💬 Optical Inclinometer

  • My maybe stupid question.
    Why use this three state optical device instead of something from those:


    Maybe if I do not use microcomputer, but three relays for something drive directly........

  • Hardware Contributor

    @stevem How does this refer to MySensors technology?

  • Admin


    This is a open source hardware project posted on openhardware.io. It does not necessarily have to be MySensors specific.

  • Hardware Contributor

    @hek Thanks for the clarification. All this time I have been thought that this resource is open hardware area for projects related to the MySensors technology. 😄

  • The reason for this design is because existing MEMS devices (gyro/accelerometer/compass) don't define "YAW" the same as is done in the aviation community. This was originally designed for this "yaw detection" purpose and in fact works in conjunction with an Arduino microcontroller and a gyro/accelerometer board. No relays are needed in this case but could be used if desired. The project was listed on this site simply because it could potentially have uses outside of the original application. Its principal purpose is to provide a "skid" indication in an aircraft, but will work on any vehicle experiencing this condition during a turn.

  • Hero Member

    Does it give the angle, or does it just indicate if the angle is greater or less than 5 degrees? If the latter, I'm wondering how this is different than a ball switch or similar tilt sensor.


  • @stevem
    I know how it works, because I spend some time at glider cabin, when I was young.
    It is very simple and useful device for visual checking.
    But for electronic processing I can imagine two accelerometers connected at some angle at "V" form.
    If values from both are the same - "ball is at centre", do not matter at which G you drive your curves.
    And if two values are different, you obtain proportional error from center position, what can be useful for PID regulator for example.
    Maybe I forgot about something, but I think, it can work this way.

  • The detectors are positioned at a specific distance from the center. If the ball interrupts the light at any of the three detectors, it drops the logic level to a LOW. This means, for example, if it moves to the right detector and switches the logic level, the system remains in this state until the ball returns to the center position. This operational sequence tells the microprocessor whether the right or left detector has been triggered and subsequently whether or not it has returned to the center. The only case when it functions as a simple tilt indicator is when there are no turning forces involved. During a turn in a vehicle (car or aircraft), the centrifugal/centripetal forces come into play as well. This is how a skidding condition is detected: The microprocessor first observes which way the aircraft is banked and then compares that with the observed direction of ball movement. If the bank angle is to the left, for example, but the ball has moved to the right, that's a skid. If they're in the same direction however, it's a "slip", which, in the intended application, is much less important than a "skid".