Using raspberry pi to measure angle newbie

[Geejayrail]

Hi

I'm relatively new to the programming game. I'm basically looking for a way to measure an angle on an arm that pivots up and down. I'd like to be able to move the arm to a point I choose, then have a way of it remembering that exact point for example when I press a button, and then it will alarm if I get to that point until I press a reset switch.

I know you can get inclinometers that are compatible. I'd just like to know if it would be possible on the platform?

Kind regards

GJ

[jamesh]

This would be quite an expensive way of doing it.

https://www.leveldevelopments.com/produ ... interface/

There are others.

You could simply have a rotation sensor on the arm pivot perhaps? Or a laser distance sensor? Number of ways of doing it.

EDIT : Or this? https://www.sparkfun.com/products/9836

[Z80 Refugee]

I'd just like to know if it would be possible on the platform?

If you mean without any additional parts (like you can with an Android/iOS phone), the answer is no.

[bensimmo]

if your arm is using a motor and that motor gives feedback, you can use that provide the position. store it in a variable and then just use it for the goto point.

it will be as good as your motor is.

if your arm is using something else, hydraulic etc, see if it has a feedback mechanism you can record.

[bensimmo]

other alternatives rotational potentiometers and adc convertor.
again this will give you the angle/resistance of the point.

we use these with pendulums to datalog the position.

a gyro/accelerometer and read its position, probably quite easy to connect via i2c.

for the alarm, you just check until it goes past the data point you have stored with that push button.

[mark3112]

Linear potentiometer and an ADC?
Type “Linear-Position-Sensor” into ebay.