Go to Post If Call Me Maybe is on loop for an entire competition I'm quitting FIRST. - Mike Schreiber [more]
Home
Go Back   Chief Delphi > FIRST > Robot Showcase
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 04-09-2004, 23:06
CD47-Bot CD47-Bot is offline
Registered User
FRC #0047 (Chief Delphi)
 
Join Date: Dec 2002
Location: Pontiac, MI
Posts: 1,616
CD47-Bot has a reputation beyond reputeCD47-Bot has a reputation beyond reputeCD47-Bot has a reputation beyond reputeCD47-Bot has a reputation beyond reputeCD47-Bot has a reputation beyond reputeCD47-Bot has a reputation beyond reputeCD47-Bot has a reputation beyond reputeCD47-Bot has a reputation beyond reputeCD47-Bot has a reputation beyond reputeCD47-Bot has a reputation beyond reputeCD47-Bot has a reputation beyond repute
pic: Iso view

  #2   Spotlight this post!  
Unread 04-09-2004, 23:19
Arefin Bari's Avatar
Arefin Bari Arefin Bari is offline
Registered User
AKA: Ari
FRC #0108 (SigmaC@T)
Team Role: Engineer
 
Join Date: Mar 2003
Rookie Year: 2001
Location: Ft. lauderdale, FL
Posts: 3,248
Arefin Bari has a reputation beyond reputeArefin Bari has a reputation beyond reputeArefin Bari has a reputation beyond reputeArefin Bari has a reputation beyond reputeArefin Bari has a reputation beyond reputeArefin Bari has a reputation beyond reputeArefin Bari has a reputation beyond reputeArefin Bari has a reputation beyond reputeArefin Bari has a reputation beyond reputeArefin Bari has a reputation beyond reputeArefin Bari has a reputation beyond repute
Send a message via ICQ to Arefin Bari Send a message via AIM to Arefin Bari Send a message via MSN to Arefin Bari Send a message via Yahoo to Arefin Bari
Re: pic: Iso view

looks nice... and simple... drivetrains that a lot of teams would go with... i dont see any pneumatics so i am guessing that gearbox cant be shifted into another speed... how fast you are expecting the robot to move and with how much torque... if possible, i would like to see a close view of the drive train... good luck...

Last edited by Arefin Bari : 04-09-2004 at 23:26.
  #3   Spotlight this post!  
Unread 04-09-2004, 23:21
RogerR's Avatar
RogerR RogerR is offline
its spelled *ya'll*, not *y'all*
AKA: Roger Riquelme
FRC #3844 (Wildbots)
Team Role: Teacher
 
Join Date: Feb 2003
Rookie Year: 2001
Location: Somerset, KY
Posts: 913
RogerR has a reputation beyond reputeRogerR has a reputation beyond reputeRogerR has a reputation beyond reputeRogerR has a reputation beyond reputeRogerR has a reputation beyond reputeRogerR has a reputation beyond reputeRogerR has a reputation beyond reputeRogerR has a reputation beyond reputeRogerR has a reputation beyond reputeRogerR has a reputation beyond reputeRogerR has a reputation beyond repute
Send a message via AIM to RogerR Send a message via MSN to RogerR
Re: pic: Iso view

sweet drivetrain. about the weight estimates in CAD, is 60# the estimates for just the machined components, without the manufactured parts (i.e. motors, robot controller, battery) or did you already add those in? also, it looks like you might be using the cap screws in the front and back to move the wheel mounts back and forth, adjusting chain tension. is this the case? finally, how are the motors mounted? i can't tell from looking at the drawings, and its really messing with my head.
__________________
"But to say that the race is a metaphor for life is to miss the point. The race is everything. It obliterates whatever isn't racing. Life is a metaphor for the race." -- Donald Antrim
  #4   Spotlight this post!  
Unread 04-09-2004, 23:34
Rod's Avatar
Rod Rod is offline
Mentor
FRC #0662 (Rocky Mountain Robotics)
Team Role: Mentor
 
Join Date: Dec 2003
Rookie Year: 2003
Location: Colorado Springs, CO
Posts: 98
Rod is a splendid one to beholdRod is a splendid one to beholdRod is a splendid one to beholdRod is a splendid one to beholdRod is a splendid one to beholdRod is a splendid one to beholdRod is a splendid one to behold
Send a message via AIM to Rod
Re: pic: Iso view

