Go to Post Act humble, avoid hubris, and post widely and thou shalt receivith postive rep. ;) - artdutra04 [more]
Home
Go Back   Chief Delphi > ChiefDelphi.com Website > Extra Discussion
CD-Media   CD-Spy  
portal register members calendar search Today's Posts Mark Forums Read FAQ rules

 
Reply
Thread Tools Rate Thread Display Modes
  #1   Spotlight this post!  
Unread 01-04-2015, 14:22
Landonh12's Avatar
Landonh12 Landonh12 is offline
270 points
AKA: Landon Haugh
FRC #0364 (Team Fusion)
Team Role: College Student
 
Join Date: Jan 2012
Rookie Year: 2012
Location: Gulfport, MS
Posts: 211
Landonh12 has much to be proud ofLandonh12 has much to be proud ofLandonh12 has much to be proud ofLandonh12 has much to be proud ofLandonh12 has much to be proud ofLandonh12 has much to be proud ofLandonh12 has much to be proud ofLandonh12 has much to be proud of
pic: Makeshift Kiwi Vex-FTC-FRC hybrid

Reply With Quote
  #2   Spotlight this post!  
Unread 01-04-2015, 14:28
billbo911's Avatar
billbo911 billbo911 is offline
I prefer you give a perfect effort.
AKA: That's "Mr. Bill"
FRC #2073 (EagleForce)
Team Role: Mentor
 
Join Date: Mar 2005
Rookie Year: 2005
Location: Elk Grove, Ca.
Posts: 2,384
billbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond repute
Re: pic: Makeshift Kiwi Vex-FTC-FRC hybrid

When you say "It didn't work well", what specifically didn't work the way you intended?

BTW, talk about overkill with those speed controllers!!

Here is a quick video I did of a Gyro Stabilized Vex Kiwi robot. So far, it works great. Next step......More speed!!!
__________________
CalGames 2009 Autonomous Champion Award winner
Sacramento 2010 Creativity in Design winner, Sacramento 2010 Quarter finalist
2011 Sacramento Finalist, 2011 Madtown Engineering Inspiration Award.
2012 Sacramento Semi-Finals, 2012 Sacramento Innovation in Control Award, 2012 SVR Judges Award.
2012 CalGames Autonomous Challenge Award winner ($$$).
2014 2X Rockwell Automation: Innovation in Control Award (CVR and SAC). Curie Division Gracious Professionalism Award.
2014 Capital City Classic Winner AND Runner Up. Madtown Throwdown: Runner up.
2015 Innovation in Control Award, Sacramento.
2016 Chezy Champs Finalist, 2016 MTTD Finalist
Reply With Quote
  #3   Spotlight this post!  
Unread 01-04-2015, 14:37
Andrew Schreiber Andrew Schreiber is offline
Joining the 900 Meme Team
FRC #0079
 
Join Date: Jan 2005
Rookie Year: 2000
Location: Misplaced Michigander
Posts: 4,074
Andrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond repute
Re: pic: Makeshift Kiwi Vex-FTC-FRC hybrid

Quote:
Originally Posted by billbo911 View Post
When you say "It didn't work well", what specifically didn't work the way you intended?

BTW, talk about overkill with those speed controllers!!

Here is a quick video I did of a Gyro Stabilized Vex Kiwi robot. So far, it works great. Next step......More speed!!!
Working on similar. One issue I've been running into is the transition between turning and not turning. On the comp bot (H drive) this year we just have the driver toggle between heading lock mode and not. But that's not really a great solution long term. Any suggestions?
__________________




.
Reply With Quote
  #4   Spotlight this post!  
Unread 01-04-2015, 16:04
billbo911's Avatar
billbo911 billbo911 is offline
I prefer you give a perfect effort.
AKA: That's "Mr. Bill"
FRC #2073 (EagleForce)
Team Role: Mentor
 
Join Date: Mar 2005
Rookie Year: 2005
Location: Elk Grove, Ca.
Posts: 2,384
billbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond repute
Re: pic: Makeshift Kiwi Vex-FTC-FRC hybrid

Quote:
Originally Posted by Andrew Schreiber View Post
Working on similar. One issue I've been running into is the transition between turning and not turning. On the comp bot (H drive) this year we just have the driver toggle between heading lock mode and not. But that's not really a great solution long term. Any suggestions?
Absolutely.

