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Object Sensor

leshea2leshea2 Posts: 83
edited 2005-11-23 20:44 in BASIC Stamp
Can I program the stamp to interface with an Object Sensor and make it so that the Object Sensor only senses objects with a specific mass, like a 12 x 12 x 12 box·?

Thanks !

Comments

  • Tom WalkerTom Walker Posts: 509
    edited 2005-11-23 13:58
    Ouch! (Sorry, that was from the memory of my Physics instructor bemoaning people "not understanding what a unit is a unit of")...

    leshea2,
    Your question raises several others. What kind of "object sensing" are you trying to accomplish? Infra-red, ultrasonic, weight (perhaps Kirlian?<k>)? Comparing mass to volume (12 x 12 x 12) doesn't give a clear picture...

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  • leshea2leshea2 Posts: 83
    edited 2005-11-23 19:07
    I have a IR emitter/receiver pair for close-range optical detection. Now, let's say you wanted to only detect a certain kind of object, instead of just any object in the room. So that being said, can I program the stamp to interface with my IR emitter/receiver and make it so that the IR emitter/receiver only detects objects with a specific mass, value or etc. ?

    Thanks !
  • Tom WalkerTom Walker Posts: 509
    edited 2005-11-23 19:21
    The IR emmitter/detector pair sends out an IR beam and looks for a reflection. This basic sensor is basically a "is something IR reflective there" indicator. With some programming and/or external hardware, it can be worked into a "how far away is something IR reflective" system. For anything more, another sensor or set of sensors will be needed.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Truly Understand the Fundamentals and the Path will be so much easier...

    Post Edited (Tom Walker) : 11/23/2005 7:36:29 PM GMT
  • Steve JoblinSteve Joblin Posts: 784
    edited 2005-11-23 19:24
    Just to make sure, I don't think you are asking the right question... you can't tell how much mass something has just by looking at it. I think you are trying to ask if an IR emitter/receiver can detect an object of a specific shape. Is this correct?

    If the above is correct, then the simple answer is no. an IR Emitter/receiver is simply a device that shines a light and looks for a reflection. It is just that the light is Infra Red, so you can't see it. I is also sent at a specific frequency. The receiver is tuned to look for IR light at that specific frequency.

    You would need a lot of sophisticated imaging equipment and programming to detect a specific shape.
  • Larry~Larry~ Posts: 242
    edited 2005-11-23 19:42
    Maybe
    If you have two IR pairs angled at the correct angle then at a set distance,
    you could pick up a specific size, but the wall would also give you a false reading.
  • leshea2leshea2 Posts: 83
    edited 2005-11-23 20:34
    Thanks, that's vary helpful ! But if a reflective IR object detector works by looking for a reflection, how does a plane object sensor work, or are they the same ?

    Thanks !
  • Don BuczynskiDon Buczynski Posts: 31
    edited 2005-11-23 20:44
    This idea assumes a very controlled operating environment. But if you can limit the scope of "object" to a few known items, I think that something might be possible. The rough shape of the object could be determined by scanning it; perhaps by using a servo mounted IR beam/sensor. The servo is repeatedly positioned by the stamp and the reflected light measured. The object should be isolated enough to minimize reflections from the surroundings. In this way, an outline of the object could be accumulated by the stamp and compared to a table of known objects. The resolution of the scan would be poor but would be useable for simple shaped objects. It might also be possible to refine the scan by using the objects distance (average reflectivity) and the servo position angle.





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