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 / 24854
24853  |  24855
Subject: 
Re: Mars rovers use Lego principles?
Newsgroups: 
lugnet.robotics
Date: 
Thu, 5 Jan 2006 04:20:59 GMT
Viewed: 
1510 times
  
As far as I know, it's the standard process for implementing a brake.
All the electric forklift trucks I drove used this method as the main
brake. There was a mechanical emergency brake as well, but the main
brake was to use the motor to generate power.

Rob

dan miller wrote:

Hey, isn't this the same principle the RCX uses to brake motors?  I've never
heard of it being used on larger robots.

"On Spirit and Opportunity, the brakes are designed to keep the rover wheels
from being bumped off course while driving. Dynamic braking is accomplished
via a relay switch that places a short across the motor windings of an
actuator [motor] that is not being used. If that actuator starts to move
unexpectedly, it acts as a generator and the short provides an electrical
load that slows the motor down. The same principle is used to generate
electrical energy for hybrid cars when the brakes are applied."

http://www.planetary.org/news/2004/1209_Mars_Exploration_Rovers_Update_Spirit.html




__________________________________________
Yahoo! DSL – Something to write home about.
Just $16.99/mo. or less.
dsl.yahoo.com






Message has 1 Reply:
  Re: Mars rovers use Lego principles?
 
(...) Aside from the fact that it's a cheap technique (one relay replaces a whole slew of servos, hydrailics, brake pads and disks) - it also doesn't wear out like friction-based brakes do. For Mars rovers, the power recovery must be worth having - (...) (18 years ago, 6-Jan-06, to lugnet.robotics)

Message is in Reply To:
  Mars rovers use Lego principles?
 
Hey, isn't this the same principle the RCX uses to brake motors? I've never heard of it being used on larger robots. "On Spirit and Opportunity, the brakes are designed to keep the rover wheels from being bumped off course while driving. Dynamic (...) (18 years ago, 5-Jan-06, to lugnet.robotics)

4 Messages in This Thread:

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

This Message and its Replies on One Page:
Nested:  All | Brief | Compact | Dots
Linear:  All | Brief | Compact
    

Custom Search

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