How I got the Vex Kiwi to transition between Gyro stabilization (Heading Lock) and open loop control is really simple. I just sampled the "Rotation" input from the joystick, and used a "window" to detect when rotation was being commanded. Any rotation input outside the window caused the gyro input to be ignored and allowed the rotation command to control the rotation of the robot. As soon as the rotation input entered the window again, the current gyro direction value was set to zero and then the gyro direction was used to control the rotation once again.

One key to making this transition smooth is to set the "window" to closely match the range of the "Rotation" command deadband that doesn't quite make a change in the robot's rotation.
IIRC, that range for the Vex was from >122 to <130.
__________________
CalGames 2009 Autonomous Champion Award winner
Sacramento 2010 Creativity in Design winner, Sacramento 2010 Quarter finalist
2011 Sacramento Finalist, 2011 Madtown Engineering Inspiration Award.
2012 Sacramento Semi-Finals, 2012 Sacramento Innovation in Control Award, 2012 SVR Judges Award.
2012 CalGames Autonomous Challenge Award winner ($$$).
2014 2X Rockwell Automation: Innovation in Control Award (CVR and SAC). Curie Division Gracious Professionalism Award.
2014 Capital City Classic Winner AND Runner Up. Madtown Throwdown: Runner up.
2015 Innovation in Control Award, Sacramento.
2016 Chezy Champs Finalist, 2016 MTTD Finalist
Reply With Quote
  #5   Spotlight this post!  
Unread 01-04-2015, 16:25
Landonh12's Avatar
Landonh12 Landonh12 is offline
270 points
AKA: Landon Haugh
FRC #0364 (Team Fusion)
Team Role: College Student
 
Join Date: Jan 2012
Rookie Year: 2012
Location: Gulfport, MS
Posts: 211
Landonh12 has much to be proud ofLandonh12 has much to be proud ofLandonh12 has much to be proud ofLandonh12 has much to be proud ofLandonh12 has much to be proud ofLandonh12 has much to be proud ofLandonh12 has much to be proud ofLandonh12 has much to be proud of
Re: pic: Makeshift Kiwi Vex-FTC-FRC hybrid

Quote:
Originally Posted by billbo911 View Post
When you say "It didn't work well", what specifically didn't work the way you intended?

BTW, talk about overkill with those speed controllers!!

Here is a quick video I did of a Gyro Stabilized Vex Kiwi robot. So far, it works great. Next step......More speed!!!
TI jaguars was all we had for extra motor controllers. We're on low supply. :'(

I actually saw your video with the vex and decided to wire it up with one of our Cortex's.

The problem was that the gyro reading would constantly decrease like there was some kind of drift even though the robot wouldn't be rotating. I don't know why it was doing that, and I only had a class period (1hr 15m) to work on code and getting everything worked out.

I could work on it some more and try to get it to work, but I'm much more fluent in LabVIEW than robotC so I'd rather try getting an FRC sized prototype working.
__________________
Team Fusion 364 - Driver/Programmer 2012-2015; Controls Mentor 2016-Present

Last edited by Landonh12 : 01-04-2015 at 16:28.
Reply With Quote
  #6   Spotlight this post!  
Unread 01-04-2015, 16:46
billbo911's Avatar
billbo911 billbo911 is offline
I prefer you give a perfect effort.
AKA: That's "Mr. Bill"
FRC #2073 (EagleForce)
Team Role: Mentor
 
Join Date: Mar 2005
Rookie Year: 2005
Location: Elk Grove, Ca.
Posts: 2,384
billbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond repute
Re: pic: Makeshift Kiwi Vex-FTC-FRC hybrid

Quote:
Originally Posted by Landonh12 View Post
TI jaguars was all we had for extra motor controllers. We're on low supply. :'(

I actually saw your video with the vex and decided to wire it up with one of our Cortex's.

The problem was that the gyro reading would constantly decrease like there was some kind of drift even though the robot wouldn't be rotating. I don't know why it was doing that, and I only had a class period (1hr 15m) to work on code and getting everything worked out.

