Ultrasonic vs. Infrared

Forum 2005-2010 (read only) Hardware Interfacing
1

Hello!

I am pondering on a project for my garage. It's about installing a visual help to park my car inside.

Now, what kind of sensor should I use?

Infrared Proximity Sensor Long Range

Ultrasonic Range Finder - Maxbotix LV-EZ1

apart the price, which one is more accurate? The distance is not the problem. I only need 1,5m.

Thanks for your advises!!

-andreas

2

I think reliability is more important than accuracy. I would vote for an ultra sonic one.

3

I find the infrared sensor values seem to fluctuate a lot in different light conditions, and depending on the surface in front of them. In the datasheet for my infrared sensor, it had different specs for dark or light targets, and I suspect shiny or dull also makes a difference. For parking the same car, that may not be an issue.

I don't have any experience with the ultrasonic, but I can see how it wouldn't immediately be better by not being subject to those specific limitations. I also had to oversample quite a bit - ten or more samples seemed to get a good approximation of distance with infrared.

However, if you are using two ultrasonic sensors, one for side/side and the other for front/back positions of the car, their bouncing echos may interfere with each other unless the sensors are timed appropriately.

4

Thanks for your hints..

I guess the ultrasonic will be the right choice. I didn't think about lightning issues. Left/Right distance is not an issue.

My project goes like this:

  1. The headlights will trigger the arduino through a photoresistor.
  2. a 8x8 matrix is showing the position of the car using arrows.
  3. If the exact position is found the matrix will show a green O.
    If the position is passed the matrix will show a red X.
  4. The arduino will shut itself if there is no light after 30secs.

What do you think about it? :wink:

-andreas