Car reverse backing obstacle sensor with sonic ranger

Who's talking now lefty? XD

Front side:

Back side:

Original box:

Who's talking now lefty?

You talking to me, you talking to meeeeee ? :smiley:

Cool. Now work on that sound, it should be a nice soothing low frequency gentle gong gong gong, picking up tempo. Yours sounds worst then my wife's shrill warnings for me not to back up to close to something. :wink:

Lefty

You mean increasing pitch as the obstacles get closer? Just several more variables I can put in my parameter menu! I have length of beep, length of silence, audio alert on/off in there already.Now I can add pitch, pitch ramp rate, and ramp pitch on/off. It's rather nice to have a parameter menu so I didn't have to re-upload if I don't like the way the pitch ramps.

BTW, that black box was made from a $1 3X5 card holder. It was black plastic sheets. I tore it down to make a face plate for my other project:

This picture was taken with a black paper face plate before I made the plastic one.

I just used a blade to cut on one side not so deep and fold at the cut. Then I spent a few minutes with my hot melt glue gun. There were also three sheets of cardboard behind the sensor to hold it in place.

the shield is arduino uno compatible?

ps: you got MP :grin:

The shield is compatible with arduino UNO, Duemilanove, MEGA and all arduino clones that are pin compatible with all that were just mentioned. 8) :smiley:

I think that I am going to copy this project a bit, I already have an arduino in my trunk connected to ignition, and a nice monitor in the front (for alternative clock and temperature sensors):


adding a ping or something would be interesting!
Fede

Alright! I suggest you got get two sonic rangers. Since I've installed my sensor, I've grown an additional sense: every time I drive, I look at the rear bumper covers of the cars in front of me. I've seen cars with 2 or 4 sensors spread around the bumper evenly. I think you will want wide angular response as well but mine was narrow so it measures more or less things directly in front of it and not so much for things on its side. Having at least two will be much better than one. You can use your display to show two bars, one for distance to obstacle on each side.

I'd like to do some test, I have here 2 types of sonic sensor... A parallax ping and a cheaper i2c SRF02. Probably I will wait for warmer days, as here in Italy for our standars :slight_smile: it's still cold :slight_smile: I like your project a lot!

Thanks Federico. It looks like you're already modding your car. Have you posted your project on Exhibitions yet?

This project is now a featured project on instructables.com 8)

I just posted it last night. I guess arduino + car is a big hit! :smiley:

nice work
you might want to make the tone go continuous once you get below a certain distance (12" maybe)
or have a LED come on?

Ok, then on to your next auto project. How about a arduino low tire pressure alarm? My 11 year old Buick has one built in, tells me to check tire pressure.

Lefty

retrolefty:
Ok, then on to your next auto project. How about a arduino low tire pressure alarm? My 11 year old Buick has one built in, tells me to check tire pressure.

Lefty

I'd like that too! I don't have a pressure gauge. The cheap ones all fell apart on me. How do you sense pressure? I know pressure capsules with voltage output but how do you do that on a rotating part? Now i have an idea. Put my persistence of vision display on my wheel so the dude driving next to me can honk me if he sees the message: "This dude needs more air on this tire!" XD

mmcp42: I can certainly do that. It won't help me backing blindfolded though! :grin:

I'd like that too! I don't have a pressure gauge. The cheap ones all fell apart on me. How do you sense pressure? I know pressure capsules with voltage output but how do you do that on a rotating part? Now i have an idea. Put my persistence of vision display on my wheel so the dude driving next to me can honk me if he sees the message: "This dude needs more air on this tire!"

This will be fun. I will only give you hints and additional hints if asked. The Buick has NO pressure sensors used to determine the low pressure warning. Also it does not tell me which tire is low, just that one needs attention. So how might you think it can determine that?

Lefty

I'm guessing:
a) level sensor, if one side is low chances are the tyre (sp) is flat
b) rpm sensor, if one wheel is going "faster" it's got a smaller (effective) diameter, so the tyre is flat

a) is very hard to measure accurately
b) has to take cornering into account

Lefty,

Since you challenged me to figure this out, I'll have to ask:

  1. if you deflate all tires equally from equally well pressurized initial condition, will your old Buick still tell you low pressure? :roll_eyes:
  2. if you deflate just the front tires but equally, with you get a low pressure warning?
  3. if you park your tire-well-pressured old Buick on a slope (Should be plenty in SF, right?), with its side doors facing the top of the slope, will you get low pressure warning?
  4. if for some reason you're driving your old Buick and it reports to you tire pressure is low, will stopping the car turn off the warning?

I'm thinking about a bubble level (or tilt sensor) running under the car from left to right but if you carry out the above thought experiment and get back to me, I can be more or less certain about my guess.

BTW, I was not googling anything.

liudr:
Lefty,

Since you challenged me to figure this out, I'll have to ask:

  1. if you deflate all tires equally from equally well pressurized initial condition, will your old Buick still tell you low pressure? :roll_eyes:

I don't think so, but I haven't tested that.

  1. if you deflate just the front tires but equally, with you get a low pressure warning?

I think so, but i haven't test that.

  1. if you park your tire-well-pressured old Buick on a slope (Should be plenty in SF, right?), with its side doors facing the top of the slope, will you get low pressure warning?

No, it seems to take some time averaging before it issues a warning after actually driving some distance.

  1. if for some reason you're driving your old Buick and it reports to you tire pressure is low, will stopping the car turn off the warning?

Only if I turn off everything and pull the key out. Warnings can also be reset, but will return if still true, like low oil level, time to change oil, door ajar, etc.

I'm thinking about a bubble level (or tilt sensor) running under the car from left to right but if you carry out the above thought experiment and get back to me, I can be more or less certain about my guess.

No car has to have travels some distance before tire pressure warning is issued.
BTW, I was not googling anything.

Funny, after I first got the Buick I goggled and did fine the method used for my car.

mmcp42:
I'm guessing:
a) level sensor, if one side is low chances are the tyre (sp) is flat

No level sensor involved.

b) rpm sensor, if one wheel is going "faster" it's got a smaller (effective) diameter, so the tyre is flat

You are getting very very warm here. However I will confuse and challenge that it doesn't use a sensor just dedicated to tire pressure warning.

a) is very hard to measure accurately
b) has to take cornering into account

I don't think cornering is a factor. It's not an alarm that comes on instantly, it takes some distance traveled.

well if it's just the rear(driven) wheels you could spot the differential gear turning
OR
if the car has ABS there could be an output from the speed sensors...

mmcp42:
well if it's just the rear(driven) wheels you could spot the differential gear turning
OR
if the car has ABS there could be an output from the speed sensors...

if the car has ABS there could be an output from the speed sensors...

Give the man a cigar. Antilock Braking Systems have a sensor to tell if a wheel is turning or not so as to release brake pressure on a 'lock-up' wheel during a breaking situation. The car just uses this sensor to also determine a rpm for the wheel and does some comparison with the other wheels ABS sensor and reaches a decision if one (or more?) wheels speed differs from the others due to smaller wheel diameter if at lower tire pressure. I'm sure it's not a real sensitive or accurate 'answer' it arrives at, but it is effective enough that after getting such an alarm and stopping and looking at the tires I can't always tell which is the lower one just by eye, I have to measure manual to be sure in most cases.

Lefty