Go to Post 3 weeks vacation here...every single day devoted to volunteering for FIRST. Am I crazy? Yes...I am most definately crazy...but crazy has never been this much fun. - Andy Grady [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
  #16   Spotlight this post!  
Unread 04-01-2005, 16:35
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: 1,393
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
Hypoid

Here is a picture of a hypoid gear. It is used on an automotive painting robot that my company manufactures.
Attached Thumbnails
Click image for larger version

Name:	hypoid1.JPG
Views:	111
Size:	95.8 KB
ID:	2718  

Last edited by Paul Copioli : 04-01-2005 at 16:39.
  #17   Spotlight this post!  
Unread 04-01-2005, 16:36
Matt Adams's Avatar
Matt Adams Matt Adams is offline
b(o_o)d
FRC #1525 (Warbots)
Team Role: Engineer
 
Join Date: Dec 2003
Rookie Year: 2000
Location: Arlington Hts. IL
Posts: 375
Matt Adams has a reputation beyond reputeMatt Adams has a reputation beyond reputeMatt Adams has a reputation beyond reputeMatt Adams has a reputation beyond reputeMatt Adams has a reputation beyond reputeMatt Adams has a reputation beyond reputeMatt Adams has a reputation beyond reputeMatt Adams has a reputation beyond reputeMatt Adams has a reputation beyond reputeMatt Adams has a reputation beyond reputeMatt Adams has a reputation beyond repute
Send a message via AIM to Matt Adams
Post Re: Worm Gear Gearbox

Quote:
Originally Posted by Adam Y.
Actually efficiency might not be an issue if you properly design the gearbox. A little bit of engineering and you should be able to get the efficiency fairly high. Of course a little research shows that the efficiency can reach 60%.
I'm going to have to strongly disagree about efficiency not being an issue.

Even with your research, which I won't refute, 40% losses in a single stage of a gear set is still quite large compared to the 10%-15% losses over an entire drive train with spur gears and chain.

It should be noted that Adam's article did cite a 97% efficiency for a multiple stage gear train using worm gears, which I found to be quite impressive. (Costs? Yikes! )

Worm gears have their place, but I would strongly discourage their use on a drive train if you're just looking to reduce your gear ratio. I'd definitely like to see justification addresing the losses, which we can all admit are several times larger than spur gears.

(See Paul's link for an appropriate application.)

Matt
__________________
Matt Adams - Engineer at Danaher Motion
Team 1525 - Warbots - Deerfield High School

Last edited by Matt Adams : 04-01-2005 at 16:46.
  #18   Spotlight this post!  
Unread 04-01-2005, 16:38
Peter Matteson's Avatar
Peter Matteson Peter Matteson is offline
Ambitious but rubbish!
FRC #0177 (Bobcat Robotics)
Team Role: Engineer
 
Join Date: Sep 2003
Rookie Year: 2003
Location: South Windsor, CT
Posts: 1,653
Peter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond repute
Re: Worm Gear Gearbox

The worms we used last year were 35:1 on the back of another transmission. I don't recall the ratio for the Bosch tranny we used however. We wanted an extremely high torque setup for our application though.

Pete
  #19   Spotlight this post!  
Unread 04-01-2005, 18:02
Jim Schaddelee's Avatar
Jim Schaddelee Jim Schaddelee is offline
Team 107 Holland Christian / Metal
None #0107 (Team Robotics)
Team Role: Mechanical
 
Join Date: Nov 2004
Rookie Year: 1997
Location: Holland ,MI
Posts: 154
Jim Schaddelee has much to be proud ofJim Schaddelee has much to be proud ofJim Schaddelee has much to be proud ofJim Schaddelee has much to be proud ofJim Schaddelee has much to be proud ofJim Schaddelee has much to be proud ofJim Schaddelee has much to be proud ofJim Schaddelee has much to be proud of
Re: Worm Gear Gearbox

Here is a design for positioning worm transmission from team 107 , the nice thing about our design is that there is 50 to 1 reduction on the worm which should make it not back drive. yet you can quickly change speeds and motor combination. It also can have either a pot or encoder mounted simply.



