Subject:
|
Re: super cheap tilt sensor?
|
Newsgroups:
|
lugnet.robotics
|
Date:
|
Thu, 23 May 2002 12:27:01 GMT
|
Original-From:
|
PeterBalch <[PeterBalch@compuserve.]antispam[com]>
|
Viewed:
|
773 times
|
| |
|
|
A polaroid filter attached to a pendulum works very well indeed.
You need a lightbulb, a piece of polaroid attached to a pendulum, a fixed
piece of polaroid then a photoresistor. I've made tilt-sensors like that
and they're reliable but, of course, still have problems with inertia and
momentum.
Decades ago, I used to attach sensors to each joint of a crab's leg to
investigate how they swam. Everything had to be tiny and immune to
seawater. I used a "grain of wheat" lightbulb on one side of the joint and
a photo-transistor on the other. As the distance between them varied, you
got a measure of the angle of the joint. You could do the same with a
pendulum.
I recall once glueing a 1mm dia glass tube onto a Selenium solar-cell so as
to measure the level of a (dark) liquid in the tube. In your case, the tube
could be half of a U-tube to measure tilt. It didn't work very well but a
Cadmium-sulphide photoresistor or a photodiode would probably work far
better (photoresistors have a more linear response).
Peter
|
|
1 Message in This Thread:
- Entire Thread on One Page:
- Nested:
All | Brief | Compact | Dots
Linear:
All | Brief | Compact
|
|
|
|
Active threads in Robotics
|
|
|
|
|
|
