Angle sensors

Discussion in 'General Electronics Chat' started by Webby, Jul 27, 2014.

  1. Webby

    Thread Starter Active Member

    Jun 15, 2008
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    I'm working on a project and need to know the reason as to why angle sensors use resistance measurement?
     
  2. bertus

    Administrator

    Apr 5, 2008
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    Hello,

    What type of sensors are you talking about?
    There are hall sensors that can detect an angle and there are a kind of gyro related sensors.

    Bertus
     
  3. Webby

    Thread Starter Active Member

    Jun 15, 2008
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    Bertus, basically potentiometer would I be right in thinking the resistance measurement are fast and reliable for checking angle sensors?
     
  4. sirch2

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    Jan 21, 2013
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    A servo potentiometer may be good enough, depending on the accuracy you require
     
  5. jpanhalt

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    Jan 18, 2008
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    For what you seem to be talking about, I suspect a potentiometer is used, because it is cheap, and the output is easily converted to digital or analog representation.

    If you look up goniometer (http://en.wikipedia.org/wiki/Goniometer) you may get more in depth information. For modern tools, an accelerometer may be used to measure the angle (incline) relative to Earth or other reference point.

    John
     
  6. Sensacell

    Well-Known Member

    Jun 19, 2012
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    I assume you are talking about tilt relative to earth's gravity?

    There are electrolytic angle sensors, basically a conductive fluid in a small capsule with specially shaped electrodes- basically a resistive sensor.

    MEMS accelerometers seem to be the best option these days.

    If you are talking about the angle of two mechanical parts in relation to each other- that is another subject with may possibilities.
     
  7. alfacliff

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    Dec 13, 2013
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    the problem with potentiometers for angle measurments are contact wear. inductive angle sensors and optical encoders are much more reliable. accelerometers are usefull on changing angles, but will not give you static angles.
     
  8. mcgyvr

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    Oct 15, 2009
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    Some do.. some don't..
    You are just working with one that does..

    cost
    accuracy
    speed
    ,etc....
     
  9. jpanhalt

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    They most certainly will give a "static" angle, unless you live somewhere with microgravity.

    John
     
  10. studiot

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    Nov 9, 2007
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    Try a forum search. Electronic angle measurement and transducers has been discussed many times here.
     
  11. alfacliff

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    jpanhalt, so the angle output stays the same after cycling the power? an eccelerometer will tell you how much and how fast movement is or was, but when not moving will tell you only that it is not moving. external circuits keep track of movement.
     
  12. jpanhalt

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    Jan 18, 2008
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    You are ignoring the context of the comment, which referred to angles relative to Earth. Thus, you can determine whether something is level, perpendicular, or any angle in between. The result can be constant, as they are continuously exposed to gravity. You can also tell in a constant state the angular difference between two items. Of course, you have to have the accelerometer aligned to the proper axis.

    You may find this application note of interest: http://resenv.media.mit.edu/classarchive/MAS836/Inertialnotes/an-00mx-001.pdf

    John
     
  13. alfacliff

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    Dec 13, 2013
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    there was only one comment made about the relative angle of the earth. the origional poster has not replyed about the use for the angle measurement. where I work, angle measurements are more for machine tool and building measurement use than locating the position in the galaxy.
     
  14. THE_RB

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    Feb 11, 2008
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    You're both right. Accelerometers are fine for measuring angles on a vertical plane. Or a plane that has a significantly large vertical component.

    But the accelerometer can't measure angles on a horizontal plane.
     
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