Thanks Jim schaddelee team 107
  #20   Spotlight this post!  
Unread 04-01-2005, 18:35
Doug G's Avatar
Doug G Doug G is offline
Coach / Teacher
FRC #0701 (Robovikes)
Team Role: Coach
 
Join Date: Dec 2002
Rookie Year: 2001
Location: Fairfield, CA
Posts: 880
Doug G has a reputation beyond reputeDoug G has a reputation beyond reputeDoug G has a reputation beyond reputeDoug G has a reputation beyond reputeDoug G has a reputation beyond reputeDoug G has a reputation beyond reputeDoug G has a reputation beyond reputeDoug G has a reputation beyond reputeDoug G has a reputation beyond reputeDoug G has a reputation beyond reputeDoug G has a reputation beyond repute
Re: Worm Gear Gearbox

We used two FP's last year to build a winch for climbing the bar. Be very careful about efficiency loss - we had ~ 30% loss. But it did lock up nicely and keep us hanging

Here's an mpeg of it running
Attached Thumbnails
Click image for larger version

Name:	DSC02180.jpg
Views:	82
Size:	83.4 KB
ID:	2723  Click image for larger version

Name:	DSC02181.jpg
Views:	79
Size:	87.9 KB
ID:	2724  
__________________
Work Hard, Have Fun, Make a Difference!

  #21   Spotlight this post!  
Unread 04-01-2005, 19:38
Jim Schaddelee's Avatar
Jim Schaddelee Jim Schaddelee is offline
Team 107 Holland Christian / Metal
None #0107 (Team Robotics)
Team Role: Mechanical
 
Join Date: Nov 2004
Rookie Year: 1997
Location: Holland ,MI
Posts: 154
Jim Schaddelee has much to be proud ofJim Schaddelee has much to be proud ofJim Schaddelee has much to be proud ofJim Schaddelee has much to be proud ofJim Schaddelee has much to be proud ofJim Schaddelee has much to be proud ofJim Schaddelee has much to be proud ofJim Schaddelee has much to be proud of
Re: Worm Gear Gearbox

Doug

That looks great ,what was your reduction and did you lubricate the worm with anything?

Jim Schaddelee team 107
  #22   Spotlight this post!  
Unread 05-01-2005, 11:46
Adam Y.'s Avatar
Adam Y. Adam Y. is offline
Adam Y.
no team (?????)
 
Join Date: Mar 2002
Location: Long Island
Posts: 1,979
Adam Y. is a splendid one to beholdAdam Y. is a splendid one to beholdAdam Y. is a splendid one to beholdAdam Y. is a splendid one to beholdAdam Y. is a splendid one to beholdAdam Y. is a splendid one to beholdAdam Y. is a splendid one to behold
Send a message via AIM to Adam Y.
Re: Worm Gear Gearbox

Quote:
Worm gears have their place, but I would strongly discourage their use on a drive train if you're just looking to reduce your gear ratio. I'd definitely like to see justification addresing the losses, which we can all admit are several times larger than spur gears.
To be honest I have seen a design that could work but it is really weird. It's the triple crown of complexity because it combines a worm gear, a cone drive, and a differential to increase the horsepower of a motor. The only disadvantage is speed is lost.
__________________
If either a public officer or any one else saw a person attempting to cross a bridge which had been ascertained to be unsafe, and there were no time to warn him of his danger, they might seize him and turn him back without any real infringement of his liberty; for liberty consists in doing what one desires, and he does not desire to fall into the river. -Mill

Last edited by Adam Y. : 05-01-2005 at 11:49.
  #23   Spotlight this post!  
Unread 05-01-2005, 12:00
Pat Roche Pat Roche is offline
Mechanical Engineer
FRC #0134 (Team Discovery)
 
