Go to Post Stacking totes on end; Gives you extra height, alas; Topples with a sneeze. - BethMo [more]
Home
Go Back   Chief Delphi > Technical > Programming
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
  #16   Spotlight this post!  
Unread 01-08-2008, 21:29
Nathan's Avatar
Nathan Nathan is offline
Registered User
FRC #1501 (Team T.H.R.U.S.T.)
Team Role: Alumni
 
Join Date: Sep 2006
Rookie Year: 2007
Location: United States
Posts: 149
Nathan has a spectacular aura aboutNathan has a spectacular aura aboutNathan has a spectacular aura about
Re: Almost balancing Scooter

Yes, a Kalman filter.

http://www.cs.unc.edu/~welch/kalman/

Can't help you out with it though, still haven't figured it out for myself.
__________________
Save money with PriceWombat, a shopping comparison and price tracking tool (that I made!).

Check out my hobby electronics business!

My former robotics team: Huntington County 4-H Robotics
  #17   Spotlight this post!  
Unread 11-08-2008, 16:00
Salik Syed Salik Syed is offline
Registered User
FRC #0701 (RoboVikes)
Team Role: Alumni
 
Join Date: Jan 2003
Rookie Year: 2001
Location: Stanford CA.
Posts: 514
Salik Syed has much to be proud ofSalik Syed has much to be proud ofSalik Syed has much to be proud ofSalik Syed has much to be proud ofSalik Syed has much to be proud ofSalik Syed has much to be proud ofSalik Syed has much to be proud ofSalik Syed has much to be proud ofSalik Syed has much to be proud of
Send a message via AIM to Salik Syed
Re: Almost balancing Scooter

Quote:
Originally Posted by Alan Anderson View Post
Maybe you could do a "delay" in the other direction. Do a simple prediction of what the angle is likely be the next time through the loop, and use that as your feedback value instead of the current angle.

I didn't look closely enough at your code to be certain, but are you sure you have the right sign on your Kd term? It should act to reduce motor speed, but you describe it as causing more current to be drawn.

Also, are you using Victor speed controllers? They have a dead band around the neutral point that makes them a bit unsuited for applications requiring the motors to hold a given position. If you're very careful, you can account for the dead band in software, but you have to make sure everything is appropriately calibrated.
I think the strategy of modelling the response may not work since the time step is so small... and if you were to model it for too many timesteps you get problems with response.

maybe you can introduce a decay coefficient which basically says if the error hasn't changed significantly in the previous N iterations (where N is large enough to account for oscillation type behaviour), and the error is below some constant decay the output by a growing coefficient.
__________________
Team 701
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
Building self balancing scooter- troubles with Integrating Gyro gohan22 Sensors 8 22-01-2009 23:06
Motor specs for self-balancing scooter dunkonu Motors 1 23-02-2008 12:05
Team 862 - Self Balancing Scooter jakep Robot Showcase 15 10-10-2006 21:01
FIRST-made Scooter VEN Chit-Chat 7 25-01-2006 15:36
pic: super scooter CD47-Bot Extra Discussion 12 05-08-2004 18:40


All times are GMT -5. The time now is 01:14.

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