Tire inflation system

A few months ago I had an idea of inflating/deflating left and right tires at the same time. I made a manual device with a few valves and it worked quite well. Then I thought, wouldn't it be nice to be able to electronically control that with preset pressures? How difficult could that be? (Just to be clear, this is not a central tire inflation system that supply air through the axle like the Hummer or big trucks. This system just hooks to the tire valve stems and can only work while the wheels are not moving) The answer was quite difficult. Our wonderful minds can easily comprehend when to check the tire pressure, estimate how long to let the air out and check again, then by judging the new pressure, how much air to let out and check again. Our minds can make those decisions in one second.

Well, to program that, it took my slow-moving mind on and off for 3 months to complete this project. I used an Arduino to control 1 input and 1 output valve. The manifold has 2 outlets connecting to the tire valve stems. The temperature under the hook can go up to 190F, so I kept the controller in a portable enclosure. I kept the relays for the solenoids and voltage regulator close to the all the air couplers and hardware. The LR4 doesn't have a lot of empty space to mount these stuff, the only open spot is on the passenger side in front of the air filter. There is only one large hole going into the wheel well, so I made a through-bolt and mounted an aluminum U bracket to it and another L bracket to connect all the stuff. The air comes from the on-board Viair pump I installed on the driver side behind the air filter. I thought about connecting another air line to near the towing point inside the rear bumper, but I didn't want to unscrew the 2 plastic taps and remove the center plastic cover each time I need to use this. It turns out to be more work than just carry longer hoses for the rear tires. All these were done with simple hand tools and a drill press.

The controller has 2 pressure presets and 1 adhoc setting for inflating and deflating. It also attempts to estimate how long it takes to inflate the tires with these parameters through another menu setting: tire width, tire profile, wheel diameter, wheel width, number of tires, air source CFM. This is still a wild guess calculation and I am still testing that out. I can get the pressure to between 0-1.5 psi of my target pressure.

Now this is done, I don't know if it is practical for real trail use, but it was a fun project. Now on to other crazy ideas....

Very cool!

wow that is really something...props to you buddy!

Really interesting. You got a video of it working?

Well, here is a short 3-minute demo video of the system.

https://drive.google.com/open?id=1CsauaEOgj_UklpMTYCA-ZpIeF4_WrdxX

Very cool indeed. Can we get a look at your air compressor too?

jlmoped said:

Well, here is a short 3-minute demo video of the system.

https://drive.google.com/open?id=1CsauaEOgj_UklpMTYCA-ZpIeF4_WrdxX

Click to expand...

Wow. That's awesome.

Very impressive. Fun stuff.

Here are some photos of the on-board compressor.

LR3 has a lot of room on the driver side, but the LR4 has a lot more stuff crowded in that space, so I had to make a backplate and 4 standoffs to clear the circuit board bracket and wire harness. After installing everything, I was told it wasn't a good idea to have free standing copper tubing for the air coupler, so I will fix that some day. Since now I have the inflation system with a permanent connection to the compressor, I don't really need a separate air coupler, I might just remote the copper tubing and connect an air coupler directly to the manifold.

That is Sweet if it could fit two versions

1. a pelican case with compressor, 2/4 port inside with storage space for the airlines with cigarette lighter cable to power it or crock clips
2. the same as 1 but have a lithium battery to power with a charging port drilled into the case.


Have the computer in the lid you could really make some money with that.