Quote:
Originally Posted by Arefin Bari
looks nice... and simple... drivetrains that a lot of teams would go with... i dont see any pneumatics so i am guessing that gearbox cant be shifted into another speed... how fast you are expecting the robot to move and with how much torque... if possible, i would like to see a close view of the drive train... good luck...
Single speed gearbox
Top speed is 8.1 FPS
Gear ratio chip to rear wheel= 8:1
Bosch to rear wheel=32:1
wheel Dia.= 6"
you do the math
__________________
-Rod-
Team 662
Rocky Mountain Robotics
Colorado Springs, CO
  #5   Spotlight this post!  
Unread 04-09-2004, 23:39
Rod's Avatar
Rod Rod is offline
Mentor
FRC #0662 (Rocky Mountain Robotics)
Team Role: Mentor
 
Join Date: Dec 2003
Rookie Year: 2003
Location: Colorado Springs, CO
Posts: 98
Rod is a splendid one to beholdRod is a splendid one to beholdRod is a splendid one to beholdRod is a splendid one to beholdRod is a splendid one to beholdRod is a splendid one to beholdRod is a splendid one to behold
Send a message via AIM to Rod
Re: pic: Iso view

Quote:
Originally Posted by RogerR
sweet drivetrain. about the weight estimates in CAD, is 60# the estimates for just the machined components, without the manufactured parts (i.e. motors, robot controller, battery) or did you already add those in? also, it looks like you might be using the cap screws in the front and back to move the wheel mounts back and forth, adjusting chain tension. is this the case? finally, how are the motors mounted? i can't tell from looking at the drawings, and its really messing with my head.
60# total weight
Cap screws do adj. chains
Motor mounts are slotted and bolted from underneath for a cleaner look
__________________
-Rod-
Team 662
Rocky Mountain Robotics
Colorado Springs, CO
  #6   Spotlight this post!  
Unread 04-09-2004, 23:56
Arefin Bari's Avatar
Arefin Bari Arefin Bari is offline
Registered User
AKA: Ari
FRC #0108 (SigmaC@T)
Team Role: Engineer
 
Join Date: Mar 2003
Rookie Year: 2001
Location: Ft. lauderdale, FL
Posts: 3,248
Arefin Bari has a reputation beyond reputeArefin Bari has a reputation beyond reputeArefin Bari has a reputation beyond reputeArefin Bari has a reputation beyond reputeArefin Bari has a reputation beyond reputeArefin Bari has a reputation beyond reputeArefin Bari has a reputation beyond reputeArefin Bari has a reputation beyond reputeArefin Bari has a reputation beyond reputeArefin Bari has a reputation beyond reputeArefin Bari has a reputation beyond repute
Send a message via ICQ to Arefin Bari Send a message via AIM to Arefin Bari Send a message via MSN to Arefin Bari Send a message via Yahoo to Arefin Bari
Re: pic: Iso view

I should have made another thread about the gearboxes... but okay...

I am just wondering if your motor mounts are strong enough keep the drill motor from spinning out because of torque in the gearbox... i am saying that since i have experienced it... we had something like a mexican hat which held the drill motor in place and then bolted that into the gearbox plate...

The design looks great so far... whoever drew it... put some quality time in it... good luck...
  #7   Spotlight this post!  
Unread 05-09-2004, 00:24
Rod's Avatar
Rod Rod is offline
Mentor
FRC #0662 (Rocky Mountain Robotics)
Team Role: Mentor
 
Join Date: Dec 2003
Rookie Year: 2003
Location: Colorado Springs, CO
Posts: 98
Rod is a splendid one to beholdRod is a splendid one to beholdRod is a splendid one to beholdRod is a splendid one to beholdRod is a splendid one to beholdRod is a splendid one to beholdRod is a splendid one to behold
Send a message via AIM to Rod
Re: pic: Iso view

Quote:
Originally Posted by Arefin Bari
I should have made another thread about the gearboxes... but okay...

I am just wondering if your motor mounts are strong enough keep the drill motor from spinning out because of torque in the gearbox... i am saying that since i have experienced it... we had something like a mexican hat which held the drill motor in place and then bolted that into the gearbox plate...

