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Need Help - Building own parking sensors

  1. Sep 28, 2010 #1
    Hi I am relatively new to electrical engineering, I want to make my own parking sensors for a motorcycle, dont ask me why, I would just like to play about with the idea. Could anyone suggest what sort of sensors I would need and frequencies etc?, I am looking to have one seperate transmitter and one receiver.

    Many Thanks

  2. jcsd
  3. Sep 28, 2010 #2
    Probably the easiest ones to use would be ultrasonic transducers. Most of the cheap ones use 40 kHz. You need to determine the maximum range and the minimum range you want to measure. The minimum range sets the limit on how long your pulse can be and the maximum range determines your maximum pulse repetition rate.

    And welcome to PF.
  4. Sep 28, 2010 #3
    Thanks for your quick response skeptic, I am looking for a range of around 0.2 - 1 metres, anything you can recommend?


  5. Sep 28, 2010 #4
    It's so many years since I've worked with ultrasonics I really don't have any recommendations.

    Here is a little on this type of transducer. Since your range will be short and you need wide angel coverage instead of the pencil beam these transducers produce, I was wondering if the beam couldn't be spread out more by funneling it down to a smaller orifice in front of the transducer.

  6. Sep 28, 2010 #5


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    Staff: Mentor

    Welcome to the PF. What's a parking sensor for a motorcycle? What do you want it to do?
  7. Sep 28, 2010 #6
    My ex-wife was obsessed with better ways of parking.

    She tried a tennis ball hanging via a string from the ceiling. This was my favorite. It was cheap.

    She also tried a device with a base and a flexing "stick" and sign. Essentially the stick would bend when you bumped it and you'd see the top flex. Still pretty good.

    Then, she purchased a machine that would detect the car and a red light would come on. This was just getting silly, but she really likes it. And, hey I like to see people happy :)

    Me, I look at the reflections of my head lamps. They narrow as I approach the wall.

    With a bike, I would think that you could see most anything. Could tape do the job?
  8. Sep 28, 2010 #7


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    Gold Member

    How about a couple of low (1") bumps on the floor? The beauty of this is that they don't have to guide you by sight, making you responsible for complying - they guide you physically - the car will stop between the two bumps. You'd have to touch the gas to get it to go over the 2nd bump.

    This will help your wife park, not you.
  9. Oct 12, 2010 #8
    Thanks for all your info, what Im trying to produce is a sensor system I can magnetically attach to the rear of a motorcycle to detect obstacles behind me while wheeling it around. It only needs to have a buzzer to alert when too close, however what Im having trouble deciding is whether to use ultrasonics or electromagnetic. I also have the small issue of the sensor box/ central controller unit. Like Ive said the range is about 0.2M to 1M

    I am quite lost with this and would appreciate anymore help


  10. Oct 12, 2010 #9
    Check a junkyard and see if you can get some of the sensors out of a car that has this function (object detection/collision avoidance). I know 2002+ Ford Explorers had this.

    There are other simple, low-cost sensors you could use such as :

    However, this is not sealed, so the elements would kill it pretty quickly.
  11. Oct 12, 2010 #10


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    Gold Member

    IMHO, electromagentic is going to have several problems: the distance is probably too great, and your bike is made of metal.

    Ultrasonic is likely a better candidate.
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