 MHz (Europe?).
Yes, my research showed several different methods being used, some using real wheel tire pressure sensors being used. My car just uses a simple method that just uses existing sensors and as such doesn't tell me which wheel is low (or too high I guess) but I was impressed none the less.
The first presents the complete protocoll from a generic sensor and the second gives a damn lot of information about TPMS systems in general.
Sadly for you the articles are both in my motherlanguage "german", but I decided to post them anyway, because the information is really exactly what one would need.
An ultrasonic sensor can be used to measure rotation speeds of individual wheels. Going by the basic premise that when air pressure in the tyre is low, the wheel rotates slowly, it can be found out which ones need refill or if one is too low.
(Does the latency of ultrasonic system permit its use in measuring speed?)
It might be possible to calibrate so as to get close-to-actual pressure readings also.
In addition, for temperature, an infrared temperature sensor can be used.
This arrangement can be good enough for normal use.
Just a head's up. The last time I bought tires for my Jetta, I was warned since the vehicle was equipped with tire pressure warning system, I had to always have wheels that support that. So, if you add this to your car, you may not remove it.
It's not the tires that support it, it's the $100/wheel sensor that goes on in place of the valve stem I believe.
My BMW came with them, when I had snow tires/rim put on at TownFair tire they asked if I wanted the TMP sensor - I passed on that, and now a low pressure light on the dash until I put other tires back on in the spring.
A few years ago, i purchased an aftermarket kit (Tyre Dog) to save tyre $$$.
it was cheap enough (under $100), and has saved its price several times over.
(New tyres at $500 each!)
it reports pressure and temp from 4x valve mounted transducers(each with a coin cell) - to a small unit inside the car (3x AA)
You could then study what they’ve done. I’d guess a low cost 433 transmitter something like the Hope or Nordic RF families.
rohit1979:
So, it is theoretically possible to measure tyre pressure using the wheel rotation speed. That should do away with the need for expensive sensors.
Yes. Not, an not theoretically, if you do the front wheels, they must be pointed straight ahead, otherwise the wheel on the outside of the turn goes faster than the inside wheel.