I could work on it some more and try to get it to work, but I'm much more fluent in LabVIEW than robotC so I'd rather try getting an FRC sized prototype working.
Clearly a FRC sized prototype is the direction we are heading as well.

As for your gyro drift. The initialization process may not be completing properly before the robot is moved.
I added the red LED to mine to indicate when the initialization process has finished. This bot is coded in "C" using MPLab as the IDE. It's old school, but the principals are the same.
__________________
CalGames 2009 Autonomous Champion Award winner
Sacramento 2010 Creativity in Design winner, Sacramento 2010 Quarter finalist
2011 Sacramento Finalist, 2011 Madtown Engineering Inspiration Award.
2012 Sacramento Semi-Finals, 2012 Sacramento Innovation in Control Award, 2012 SVR Judges Award.
2012 CalGames Autonomous Challenge Award winner ($$$).
2014 2X Rockwell Automation: Innovation in Control Award (CVR and SAC). Curie Division Gracious Professionalism Award.
2014 Capital City Classic Winner AND Runner Up. Madtown Throwdown: Runner up.
2015 Innovation in Control Award, Sacramento.
2016 Chezy Champs Finalist, 2016 MTTD Finalist
Reply With Quote
  #7   Spotlight this post!  
Unread 01-04-2015, 16:49
Alan Anderson's Avatar
Alan Anderson Alan Anderson is offline
Software Architect
FRC #0045 (TechnoKats)
Team Role: Mentor
 
Join Date: Feb 2004
Rookie Year: 2004
Location: Kokomo, Indiana
Posts: 9,113
Alan Anderson has a reputation beyond reputeAlan Anderson has a reputation beyond reputeAlan Anderson has a reputation beyond reputeAlan Anderson has a reputation beyond reputeAlan Anderson has a reputation beyond reputeAlan Anderson has a reputation beyond reputeAlan Anderson has a reputation beyond reputeAlan Anderson has a reputation beyond reputeAlan Anderson has a reputation beyond reputeAlan Anderson has a reputation beyond reputeAlan Anderson has a reputation beyond repute
Re: pic: Makeshift Kiwi Vex-FTC-FRC hybrid

Quote:
Originally Posted by Andrew Schreiber View Post
Working on similar. One issue I've been running into is the transition between turning and not turning. On the comp bot (H drive) this year we just have the driver toggle between heading lock mode and not. But that's not really a great solution long term. Any suggestions?
You want "heading hold" when the driver is not commanding a turn, right? Use whatever joystick input commands the turn to turn off heading hold whenever it's not at neutral, and turn it back on again after the turn is finished. That could be as soon as the joystick is back at neutral, or it could be slightly delayed to account for the robot's inertia. See how the driver likes the handling with various amounts of delay in the reactivation of heading hold mode.
Reply With Quote
  #8   Spotlight this post!  
Unread 01-04-2015, 17:33
Andrew Schreiber Andrew Schreiber is offline
Joining the 900 Meme Team
FRC #0079
 
Join Date: Jan 2005
Rookie Year: 2000
Location: Misplaced Michigander
Posts: 4,074
Andrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond reputeAndrew Schreiber has a reputation beyond repute
Re: pic: Makeshift Kiwi Vex-FTC-FRC hybrid

Quote:
Originally Posted by Alan Anderson View Post
You want "heading hold" when the driver is not commanding a turn, right? Use whatever joystick input commands the turn to turn off heading hold whenever it's not at neutral, and turn it back on again after the turn is finished. That could be as soon as the joystick is back at neutral, or it could be slightly delayed to account for the robot's inertia. See how the driver likes the handling with various amounts of delay in the reactivation of heading hold mode.
So, we attempted this, however as Bill Nye reminds us constantly, "Inertia is a property of matter". The heading lock controller (tuned) would take over as soon as we let go of the stick and it would oscillate because the gyro reading we were going to was behind where we actually were (because robot has inertia when it spins). A delay would resolve this issue. I was curious if there was a better way than that. We thought about sampling the gyro rate and if it was 0 and the commanded rate was 0 we could enable heading lock. As it stands, we drive so little in any given match (HP loader) that it wasn't an issue.

