Help Motor Help

I’m trying to design a protype crab drive for next year. I am wondering which motors is most fit for the wheels and can you get 4 of them on your robot? Or how do you gear a crab drive with only 1 or 2 drive motors?
Please Help

Most of the crab drives I have seen used the CIM motors on 2 wheels and the Drill motors on the other 2 wheels- although you would have to gear the motors up or down to a equal ratio. I’d reccomend you check out a robot with crab drive, email a team that has built one, and check out the whitepapers on gearing, etc- [Edit- You can only use the motors that are provided in that year’s kit. If FIRST put 4 drill motors in next year’s kit (highly unlikely) then you could use a 4 drill motor crab drive. Most likely, you’ll have to figure out gear ratios and mess with the CIM and drill)

a crab drive is no simple mechanism, my team (5 years experience) has never built one… last year we witnessed a totally awesome, experienced team struggle through 3 competitions with no functional drive because they mistakenly made their crab drive external- so make SURE your drive is internal (i.e. wildstang, etc) so the crab modules are protected from impact. One hit, and you’re dead- good luck with this undertaking, there’s nothing better than the feeling when you finish

[edit] check out this whitepaper, ironically 226 used the bosch and FP [/edit]

I’ve been looking at some crab drives lately, so this was a great post to run across. My problem is that I can’t open the white page…is there something I have to load to open it or what. Help would be greatly appreciated.

I get a File Conversion box in MS Works that asks to select the encoding that makes the document readable…probably my problem…do I have to download a certain encoding?

Ask WildStang, they had an awesome robot last year with the crab drive train,

Thank You!
We use modifications of crab drive from year to year as appropriate. In the past (2003) two wheels had drills and two had FPs. The gearing ws different to provide similar wheel RPM and about 8 Ft/Sec speeds. Come look at our robot in the pits at nationals and bring a camera. Anyone there will be able to give an explanation and let you hold one of the spares for investigation. The module bolts on to the robot base and is removable as a single piece. It contains the motor, wheel, all gearing and at least one will have rotation sensors built on. The unit fits into a virtual cylinder 6" diameter and about 12" high and is driven from above by a Globe and chain. The module is indepenent of the steering so it can be changed out in less than a minute.

I got the crab drive inspiration from seeing video of Wildstangs robot from last year. It great watching it slide all over the field.

Would someone Please tell me how I can open up the Whitpaper!!!

The file is zipped so you need an unzip utility. I like WINZIP which you can get freeware from a number of sites. Try this site, it has some great software for free or next to…

Thanks for the help…but I’m still having problems. I can unzip the file, and get the DWG file, but when I open it up in MS Word, I get a box asking me for an encoding that will make my document readable. If I open it with any other encoding I get something like.

AC1015 Ü sJ V ÉL ¾ L W, jx 5 :y a { z0• N(™‚ å^Aà_:M ÿw ÿÿÿÿ “ “ 6k% )5 ±k% A %mÔ6((WÊ?D +sI P S I ( ´ b èD ÿÿÿ ÿÿÿ ÿÿÿ ÿÿÿ ÿÿÿ ÿÿÿ ÿÿÿ ÿÿÿ ÿÿÿ ÿÿÿ 3 f ™ Ì ÿ 3 33 f3 ™3 Ì3 ÿ3 f 3f ff ™f Ìf ÿf ™ 3™ f™ ™™ Ì™ ÿ™ Ì 3Ì fÌ ™Ì ÌÌ ÿÌ ÿ 3ÿ fÿ ™ÿ Ìÿ ÿÿ 3 3 3 f 3 ™ 3 Ì 3 ÿ 3 33 333 f33 ™33 Ì33 ÿ33 f3 3f3 ff3 ™f3 Ìf3 ÿf3 ™3 3™3 f™3 ™™3 Ì™3 ÿ™3 Ì3 3Ì3 fÌ3 ™Ì3 ÌÌ3 ÿÌ3 ÿ3 3ÿ3 fÿ3 ™ÿ3 Ìÿ3 ÿÿ3 f 3 f f f ™ f Ì f ÿ f 3f 33f f3f ™3f Ì3f ÿ3f ff 3ff fff ™ff Ìff ÿff ™

–which isn’t too usefull :smiley:

If I’m not badly mistaken, .DWG is AutoCAD format, which Word would not be able to view, you would need AutoCAD to check it out.

thats correct…auto cad or any mainstream cad software should be able to interpet the file

You can also get free cad file viewer plugins for IE.

That might be my problem…thanks a lot…I’ll have to wait until school to look at it now…darn.