Universal/Standard Drive Base

Originally Posted by Dennis Jenks

I don't know about that..........some would say that 254 has done ok since standardizing their drivetrain in 2004.

It was my interpretation that this would be a larger effort than a single team, and thus that it was similar to the "open source" bases that have been tried in the past.

Simply standardizing a style of drive base inside of a team is relatively simple and effective, and if that's the direction this is going, good luck and I hope the results for your team are as potent as others.

[Wayne TenBrink]

Instead of a single "universal/standard drive base" for all occasions, why not develop your own "drive base system" - along the lines of the Ansy Mark "C-Base" chassis in the KoP but better? The kit frame can be configured for long or wide chassis, 4WD or 6WD, different wheel size & type, etc. Regardless of the final configuration, it uses standardized frame rails & mounting hardware, motor mounts, axles, chain tensioning, etc.

We have been developing our own drive base "system" over the past few years. It doesn't look anything like the kit chassis, but it includes components that accomplish the same basic functions - and more. It has "standardized" structural elements, structural element fasteners, axles, gearbox mounts, chain tensioners & idlers, etc. It can be adapted for wide or long, various wheel arrangements (size & quantity), different ground clearance, "U" or rectangle (as viewed from above), etc. In the fall, we design and prototype improvemed components. After kickoff, we figure out what configuration we need for the game, lay out the detailed plan, and design new components if needed. It still requires some thought and takes time to build. However, it is faster than starting from scratch and frees up brain cells to concentrate on the manipulator. The parts are all based on proven concepts, and we have a lot more flexibility than we would with the kit chassis. We are usually cutting chips by the end of the first week and driving by the third week - long before the manipulator is done. So far, none of the components have been identical from year to year, but the improvements are becoming more "evolutionary" than they are "revolutionary".

There is nothing particularly special or ingenious about our "system". It is the product of our teams experience and efforts, and it works for us. Over time, I think most teams develop their own approach to the various bits of drive base hardware. I encourage you to approach your drive base design as a collection of "universal/standard components" that can be mixed, matched, and modified as needed, rather than a "universal/standard" assembly.

[kevinhorn]

You have nothing to lose and lots to gain from this endeavor. The fact that more than one person has said that it cannot be done is good reason to try. You may find that they are right but you will still be better prepared for next season after an in-depth study of different drive systems.
Considering different materials is a great idea. As a robot inspector I savor every non Al frame!

[NickE]

Originally Posted by Dennis Jenks

I don't know about that..........some would say that 254 has done ok since standardizing their drivetrain in 2004.

Although we have used extremely similar drivebases each of the past seven years, we don't go into the build season restricting ourselves to just one style. Although the style of manufacture will probably stay the same (because that is what we can build easily), the drivetrain design could change drastically.

For example, in 2009, we spent weeks deliberating on whether to build a long or wide robot. Eventually, we decided on long not because it was what we had done before, but because we believed it allowed us to optimize our superstructure. In retrospect, that may have not been the right decision, but that is a debate for another day.

[Chris is me]

Originally Posted by Daniel_LaFleur

Emphisis mine.

Also, be aware that the rules may change for next year ... but as of right now, no final designs can be created prior to kickoff.

True, but the claim was that any design work done in the off season has to be posted.

Originally Posted by kevinhorn

Considering different materials is a great idea. As a robot inspector I savor every non Al frame!

You've gotta inspect in Wisconsin then.

[artdutra04]

"Plans are nothing. Planning is everything." -Dwight Eisenhower

[,4lex S.]

For this to be successful, ensure you are smart about it. Develop what you think to be a solid all around drivetrain, but make it highly adaptable to whatever changes might be made.

So basically, what should happen assuming you have done the research, is a simple, robust 6-8WD system that will serve you well with a few simple modifications 95% of the time. Don't write this option off as too easy, I once made that mistake. Optimizing a 6-8WD is a very tough and entertaining challenge that I am sure could keep my engineering department at work pretty busy for a couple weeks.

My team agreed to do a simple skid steer in 2009, and we did. It worked well, but because we decided to do a wide robot base, it was a lot better than the original design would have been for Lunacy. If you are really enthused about an adaptable design, you could create an iAssembly in inventor that changes drastically to reflect different parameters you choose on creation (I have yet to try this, so I don't know how hard it is).

[kevinhorn]

Originally Posted by Chris is me

True, but the claim was that any design work done in the off season has to be posted.

Daniel is pretty sharp! I don't think that he is contradicting the rules. Especially since he posted that great explanation of my claim that to use off season design work you must post it.
He may be saying that to select a design concept prior to knowing the configuration that best suits the game is unwise.

Two other things;
Design and concept are often used as if they are interchangeable.
I emphasize to my team that a concept is an idea maybe with some drawings.
A design is a set of documents that include: Key Performance Parameters, Drawings, a parts list, a budget and a timeline to finished product. Optimally this would also include calculations but this gets skipped more often than not.
You may call it what you like but being clear in your own mind when you have a design or merely a concept can be useful.

I am a big fan of 6 wheel skid steer But!... That has been done.
After dabbling in a copy of the AM 8" mecanums this year, I am eager to see more advanced drive platforms. Steering and suspension would be a great advance for many teams. Portland Jesuit came up with a really simple design for steering using a swivel on a Toughbox and steering with a globe.
Both front and back wheel sets could steer. That gave the team good steering and a limited ability to skew. This sort of simple but functional design is exciting because only a few teams have tried it and there is lots of room for innovation.

Originally Posted by Chris is me

You've gotta inspect in Wisconsin then.

I would love to visit Wisconsin but Salt Lake is looking really cool and is closer.
Want to meet in the middle?