Join Date: Aug 2003
Rookie Year: 2000
Location: Pembroke, NH
Posts: 211
Pat Roche is a splendid one to beholdPat Roche is a splendid one to beholdPat Roche is a splendid one to beholdPat Roche is a splendid one to beholdPat Roche is a splendid one to beholdPat Roche is a splendid one to beholdPat Roche is a splendid one to behold
Send a message via AIM to Pat Roche
Re: Worm Gear Gearbox

Quote:
Originally Posted by Dr.Bot
I did this as an experiment using the plastic gearboxes, shafts and axels suplied by first and purchased gears - there is a post somewhere of someone else who did this. The Chippawa moters fed into this I think it was a 30 fold reduction - so the speed was about 4fps. So comparable to a Fischer Price, but much more powerful, Unfortunately my entire robot platform was thrown out in a fit of spring cleaning - the gears cost about 300 bucks for two sets.

I had some pictures, put heck if I can find them.

SO worm gears will work, and you can make the transmissions with just a good drill press if you are carefull and precise.

I got the gears from "Boston Gear"

worm GH1076RH gear G1071RH

Boston gear also produces stock worm drive gear boxes, they're really efficient for worm drives and are quite heavy duty. we used one in our drive train last year and it worked beautiful. Picture Here. I beleive these were a 20 to 1 reduction and these had no backdrive.

-Pat
__________________
Team Discovery #134 Alumni 1999-2004
Division by Zero #229 Alumni 2004-2009
Team Discovery again?
2010 and Beyond


Where have the last 11 years have gone?
  #24   Spotlight this post!  
Unread 05-01-2005, 12:10
dddriveman's Avatar
dddriveman dddriveman is offline
Former Driver 1038, 979
AKA: Driveman
FRC #1038 (Thunderhawks)
Team Role: Alumni
 
Join Date: Feb 2003
Rookie Year: 2001
Location: Dayton
Posts: 142
dddriveman has a spectacular aura aboutdddriveman has a spectacular aura about
Send a message via AIM to dddriveman
Re: Worm Gear Gearbox

Quote:
Originally Posted by Pat Roche
Boston gear also produces stock worm drive gear boxes, they're really efficient for worm drives and are quite heavy duty. we used one in our drive train last year and it worked beautiful. Picture Here. I beleive these were a 20 to 1 reduction and these had no backdrive.

-Pat
I did not think that you could buy gearboxes. I was under the impresion that you could only manufacturing them. Plus what is the fun in using premanufactured gearboxes, you dont even get the headaches or any of the flesh wounds that come with designing and building a custom gearbox. That is what makes it fun or at least when it is all over.
__________________
"I'm sorry, after all he is just a wookie!"
  #25   Spotlight this post!  
Unread 05-01-2005, 12:18
Jaine Perotti Jaine Perotti is offline
...misses her old team.
AKA: BurningQuestion
FRC #0716 (The Who'sCTEKS)
Team Role: Alumni
 
Join Date: May 2004
Rookie Year: 2003
Location: Melbourne, FL
Posts: 979
Jaine Perotti has a reputation beyond reputeJaine Perotti has a reputation beyond reputeJaine Perotti has a reputation beyond reputeJaine Perotti has a reputation beyond reputeJaine Perotti has a reputation beyond reputeJaine Perotti has a reputation beyond reputeJaine Perotti has a reputation beyond reputeJaine Perotti has a reputation beyond reputeJaine Perotti has a reputation beyond reputeJaine Perotti has a reputation beyond reputeJaine Perotti has a reputation beyond repute
Send a message via AIM to Jaine Perotti Send a message via MSN to Jaine Perotti Send a message via Yahoo to Jaine Perotti
Re: Worm Gear Gearbox

Quote:
Originally Posted by dddriveman
I did not think that you could buy gearboxes. I was under the impresion that you could only manufacturing them.
Yes, you can buy gearboxes. Here is a well known example.

