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does any 1 know how to make a sensor to detect cornering in a car and road moisture? Answered

im thinking an Infared diode that reflects on the road into an infared phototransistor for the road mositure (water) sensor. ( i have one problem with this its going to be placed under a car how will it keep clean?) i guess i just gotta to find a good spot.
Also for the cornering sensor ( more like a G sensor but it has to be sensitive.) how will it be sensitive enough ?
Its for a justy 4wd traction control system im thinking off
( note to all justy enthusiast i dont have it yet)


Maybe you could use an inertia sensor, gyroscope, or accelerometer for the cornering...

thank you guys but i guess this isnt going to work because the subaru justy doesnt have a center differential, and with the system i discribed it would probally kill me or the car ( too many factors to consider). the switching from the 2wd to 4wd would also need a clutch or center differential for it to work effectively. If i do try to tempt this the car would need a complete overhaul, when i could just buy a car with full time awd or take out the front drive axles :')


6 years ago

Try an accelerometer IC (ofttimes available from Digi-Key, Electronic Goldmine or the like) for the g-force sensor. I understand some of these ICs require very few external biasing components. The moisture sensor is a fairly simple circuit to build, just look in the IC "cookbooks" by Forrest Mims (available from Radio Shack and online).

Good luck, and "Drive Safe!"

I don't think you could do it that way. You already suggested a concern with keeping it clean, what would happen if you went through mud, or snow? I assure you, my car, after going through a mountain pass, is completely transformed in color (due to all the sand and salt they put on the road).

The way I understand it, you're looking for a Traction Control System, which exists already in many vehicles (including mine). The way it works is by adjusting the traction from tires that slip to tires that grip. (I'm sure its more scientific then that).

How you'd make one yourself probably requires an engineering degree. (Just guessing). I'm sure someone else here will clarify if I am wrong.

heres the case im starting an bsc electronics @ university, although im still in prelim i still know a little bit on how to get the sensors to work and so on. the problem lie with the justy`s build its a part time 4 wheel drive and the offline drive is the front drive axle. Its a selectable switch all i have to do is get the sensors readings and use a couple gates (logic), or decoder to get it turned on at the specific time. My original plan was this to remove the 4wd switch and put in a rain sensor to turn on the 4wd seeing that it isnt sensible to turn it on tarmac, then i thought to myself what happens when i get into mud? Or lose traction on the road so i guess its a bit complicated. Then i thought well if part time 4wd only has problems when cornering why not just use g sensors to dectect cornering and switch it off when necessary, and neglect this when the road is wet ( where the necessary slip is available)

After doing some reading, I think you are actually on the right track. The use of an infrared light is similar to "Rain Sensing Wipers", where the light is projected onto the windshield at an angle to read the amount of light that is reflected back.

Obviously the design would have to account for a variety of conditions to still operate in the snow and perhaps dirty and muddy situations. Perhaps with some research you could find out how they overcame these challenges to make the system work for you.

For the cornering sensor, couldn't you just create a system based on the turning radius of the steering components? I looked online and there is some interesting information about an "InteliSteer" System used in farming that might spark some ideas for you.

I don't see how you can detect moisture - general reflectivity?
How about a laser* instead?


*better range


6 years ago

The best approach would be to have the sensor in the road and not the machine traveling on it. Possibly in the future they will embed RFID chips into the road surface that can tell your car things like temperature and moisture levels and it could then use that data to make adjustments but at this time its eyes that do that work.

TCS rely on wheel spin/position sensors, rather than looking at the road surface.