The design looks great so far... whoever drew it... put some quality time in it... good luck...
Thanks,
We have used this type of mount on the chip motors in the past with no problems. The mount is slotted on one side only and the hole is bored to fit tight on the motor. We'll see if it works, if not redesign
__________________
-Rod-
Team 662
Rocky Mountain Robotics
Colorado Springs, CO
  #8   Spotlight this post!  
Unread 05-09-2004, 00:37
Cory's Avatar
Cory Cory is offline
Registered User
AKA: Cory McBride
FRC #0254 (The Cheesy Poofs)
Team Role: Engineer
 
Join Date: May 2002
Rookie Year: 2001
Location: Redwood City, CA
Posts: 6,821
Cory has a reputation beyond reputeCory has a reputation beyond reputeCory has a reputation beyond reputeCory has a reputation beyond reputeCory has a reputation beyond reputeCory has a reputation beyond reputeCory has a reputation beyond reputeCory has a reputation beyond reputeCory has a reputation beyond reputeCory has a reputation beyond reputeCory has a reputation beyond repute
Send a message via AIM to Cory
Re: pic: Iso view

Looks really nice.

One comment.

It seems to me like the only thing holding the rear plate in alignment is the CIM motor on the left side. You might want to consider adding something in to link the two plates together
__________________
2001-2004: Team 100
2006-Present: Team 254
  #9   Spotlight this post!  
Unread 05-09-2004, 09:05
Greg Perkins's Avatar
Greg Perkins Greg Perkins is offline
7 years, allready!!???!?!?!
AKA: Mongo
no team
Team Role: Alumni
 
Join Date: Feb 2002
Rookie Year: 2000
Location: Nashua, NH
Posts: 1,203
Greg Perkins has a reputation beyond reputeGreg Perkins has a reputation beyond reputeGreg Perkins has a reputation beyond reputeGreg Perkins has a reputation beyond reputeGreg Perkins has a reputation beyond reputeGreg Perkins has a reputation beyond reputeGreg Perkins has a reputation beyond reputeGreg Perkins has a reputation beyond reputeGreg Perkins has a reputation beyond reputeGreg Perkins has a reputation beyond reputeGreg Perkins has a reputation beyond repute
Send a message via AIM to Greg Perkins Send a message via MSN to Greg Perkins Send a message via Yahoo to Greg Perkins
Re: pic: Iso view

It looks awesome guys...

the one thing i see is that the bosch motors are being discontinued this coming year. i dont know what we are gettting but i wouldnt start anything until we find out. just a heads up...


Please dont take this post negatively... I know you must've spent numerous hours on it...and i dont want to sound like a buzzkill
__________________
myResume -2004: PARC Referee; Beantown Staff; Battlecry Referee; Summer Frenzy Head Referee; River Rage Head Referee, 2005: Pittsburgh Regional Referee; PARC Referee


XBOX Live Gamertag = TrixAre4Kidss
  #10   Spotlight this post!  
Unread 05-09-2004, 13:21
Rod's Avatar
Rod Rod is offline
Mentor
FRC #0662 (Rocky Mountain Robotics)
Team Role: Mentor
 
Join Date: Dec 2003
Rookie Year: 2003
Location: Colorado Springs, CO
Posts: 98
Rod is a splendid one to beholdRod is a splendid one to beholdRod is a splendid one to beholdRod is a splendid one to beholdRod is a splendid one to beholdRod is a splendid one to beholdRod is a splendid one to behold
Send a message via AIM to Rod
Re: pic: Iso view

Quote:
Originally Posted by Greg Perkins
It looks awesome guys...

the one thing i see is that the bosch motors are being discontinued this coming year. i dont know what we are gettting but i wouldnt start anything until we find out. just a heads up...


Please dont take this post negatively... I know you must've spent numerous hours on it...and i dont want to sound like a buzzkill
It's just ink on paper now and will stay that way until after kickoff. If they do change the motors it will be a fairly easy edit in CAD. The gears in the gearboxes are Boston Gear change gears. Change gears can be purchased in one tooth increments from 20 to 96. The gears on the motors are Stem Pinion gears and come in 5,6,10 teeth. I chose these gears because they are all 3/8" face. They are all 5/8" bore. 1/8" key way. 20 DP 14.5 PA It makes it easy to mix and match to get the ratio you want. You can see the gears at bostongear.com. Go to Bos Spec 2 , open gearing, spur gears, change gears and stem pinion gears. You can download the CAD files, .STEP files seem to work best in AutoDesk Inventor. You will need to register to access Bos Spec 2, very easy. These gears seem to be a good option for teams like ours who do not want to try and make custom gears.
Gear List
GA20
GA40
NAR5
__________________
-Rod-
Team 662
Rocky Mountain Robotics
Colorado Springs, CO
  #11   Spotlight this post!  
Unread 07-09-2004, 11:10
Tytus Gerrish's Avatar
Tytus Gerrish Tytus Gerrish is offline
IGAB, ADHD, and Dislexic
AKA: Ty
FRC #0179 (SwampThing)
Team Role: Tactician
 
