pic: Bag of DeWalts

I wonder how many teams would love this on their work bench?

We would love to have those on our workbench, and soon we will :wink:

Doesn’t look like a great way to transport them though, especially with those fragile servos.

My 4500th post! Hooray, I guess. On my way to 5 thousand.

We are so very close to having two of those… why do you have so many? What could you possibly need that many for…

My guess is omni drive

Santa clearly came early this year.

we DO have a bag like that-

tried them and rejected them

too slow and cumbersome for the game (although the power is good)

Good luck


Or maybe he just came late!!!
Very nice looking though.

Too slow? Why?

We’re trying to make our own mock-chassis before build season to test out the Dewalts. I have a lackluster design in the process the Inventor rendering of which I’ll try to post, but it would be great to have some input even here… Why are the Dewalts slow? Or are you referring to the process of putting a transmission like that together?

I’m puzzled too Wayne. We (SPAM) used NBD’s for our drivetrain the last 2 years, never had a problem with them, plenty of speed and torque, definitely the fastest we’ve ever assembled our chassis and drive train since they were so simple to put together. Cumbersome? Find me a more compact 3 speed shifting gearbox, simple to build, simple to mount, simple to changeout.

And robust - SPAM has a bag like that also; 2 years times 4 spares that we never needed and can’t use again since they were built in a previous year (just the gearboxes - the motors are OK to use).


Prior to the 05 season we buillt a protochassis with Dewalts on each of 4 wheels. When tested against our 2003 gearbox in a pushing contest they over-strained and popped out the breakers consistently. Likewise we ran the robot into a wall and found they popped out easily when the robot was forced to stall.

That and the approximate 20% reduction in speed wasn’t worth changing the existing prototypes we have been using. Perhaps the term cumbersome was inaccurate because they are easy to pop in and such but we found they would be buried deep in the chassis and hard to get to under the upper deck.

Yes- it is nice to pop in a prebuilt gearbox, but they werent handling the strain we put on them. We still have them and I can visualize using them for non-drive train applications.

We have something new in the works for 2007- a little stronger and much lighter than the 03 or 06 machines. We didn’t like the idea that some bots could trap us in the corner at times during the season so we designed a simple alternative.

WC :cool:

Dang, I thought I had the 2007 25 drivetrain figured out, but that whole simple thing throws 67 style swerves out the window. Back to the drawing board…

My curiosity level is steadily going up… are you going to have a different set of wheels that lower to change speed? Or wait… are you purposely not saying what you are doing (lol)?

I was about to say that looks like more than 15 pounds of spare parts… but after checking the official definition and then subtracting the motor weights, that looks like you only have 5 pounds of spares there :smiley:

This past season was the first time our team used these, and I have to say, they really get the job done - lightweight, simple to make, and versatile!

Plus, they fit in your carry-on. :smiley: If they let you through. :rolleyes:


You are kinda close with dropping a different set of wheels thing. We have a model that does something like that but it all depends on the game. The drive train next year will be different though.:wink:

I will miss that (in)famous tank of a drivetrain!

Now all you need are some variable diameter wheels and you’ll be all set for the rest of robotics. :smiley:

That’s really simple, just have pneumatic wheels that you can inflate or deflate using the FIRST pneumatic system. :]

I’m confused here. Do you mean that the circuit breakers kept tripping (and presumably resetting) or do you mean that the DeWalt popped out of gear into neutral?

Were these 'bots ('03 and prototype) geared to have the same gear ratio (ie. the same 'bot speed at the same motor RPM)?

-Mr. Van
Coach, RoboDox 599

The circuit breakers tripped. In most of the gearboxes you can usually make a wedge or something to prevent the shifting (at least the manual means).

The 03 bot was geared to be a little faster but we hoped that we could use the Dewalts as a replacement with little loss of speed. Instead of making a sophisticated gearbox and adding the Dewalts to it we hoped to bypass the need for two nested gearboxes. After all, why would we want to add them if we were building a gearbox anyway? (no need to reply) The Dewalts simply didnt function to our requirements.

For many teams these might be the answer to their needs. It depends on how hard you press them.


Steve + Corey = a new wave in design to figure out how to keep them from breaking our robots. But like someone said…variable wheel size isn’t a bad idea :slight_smile: