Go to Post There should be no teams yelling "robot". - RoboMom [more]
Home
Go Back   Chief Delphi > Technical > Technical Discussion
CD-Media   CD-Spy  
portal register members calendar search Today's Posts Mark Forums Read FAQ rules

 
Closed Thread
 
Thread Tools Rate Thread Display Modes
  #1   Spotlight this post!  
Unread 22-02-2007, 23:49
AdamHeard's Avatar
AdamHeard AdamHeard is offline
Lead Mentor
FRC #0973 (Greybots)
Team Role: Mentor
 
Join Date: Oct 2004
Rookie Year: 2004
Location: Atascadero
Posts: 5,503
AdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond repute
Send a message via AIM to AdamHeard
Re: A small issue with our Mecanums

Also it sounds like one side is outputing more power than the other.

Are you just setting PWMs or is there some feedback to control the speed?
  #2   Spotlight this post!  
Unread 24-02-2007, 15:39
AGWSPilot AGWSPilot is offline
Registered User
FRC #1415
 
Join Date: Jan 2006
Location: Columbus,GA
Posts: 10
AGWSPilot is on a distinguished road
Re: A small issue with our Mecanums

Quote:
Originally Posted by AdamHeard View Post
Also it sounds like one side is outputing more power than the other.

Are you just setting PWMs or is there some feedback to control the speed?
Currently, we are just using PWM's. I tried in the code to reduce power to several different permutations of wheels, and it made little or no change to the behavior of the system(it still pivoted on the rear wheels), I don't think the problem lies in wheel speed. But thank you for the suggestion.
  #3   Spotlight this post!  
Unread 24-02-2007, 22:49
dtengineering's Avatar
dtengineering dtengineering is offline
Teaching Teachers to Teach Tech
AKA: Jason Brett
no team (British Columbia FRC teams)
Team Role: Mentor
 
Join Date: Jan 2005
Rookie Year: 2004
Location: Vancouver, BC
Posts: 1,829
dtengineering has a reputation beyond reputedtengineering has a reputation beyond reputedtengineering has a reputation beyond reputedtengineering has a reputation beyond reputedtengineering has a reputation beyond reputedtengineering has a reputation beyond reputedtengineering has a reputation beyond reputedtengineering has a reputation beyond reputedtengineering has a reputation beyond reputedtengineering has a reputation beyond reputedtengineering has a reputation beyond repute
Re: A small issue with our Mecanums

If you can get some feedback happening you are going to be a lot happier with your handling, I think. We use shaft encoders to ensure the wheels are all turning at the correct speed to give us the motion we want, while I know of other teams who have reported success using the gyro to stabilize their heading.

If you've got the banebots encoders and divider cards on board, we've developed some code that might be able to help, which we are willing to share. Drop me a PM. If not, it is probably easier to just tack on a gyro... perhaps there is someone willing to share their techniques for gyro stabilization of a mecanum drive.

To see some clips of how we move try http://www.youtube.com/watch?v=gyn9e0cT3-A

Jason

P.S. Some posts surrounding mecanum drives insist that you need a suspension to have a working mecanum drive system. While that may be true on a rough surface, we are quite satisfied with just having a bit of flex in the frame.
  #4   Spotlight this post!  
Unread 18-03-2007, 02:11
Thorcat Thorcat is offline
Registered User
FRC #1540
 
Join Date: Jan 2007
Location: Portland, OR
Posts: 5
Thorcat is an unknown quantity at this point
Re: A small issue with our Mecanums

this may come too late to really help you, but by changing the wheels, you will have to flip your side-to-side controller, otherwise you will go right when you wanto to go left. all other driving functions (forwards, backwards, and spin) like regular tank drive, so it will ramain unaffected.
Closed Thread


Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Small Banebots Motor Issue - Lessened torque and smoke sanddrag Motors 10 12-02-2007 21:41
Issue with downloading code to the 2007 RC thefro526 Programming 3 10-02-2007 17:26
Issue with CMUCam2 Demo application Bio LabView and Data Acquisition 12 21-01-2006 16:08
Our Small Parts Experience, to all TEAMS Anton Abaya General Forum 29 04-02-2002 15:52


All times are GMT -5. The time now is 17:58.

The Chief Delphi Forums are sponsored by Innovation First International, Inc.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Copyright © Chief Delphi