To LUGNET HomepageTo LUGNET News HomepageTo LUGNET Guide Homepage
 Help on Searching
 
Post new message to lugnet.robotics.nxtOpen lugnet.robotics.nxt in your NNTP NewsreaderTo LUGNET News Traffic PageSign In (Members)
 Robotics / NXT / 384
383  |  385
Subject: 
Any experience with measuring rotations?
Newsgroups: 
lugnet.robotics.nxt
Date: 
Sat, 20 Jan 2007 15:18:09 GMT
Viewed: 
10803 times
  
Hi all,

I am working on a "project" where I want to measure some reasonably small
rotations, things on the order of +/- 10 degrees or less.  Just to make it hard,
the force acting on the thing being rotated is small, like, completely
hypothetically, the mass of, say, a Lego soccer ball on the end of a 16-stud
beam.  So, imagine I have, say, a 32-stud length teeter-totter (You know, I
don't think I've ever typed that word before!) and at the fulcrum I have an axle
and I place a ball at the end so that the teeter-totter (there it is again)
tilts.  I want to measure the rotation.

I tried using one of the NXT motors but it takes too much force to move the
axle.  If I increase the force (torque?) through gearing it up (down?) then
there is too much slippage, the gears are too loose, and it doesn't register.

So, I guess I need a force sensor, ie, an NXT scale, but something more than
just the binary on/off of a (not sensitive enough) touch sensor.

Any thoughts?

Thank you,
Rafe



Message has 3 Replies:
  Re: Any experience with measuring rotations?
 
(...) Easy. A light sensor. Point the sensor at a disk that's shaded from white to black. I've used that to detect the distance a robot is from a wall (wall following), using just a black & a white dot (1x1) which are moved in front of the sensor. (...) (17 years ago, 20-Jan-07, to lugnet.robotics.nxt)
  Re: Any experience with measuring rotations?
 
(...) I am not rally an NXT guru, but seems the best way would be to simply measure the distance and calculate the angle. Tommy Armstrong (17 years ago, 20-Jan-07, to lugnet.robotics.nxt)
  Re: Any experience with measuring rotations?
 
(...) I am not really an NXT guru, but seems the best way would be to simply measure the distance and calculate the angle. Tommy Armstrong (17 years ago, 20-Jan-07, to lugnet.robotics.nxt)

13 Messages in This Thread:






Entire Thread on One Page:
Nested:  All | Brief | Compact | Dots
Linear:  All | Brief | Compact
    

Custom Search

©2005 LUGNET. All rights reserved. - hosted by steinbruch.info GbR