Quote:
Plus what is the fun in using premanufactured gearboxes, you dont even get the headaches or any of the flesh wounds that come with designing and building a custom gearbox. That is what makes it fun or at least when it is all over.
This is really up to the needs and opinions of each individual team.

If they feel that a purchased gearbox will meet their needs better than one that they designed and built themselves, then they should by all means go for it.

If they feel that they want the experience of designing and building their own, and have a unique design that they feel would meet their needs, then they should go ahead and do it.

The decision to buy or build is a matter of what each team feels is best for them.

For more thoughts on the matter... this thread.

-- Jaine
__________________
Florida Institute of Technology
Ocean Engineering, '12
  #26   Spotlight this post!  
Unread 05-01-2005, 12:20
Kevin Sevcik's Avatar
Kevin Sevcik Kevin Sevcik is offline
(Insert witty comment here)
FRC #0057 (The Leopards)
Team Role: Mentor
 
Join Date: Jun 2001
Rookie Year: 1998
Location: Houston, Texas
Posts: 3,760
Kevin Sevcik has a reputation beyond reputeKevin Sevcik has a reputation beyond reputeKevin Sevcik has a reputation beyond reputeKevin Sevcik has a reputation beyond reputeKevin Sevcik has a reputation beyond reputeKevin Sevcik has a reputation beyond reputeKevin Sevcik has a reputation beyond reputeKevin Sevcik has a reputation beyond reputeKevin Sevcik has a reputation beyond reputeKevin Sevcik has a reputation beyond reputeKevin Sevcik has a reputation beyond repute
Send a message via AIM to Kevin Sevcik Send a message via Yahoo to Kevin Sevcik
Re: Worm Gear Gearbox

Quote:
Originally Posted by dddriveman
I did not think that you could buy gearboxes. I was under the impresion that you could only manufacturing them. Plus what is the fun in using premanufactured gearboxes, you dont even get the headaches or any of the flesh wounds that come with designing and building a custom gearbox. That is what makes it fun or at least when it is all over.
For the most part, you can use whatever you can buy off the shelf, mechanically. So gearboxes are perfectly legal as long as they aren't custom made. Viz. AndyMark

Most people talk about building gearboxes for custom functions that an off the shelf one wouldn't fit for, or more commonly for a shifting transmisson that is difficult and expensive to obtain off the shelf. Or was, at any rate. See: Nothing But Dewalts
__________________
The difficult we do today; the impossible we do tomorrow. Miracles by appointment only.

Lone Star Regional Troubleshooter
  #27   Spotlight this post!  
Unread 05-01-2005, 14:39
Peter Matteson's Avatar
Peter Matteson Peter Matteson is offline
Ambitious but rubbish!
FRC #0177 (Bobcat Robotics)
Team Role: Engineer
 
Join Date: Sep 2003
Rookie Year: 2003
Location: South Windsor, CT
Posts: 1,653
Peter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond reputePeter Matteson has a reputation beyond repute
Re: Worm Gear Gearbox

In the case of off the shelf worm gear transmission, aka speed reducers, a COTS part is much heavier than a custom one. My experience with these is that they designed for heavy machinery and not the applications that we have.

One of the best off the shelf transmission choices 177 has made in the last few years was to get the trailer jack the chip was designed for and use that to power our shoulder in 2003. There are lots of good Commercial Off The Shelf parts if you know where to look.
  #28   Spotlight this post!  
Unread 05-01-2005, 14:50
OneAngryDaisy OneAngryDaisy is offline
not on CD enough...
no team
Team Role: Alumni
 
Join Date: Oct 2002
Rookie Year: 2000
Location: Rochester, NY
Posts: 785
OneAngryDaisy is a glorious beacon of lightOneAngryDaisy is a glorious beacon of lightOneAngryDaisy is a glorious beacon of lightOneAngryDaisy is a glorious beacon of lightOneAngryDaisy is a glorious beacon of lightOneAngryDaisy is a glorious beacon of light
Re: Worm Gear Gearbox

341 used a worm gear gearbox last year- we had a CIM geared down to match the drill motor on both sides, she wasn't as fast as we would have liked her to be (efficiency loss), but the entire year we never got pushed once- many times we met teams with much more powerful transmissions and they couldn't budge us, our frame got really beat up from that

but seeing as our main strategy was to hang quickly from the ground, winch up to the platform, and move back and forth on the platform, it was nice to know nobody could push us.