Other approaches I thought about doing but in the end just went with the simple "hold this to lock heading" :

- PID controller on gyro_rate
- Settling time
- Scrapping it and saying "back in my day we didn't have fancy gyros to hold our heading, we did it uphill, both ways, with drill motors"
- Telling the mechanical folks we were never turning and all systems needed to be on a turret
__________________




.
Reply With Quote
  #9   Spotlight this post!  
Unread 02-04-2015, 02:19
billbo911's Avatar
billbo911 billbo911 is offline
I prefer you give a perfect effort.
AKA: That's "Mr. Bill"
FRC #2073 (EagleForce)
Team Role: Mentor
 
Join Date: Mar 2005
Rookie Year: 2005
Location: Elk Grove, Ca.
Posts: 2,384
billbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond repute
Re: pic: Makeshift Kiwi Vex-FTC-FRC hybrid

Quote:
Originally Posted by Andrew Schreiber View Post
... A delay would resolve this issue. I was curious if there was a better way than that. We thought about sampling the gyro rate and if it was 0 and the commanded rate was 0 we could enable heading lock.
....

The problem with using both the command AND rate being at 0 is that you would rarely ever see a gyro rate of 0. Vibration, noise, and drift will all give a reading out of a gyro. All of these tend to average out around 0 if a good calibration is achieved, but it still rarely stops at 0.

As Alan suggested,
Quote:
Use whatever joystick input commands the turn to turn off heading hold whenever it's not at neutral, and turn it back on again after the turn is finished. That could be as soon as the joystick is back at neutral, or it could be slightly delayed to account for the robot's inertia. See how the driver likes the handling with various amounts of delay in the reactivation of heading hold mode.
As for your other suggested options, these two should work quite well.
Quote:
Originally Posted by Andrew Schreiber View Post
- Scrapping it and saying "back in my day we didn't have fancy gyros to hold our heading, we did it uphill, both ways, with drill motors"
- Telling the mechanical folks we were never turning and all systems needed to be on a turret
__________________
CalGames 2009 Autonomous Champion Award winner
Sacramento 2010 Creativity in Design winner, Sacramento 2010 Quarter finalist
2011 Sacramento Finalist, 2011 Madtown Engineering Inspiration Award.
2012 Sacramento Semi-Finals, 2012 Sacramento Innovation in Control Award, 2012 SVR Judges Award.
2012 CalGames Autonomous Challenge Award winner ($$$).
2014 2X Rockwell Automation: Innovation in Control Award (CVR and SAC). Curie Division Gracious Professionalism Award.
2014 Capital City Classic Winner AND Runner Up. Madtown Throwdown: Runner up.
2015 Innovation in Control Award, Sacramento.
2016 Chezy Champs Finalist, 2016 MTTD Finalist
Reply With Quote
  #10   Spotlight this post!  
Unread 02-04-2015, 09:36
paula109 paula109 is offline
Junior Member
no team
 
Join Date: Apr 2015
Location: united state
Posts: 1
paula109 is an unknown quantity at this point
Re: pic: Makeshift Kiwi Vex-FTC-FRC hybrid

good work
Reply With Quote
  #11   Spotlight this post!  
Unread 02-04-2015, 15:19
marshall's Avatar
marshall marshall is offline
My pants are louder than yours.
FRC #0900 (The Zebracorns)
Team Role: Mentor
 
Join Date: Jan 2012
Rookie Year: 2003
Location: North Carolina
Posts: 1,332
marshall has a reputation beyond reputemarshall has a reputation beyond reputemarshall has a reputation beyond reputemarshall has a reputation beyond reputemarshall has a reputation beyond reputemarshall has a reputation beyond reputemarshall has a reputation beyond reputemarshall has a reputation beyond reputemarshall has a reputation beyond reputemarshall has a reputation beyond reputemarshall has a reputation beyond repute
Re: pic: Makeshift Kiwi Vex-FTC-FRC hybrid

Quote:
Originally Posted by Andrew Schreiber View Post
Scrapping it and saying "back in my day we didn't have fancy gyros to hold our heading, we did it uphill, both ways, with drill motors"
This made me laugh pretty hard.
Reply With Quote
Reply


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


All times are GMT -5. The time now is 23:56.

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