Join Date: Feb 2003
Rookie Year: 2001
Location: West Palm Beach, Florida
Posts: 2,017
Tytus Gerrish has a reputation beyond reputeTytus Gerrish has a reputation beyond reputeTytus Gerrish has a reputation beyond reputeTytus Gerrish has a reputation beyond reputeTytus Gerrish has a reputation beyond reputeTytus Gerrish has a reputation beyond reputeTytus Gerrish has a reputation beyond reputeTytus Gerrish has a reputation beyond reputeTytus Gerrish has a reputation beyond reputeTytus Gerrish has a reputation beyond reputeTytus Gerrish has a reputation beyond repute
Re: pic: Iso view

those gearboxes are HUGE!!! alot more material and complexity than is needed. the batery would be best placed in the front for some balance. it is a verry light tho i warn is a very flimsy chassis using the channel. swampthing is all channel and just a fwe hits tirned it into a crushed tin can. the atonomus had to be guessed everytime because after every match the wheeles would pointed in a diffrent direction.
  #12   Spotlight this post!  
Unread 07-09-2004, 12:00
Billfred's Avatar
Billfred Billfred is offline
...and you can't! teach! that!
FRC #5402 (Iron Kings); no team (AndyMark)
Team Role: Mentor
 
Join Date: Feb 2004
Rookie Year: 2004
Location: The Land of the Kokomese, IN
Posts: 8,556
Billfred has a reputation beyond reputeBillfred has a reputation beyond reputeBillfred has a reputation beyond reputeBillfred has a reputation beyond reputeBillfred has a reputation beyond reputeBillfred has a reputation beyond reputeBillfred has a reputation beyond reputeBillfred has a reputation beyond reputeBillfred has a reputation beyond reputeBillfred has a reputation beyond reputeBillfred has a reputation beyond repute
Re: pic: Iso view

Perhaps it's time for FIRST robots to start using R/C car-type suspensions. You can adjust those things all day long...toe-in, camber, shock positioning, those were the days.

I have to agree--the channel (now that I realize it's channel) would probably be a little flimsy, given the robust trend lately. Perhaps some bracing would be in order? If that channel in the front or the back takes a few too many hits, then you're looking at no support to keep the sides from just ker-flumping inward. (I experienced the same phenomenon when one of my bed's rails at home warped. Ask my brother--we spent half an hour jumping on it to make it look half-decent...and even then, we had to prop a busted computer under the bed so that it'd hold my weight.) That wouldn't be too good in the middle of a match.

As for the weight distribution...I dunno. It would depend on your appendages du jour, but I think you might do well moving the battery back (more into the screen looking at that shot), and moving your RC to the other side. Or move the battery to the other side of the CIM motors and slide your RC inward some. That might help out, especially if the channel does give way. You don't want a good whack doing something to your RC.

Just my random blathering. With a few tweaks, that design should...what's the Chappelle's Show quote...SPIT HOT FI-YAH!
__________________
William "Billfred" Leverette - Gamecock/Jessica Boucher victim/Marketing & Sales Specialist at AndyMark

2004-2006: FRC 1293 (D5 Robotics) - Student, Mentor, Coach
2007-2009: FRC 1618 (Capital Robotics) - Mentor, Coach
2009-2013: FRC 2815 (Los Pollos Locos) - Mentor, Coach - Palmetto '09, Peachtree '11, Palmetto '11, Palmetto '12
2010: FRC 1398 (Keenan Robo-Raiders) - Mentor - Palmetto '10
2014-2016: FRC 4901 (Garnet Squadron) - Co-Founder and Head Bot Coach - Orlando '14, SCRIW '16
2017-: FRC 5402 (Iron Kings) - Mentor

94 events (more than will fit in a ChiefDelphi signature), 14 seasons, over 61,000 miles, and still on a mission from Bob.

