pic: Crude Crab
 

Re: pic: Crude Crab
 

Just saying, but the motor on the module that is drawn for the wheel is improbable. its pointing down and then you have chain going down from it

Re: pic: Crude Crab
 

It really is just an idea of a motor/gearbox/chain combo. I could've drawn more axels, but I was going to use this to explain my ideas in a thread a few days ago, forgetting that it takes a while for pictures to get through.

Re: pic: Crude Crab
 

Just...as another FYI, the things that run the chain are called sprockets...not gears. :D.

Other than that...looks good.

Re: pic: Crude Crab
 

Again, to restate because you guys missed it the first time, this is a rough drawing. I understand all of the components that would go into my little sketch. I was trying to convey a very basic idea. If you have anymore feedback upon the details, reread my posts before you comment.

Re: pic: Crude Crab
 

Sorry about the whole sprocket thing, but I meant it as a joke.

I looked back at it again and the only problem I potentially forsee in this particular design is that it might not be usable in competition. If your intake system needs an opening on one side of the chassis, then having chain that wraps all the around will not work, but then again, that really depends on the year's game.

You might wanna try a system where each side turns independently.

Re: pic: Crude Crab
 

You could get around this by having 3 chains instead of the one linking the 4 modules, leaving 1 side open

All 3 swerves we've made (1625) have had this steering chain setup, 1 big loop.

(prototype 07 and 08)

Re: pic: Crude Crab
 

BTW, you don't have to use Solidworks or Inventor to get ideas out. You might want to look into 3ds Max (comes in the kit), Paint (pre-installed on windows), or even google sketch up. Our team use to do that when we had ideas. It helps to see ideas more organized. Plus Paint is pretty simple to use.

Great Sketch,

-RC

Re: pic: Crude Crab
 

Actually, you can have all of the pods hooked up AND have an intake. On the side in which you desire to have the intake your shafts will need to be extended to clear the intake and then the chain can run across the divide. Correct me if I am wrong, I believe that Trinity team 40 had their chain drive over their intake.

However I do agree that it might be a good idea to rig the two pod sides together to help save weight and complexity.

Re: pic: Crude Crab
 

You don't have to have every module chained to two other modules. For the explanation, I'm going to use FL, FR, BL, and BR for front left, front right, back left and back right, so just a heads up.

If you have the opening in the front and the motor in the middle of the back, you have the motor directly chained to BL and BR. Then BL is chained to FL and BR is chained to FR. That's 4 segments of chain. FL and FR are not chained together, which leaves the entire front part of the robot between the wheels open, and you still get single-motor-steering crab drive.

Re: pic: Crude Crab
 

If you go with a single chain run all the way around you will not have enough chain wrap on the steering motor to transfer loads properly. You could get around this with a few idler sprockets but I would just move the steering motor more inboard to gain more wrap.

Re: pic: Crude Crab
 

I just looked at the robot and they chains do indeed go over the intake. However, there is a piece of 1"X1" aluminum tubing between the chain and the ball path.

Conversely, 190's robot's chain path comes around the collector at the front of the robot (imagine a big "[" around the collector). We have had no problems with the steering motors or chain path all year. Be advised your mileage may vary.

Re: pic: Crude Crab
 

Aw, that's not a crude crab. This is a crude crab:

Re: pic: Crude Crab
 

Take a look again. The motor is horizontal. It sits partly inside the housing.

Re: pic: Crude Crab
 

Keep the picture and the comments and put them in your binder, maybe we can work on building one in the pre-season. Thank's for the input guys.