To LUGNET HomepageTo LUGNET News HomepageTo LUGNET Guide Homepage
 Help on Searching
 
Post new message to lugnet.roboticsOpen lugnet.robotics in your NNTP NewsreaderTo LUGNET News Traffic PageSign In (Members)
 Robotics / 21770
21769  |  21771
Subject: 
RE: an idea, can someone tell me if this is possible/been donebefore/etc?
Newsgroups: 
lugnet.robotics
Date: 
Tue, 2 Dec 2003 21:20:51 GMT
Original-From: 
Rob Limbaugh <RLIMBAUGH@GREENFIELDGROUP.stopspamCOM>
Viewed: 
2313 times
  
<SNIP>

> With regard to obstacle detection for legs, I was playing
> around with various ways of measuring the increased torque a
> motor puts out in a stalled condition. I was thinking of a
> spring (ie rubber band) loaded co-axial ratchet/cam that
> would hit a switch to tell the robot the leg was blocked and
> it needed to be put down now. That way it would work
> irrespective of the direction of translation (things can
> block the leg both ways).

Look up Tri-Star Wheel.  Instead of driving wheels, drive gears that
move legs (or pneumatic pumps).

Remember that a Tri-Star Wheel uses a differential.  When the input
shaft is turned, it spins the body of the differential which turns the
individual wheels in the Tri-Star configuration.  When a wheel hits an
obstacle, it stops the differential body from rotating so the output
shaft begins to rotate which spins the entire Tri-Star wheel.

If the differential body was connected to the drive train that swings
the leg forward/backward and the output shaft was connected to the
lift/lower drive train, then when the leg stalls (forward/backward) the
system would engage the lift/lower drive train.

Hopefully that made sense...

- Rob



Message has 1 Reply:
  Re: an idea, can someone tell me if this is possible/been donebefore/etc?
 
(...) Doug Carlson has working examples: (URL) (...) I understand it. (...) Kevin (23 years ago, 2-Dec-03, to lugnet.robotics)

2 Messages in This Thread:

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

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