Rule #1: Do not die. Rule #2: Be respectful. Rule #3: Be safe. Rule #4: Follow the handbook.
  #13   Spotlight this post!  
Unread 07-09-2004, 15:16
Paul Copioli's Avatar Unsung FIRST Hero Woodie Flowers Award
Paul Copioli Paul Copioli is offline
President, VEX Robotics, Inc.
FRC #3310 (Black Hawk Robotics)
Team Role: Engineer
 
Join Date: Jun 2001
Rookie Year: 2000
Location: Rockwall, TX
Posts: 1,392
Paul Copioli has a reputation beyond reputePaul Copioli has a reputation beyond reputePaul Copioli has a reputation beyond reputePaul Copioli has a reputation beyond reputePaul Copioli has a reputation beyond reputePaul Copioli has a reputation beyond reputePaul Copioli has a reputation beyond reputePaul Copioli has a reputation beyond reputePaul Copioli has a reputation beyond reputePaul Copioli has a reputation beyond reputePaul Copioli has a reputation beyond repute
Re: pic: Iso view

Rod,

I have done the math and something is not adding up.

CIM free speed = 5,500RPM
Gear Ratio to rear wheel = 8:1
Wheel Diameter = 6"

5500 / 8 = 687.5 RPM or 71.995 rad/sec
71.995 rad/sec * 3" (or .25 ft) = 17.99 ft/sec

Assuming some losses, you will be around 14 - 16 ft/sec, not 8!

-Paul
  #14   Spotlight this post!  
Unread 07-09-2004, 16:23
Rod's Avatar
Rod Rod is offline
Mentor
FRC #0662 (Rocky Mountain Robotics)
Team Role: Mentor
 
Join Date: Dec 2003
Rookie Year: 2003
Location: Colorado Springs, CO
Posts: 98
Rod is a splendid one to beholdRod is a splendid one to beholdRod is a splendid one to beholdRod is a splendid one to beholdRod is a splendid one to beholdRod is a splendid one to beholdRod is a splendid one to behold
Send a message via AIM to Rod
Re: pic: Iso view

Quote:
Originally Posted by Paul Copioli
Rod,

I have done the math and something is not adding up.

CIM free speed = 5,500RPM
Gear Ratio to rear wheel = 8:1
Wheel Diameter = 6"

5500 / 8 = 687.5 RPM or 71.995 rad/sec
71.995 rad/sec * 3" (or .25 ft) = 17.99 ft/sec

Assuming some losses, you will be around 14 - 16 ft/sec, not 8!

-Paul
I figured the the top speed at 50% of the CIM free speed
__________________
-Rod-
Team 662
Rocky Mountain Robotics
Colorado Springs, CO
  #15   Spotlight this post!  
Unread 07-09-2004, 16:27
Unsung FIRST Hero
JVN JVN is offline
@JohnVNeun
AKA: John Vielkind-Neun
FRC #0148 (Robowranglers)
Team Role: Engineer
 
Join Date: May 2001
Rookie Year: 2000
Location: Greenville, Tx
Posts: 3,159
JVN has a reputation beyond reputeJVN has a reputation beyond reputeJVN has a reputation beyond reputeJVN has a reputation beyond reputeJVN has a reputation beyond reputeJVN has a reputation beyond reputeJVN has a reputation beyond reputeJVN has a reputation beyond reputeJVN has a reputation beyond reputeJVN has a reputation beyond reputeJVN has a reputation beyond repute
Re: pic: Iso view

Quote:
Originally Posted by Rod
I figured the the top speed at 50% of the CIM free speed
Common mistake.
The motor will run muuuch faster than Max Power.

I usually use a "speed constant" of 85%.
Basically, gear the robot based on .85*free speed or in the Chips case: 4675RPM

Real world testing of my theoretical calculations shows this to be about right.

More accurate drive modelling can be done, but this simple method comes out pretty good. Then again, your milage may vary depending on your drivetrain.

Anyone else wanna confirm 85%?

JV

Edit:
See Andy's post below.
I guess I'm a little fast. Oops.
/Edit
__________________
In the interest of full disclosure: I work for VEX Robotics a subsidiary of Innovation First International (IFI) Crown Supplier & Proud Supporter of FIRST

Last edited by JVN : 07-09-2004 at 17:08.
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
pic: 217 Robot ISO view CD47-Bot Robot Showcase 8 01-03-2004 13:09
pic: 710 2004 side view of drive train CD47-Bot Robot Showcase 6 16-02-2004 19:43
pic: Right Side view CD47-Bot Robot Showcase 2 03-03-2003 15:26
pic: 141's Robot stacking side view CD47-Bot Robot Showcase 7 28-02-2003 12:16
pic: 857 rear view programming CD47-Bot Robot Showcase 1 25-02-2003 22:24


All times are GMT -5. The time now is 03:01.

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