I have received the following query. There is no reason for not publishing for everyone to see and comment on. However please try to make comments helpful, not a slanging match as this is a serious project.

were doing a project on inclinometer, we know that tilt sensors are out in the market.. however we're thinking to do it more on the analog based inclinometer using the potentiometer and a weight attached to it. our problem is we cant come up with a good circuit design for us to start with this one. we're hoping you can impart your knowledge on us.

I don't think that a weight applied to a pot shaft is a good way to go. The shaft friction is unpredictable. The mechanical design to cause rotation to the same point for a given angle and to prevent the weight pulling the shaft right round is difficult.

If you want to build your own inclinometer I would suggest investigating either toothed / perforated wheels on a common shaft, which you can register with a light beam. This is a transmissive system. Or you could go for a reflective system reflecting from coded patterns painted on a wheel. For an analog system if you painted a spiral of increasing brush-width on a wheel and measured the width where it intersected a fixed beam of light this would be proportional to rotation.

 

Hello,

Here is a nice article on encoders.
http://mechatronics.mech.northwestern.edu/design_ref/sensors/encoders.html

The link comes from the EDUCYPEDIA page on encoders and resolvers.
http://www.educypedia.be/electronics/sensorsencoders.htm

Greetings,
Bertus

 

Use a curved traugh with two strips side by side on the bottom , one metalic, other resistive[ paper strip covered with pencil lead?] Place a round ball [ or dollop of mercury ] in traugh. Apply voltage to ends of strip, metalic contact becomes the slider . Bias one input of an OP AMP to = level , othrr to ct. tap. Adj gain to convenient level; output porportional to +-slope. Might try a nicrome wire & a copper one of same guage.

 

I have received the following query. There is no reason for not publishing for everyone to see and comment on. However please try to make comments helpful, not a slanging match as this is a serious project.

You could also use a variable reluctance scheme....a couple of magnets with a moveable plate. Probably a bit more mechanical than the optical encoder, but truly analog.

eric


I don't think that a weight applied to a pot shaft is a good way to go. The shaft friction is unpredictable. The mechanical design to cause rotation to the same point for a given angle and to prevent the weight pulling the shaft right round is difficult.

If you want to build your own inclinometer I would suggest investigating either toothed / perforated wheels on a common shaft, which you can register with a light beam. This is a transmissive system. Or you could go for a reflective system reflecting from coded patterns painted on a wheel. For an analog system if you painted a spiral of increasing brush-width on a wheel and measured the width where it intersected a fixed beam of light this would be proportional to rotation.

You could also use a variable reluctance scheme....a couple of magnets with a moveable plate. Probably a bit more mechanical than the optical encoder, but truly analog.

eric

 

If you can find Hall effect sensors with an unmodified output so their response is in proportion to the intensity of a magnetic field, then a small magnet hung on a string equidistant from 3 or 4 sensors should give good results. Take some calibrating, though.

 

Use a curved traugh with two strips side by side on the bottom , one metalic, other resistive[ paper strip covered with pencil lead?] Place a round ball [ or dollop of mercury ] in traugh. Apply voltage to ends of strip, metalic contact becomes the slider . Bias one input of an OP AMP to = level , othrr to ct. tap. Adj gain to convenient level; output porportional to +-slope. Might try a nicrome wire & a copper one of same guage.

I didn't know mercury came in "dollop" form.

 

I didn't know mercury came in "dollop" form.

One dollop = mercury from 3, 96 in. flourescent lamps, or what we could get from a broken thermometer.