I personally am a fan of the multi-speed gearboxes over this worm gear gearbox, but if there was ever a game where you want to be a unmovable rock, like if you have to guard something, this gearbox is your man.
  #29   Spotlight this post!  
Unread 06-01-2005, 21:54
dddriveman's Avatar
dddriveman dddriveman is offline
Former Driver 1038, 979
AKA: Driveman
FRC #1038 (Thunderhawks)
Team Role: Alumni
 
Join Date: Feb 2003
Rookie Year: 2001
Location: Dayton
Posts: 142
dddriveman has a spectacular aura aboutdddriveman has a spectacular aura about
Send a message via AIM to dddriveman
Re: Worm Gear Gearbox

Quote:
Originally Posted by OneAngryDaisy
341 used a worm gear gearbox last year- we had a CIM geared down to match the drill motor on both sides, she wasn't as fast as we would have liked her to be (efficiency loss), but the entire year we never got pushed once- many times we met teams with much more powerful transmissions and they couldn't budge us, our frame got really beat up from that

but seeing as our main strategy was to hang quickly from the ground, winch up to the platform, and move back and forth on the platform, it was nice to know nobody could push us.

I personally am a fan of the multi-speed gearboxes over this worm gear gearbox, but if there was ever a game where you want to be a unmovable rock, like if you have to guard something, this gearbox is your man.
Maybe this years game will give us a reason to produce a gearbox with wormgears. I would get no greater satisfaction out of life than watching another bot try to push us around.
__________________
"I'm sorry, after all he is just a wookie!"
  #30   Spotlight this post!  
Unread 06-01-2005, 22:06
Max Lobovsky's Avatar
Max Lobovsky Max Lobovsky is offline
Fold em oval!
FRC #1257 (Parallel Universe)
Team Role: College Student
 
Join Date: Jan 2004
Rookie Year: 2004
Location: Scotch Plains, NJ
Posts: 1,026
Max Lobovsky has a brilliant futureMax Lobovsky has a brilliant futureMax Lobovsky has a brilliant futureMax Lobovsky has a brilliant futureMax Lobovsky has a brilliant futureMax Lobovsky has a brilliant futureMax Lobovsky has a brilliant futureMax Lobovsky has a brilliant futureMax Lobovsky has a brilliant futureMax Lobovsky has a brilliant futureMax Lobovsky has a brilliant future
Send a message via AIM to Max Lobovsky
Re: Worm Gear Gearbox

Does anybody have any links to information for calculating worm gear strength?
__________________
Learn, edit, inspire: The FIRSTwiki.
Team 1257


2005 NYC Regional - 2nd seed, Xerox Creativity Award, Autodesk Visualization Award
2005 Chesapeake Regional - Engineering Inspiration Award
2004 Chesapeake Regional - Rookie Inspiration award
2004 NJ Regional - Team Spirit Award
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
gears Michael Leicht Inventor 12 16-09-2004 10:52
Reverse Gear FizMan Technical Discussion 12 26-04-2004 01:29
Van Door Worm Gear Jim Giacchi Motors 4 16-12-2003 09:35
what's your most important drive train advice? Ken Leung Technical Discussion 42 07-01-2003 09:58
"Motors and Drive train edition" of Fresh From the Forum Ken Leung CD Forum Support 6 29-01-2002 12:32


All times are GMT -5. The time now is 16:55.

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