How to design a gearbox?

Does anyone know any book titles or websites that could teach me how to design a multi-motor gearbox (with or without a tranny)? Like a gearbox design for dummies…

http://www.howstuffworks.com should be a good start. I have the physical book, and it has descriptions of both manual and automatic transmissions. It probably covers gearboxes as well.

There are many white papers on here about these sorts of subjects. I think your best bet will be to go with one of the gearboxes already on here. I can speak from experience when I say that designing a tranny from scratch is pretty darn hard. I just tried modifying one and managed to screw it up.

If you’re trying to make one yourself, though, Martin Sprockets has a pretty good guide to sizing gears in their eCatalog. Also, I recommend Mark’s Standard Handbook for Mech E’s, except it’s rather expensive and filled with stuff you don’t need. Machinery’s handbook could also be helpful. I’m unsure there is anything that specific as to tell you exactly how to design a tranny, though.

Finally this white paper seems like it would be the most helpful:
JVN’s FIRST Mechanical Design Calculator

Ohh, the horrors!!! :ahh: Designing a gearbox is a pain. We had the hardest time designing a gearbox that would actually work. Tristan Lall helped quite a bit but we had to make modifications because we decided to use 24" bike wheels. We found that to avoid having two stages of sprockets we had to make very significant modifications. So we did design it and we got it machined but we had lots of trouble with it at the competition. First of all, they turned out to be really heavy with all the 72 tooth gears we had in there. Secondly we had problems with the press-fit bearings falling out. Balancing weight, speed and torque for the very first time was a very big challenge for our two 17-year-old mobility people.

EDIT: We had planned to go up the 6" side of the platform and we had calculated the torque required to do that given the estimated weight distribution of the robot. So we needed more than around 110 Newton metres of torque after taking into account 70% efficiency per gearbox.

This may sound corny, but…

In all seriousness, pull up Amazon.com and search for robotics. You’d be amazed. A teammate and I did this once in school and we were like…drooling at all the cool books we wanted to buy. Sad, I know. =)

There IS a book called “Robot Building for Dummies,” and there’s also an entire series (Robot DNA Series) dedicated to the subject, with one entire book called “Building Robot Drive Trains.” I’m not sure if it has much info on gearboxes specifically, but it does have lots of info about which motors to use and how to mount them. (My copy was recently ordered and is now in the mail. :))

Don’t you love that crazy Canadian Regional?
http://www.firstcanadianregional.org/resources/Workshops/

Howstuffworks.com and the white pages are a good place to start as well. I also suggest getting yourself some legos and playing around with them. You can read as many books as you want, but nothing beats actually putting gears together to get a general idea of how it all works.

Ask other teams. If you’re in Atlanta, just drop by a random team’s pit and they will probably be more than happy to show you what they did and how they did it. If you’re stuck at home like us while everyone else has fun at Nats, look up local teams that may be able to help you.

Books are cool, but I would look into real hands-on experience as well.

I’ve heard these have helped some people in the past… :wink:

Technokat Archived Documents

You might wanna look at Shiftonfly.pdf , Dualmotor.pdf , and 6motor.pdf

Even though they really are not a “teaching tool” for designing gearboxes they might give you some good ideas.

Walk up to Barnes & Nobles and look in the science section. There should be a whole lot of information there. Although, having a mentor helps more.

If you need to know standards and basics of gear train design, go to this website :http://www.sdp-si.com/catalogs.htm . Their books of small standard drive compenents and the Drive Component Design textbook are both really helpful. The textbook has all of your tolerances for press fits and helps you learn the basics of backlash etc. in a drive train. It also has a special section on robotics in the back. All of the books can be viewed online or ordered.
Hope that helped some.
Aaron

Here, I found something useful:
http://www.firstcanadianregional.org/resources/Workshops/Gearboxes.pdf

Another good place to look is www.google.com . There’s a LOT of stuff about gearboxes.

-Bharat

I have both Building Robot Drive Trains and Programming Robot Controllers from the Robot DNA series, and I have to say, they’re both awesome. My copy of the former isn’t right next to me, but it contains information on everything from basic gear design and fundamentals, to DC electric motor designs, to relative / absolute position encoders, to how you can (with a screwdriver and a saw) modify a standard hobby servo to act as a motor (detail about how to remove the hardstop and disconnect the potentiometer, if I recall correctly). Anyway, I highly recommend these books.

Also, as a text reference, I think you should look into a book from Stock Drive Products (SDP-SI) entitled Design and Application of Small Standardized Components. You can order it for free from SDP’s website, and I think it’s a great little resource. Don’t let the name mislead you, it contains information about topics from gear design, to gear train design, to how to heat treat steel, to effeciently and effectively machining materials, to, well, a lot of other great stuff. Did I mention it’s free? I did? Well, it’s still free. They’ll ship it to you with every single one of their catalogs for less than a dime ($0, in fact).

I love these books.

Small parts has a good basic gear guide on their site. It gives you much of the information needed to design a simple gearbox.

You will absolutely want to sign up for the conferences on motors and drive trains at nationals - take notes, ask questions, and get a copy of the presentation material.

How do I sign up? This is the first time I’m going to the nationals…

Team 116’s dual speed/dual motor gearbox whitepaper
Good luck with your gearbox

That is an excellent presentation. In addition to that, this may sound stupid but my best resource for gearboxes (and everything else) has been www.chiefdelphi.com You can get more from this place than you ever imagined, and not just in the whitepapers. Me without ChiefDelphi is like a historian without history. This is a real top quality community that can teach people more than any other single place I know. :slight_smile: