27-09-2011 22:18

Re: pic: Sorta WCD

Why are you using the motors apart, with 4 separate gearboxes?

27-09-2011 22:30

MattC9

Re: pic: Sorta WCD

Hmmm, looks like a 624 drive, they are notorious for using dewalts like this. Let me try and find you a few pics it might help. Also how would the chain run work?

27-09-2011 22:39

Jeffy

Re: pic: Sorta WCD

Sorta WCD is sorta cool.


I kid, wanna give us some details please?

27-09-2011 22:49

EricH

Re: pic: Sorta WCD

Function of a DeWalt 3-speed--you can really only fit one motor to a gearbox without adding another gearbox on top of it to join the motors. Why would you need the extra speed? Let's see--extra push, easier transition to high gear, and LUDICROUS SPEED!

It wouldn't hurt to add a chain run to make sure that each side gets both motors powering all the wheels together. I realize that those aren't shown, but it may be worth having if weight (and the field) allow.

28-09-2011 07:11

Hawiian Cadder

Re: pic: Sorta WCD

I am currious as to what ratios are in those dewalts. If i remember correctly it is something like 1-12, 1-16, 1-42. what ratio are you thinking of using for the chain, and what fps does it go?

28-09-2011 08:02

Chris is me

Re: pic: Sorta WCD

I believe with CIMs most people remove a stage to make the transmissions run at 1:3 1:4 1:12.

28-09-2011 09:00

Hawiian Cadder

Re: pic: Sorta WCD

Ahh, that is correct, My experience is with a dewalt and fisher-price pairing.

This also makes a lot of sense because the first stage is held together largely by the plastic casing, while the deeper in stages are much more secure.

28-09-2011 15:53

Frenchie461

Re: pic: Sorta WCD

Just to clarify the ratios on the dewalts with the first stage removed are 12:1, 4:1, and 3:1. These are further reduced by a 22:32 sprocket reduction giving speeds of 5, 13, and 17fps (Thank you JVN for your design calculator). The chain is run past 2 idlers to put the sprocket on the drive motor in the right place to only use 1 chain rather than one for each wheel.

28-09-2011 15:54

Frenchie461

Re: pic: Sorta WCD

I'll try that, but that doesn't work quite as well with performance wheels, so I'll probably change those to plactions in the center 2.

28-09-2011 18:47

PAR_WIG1350

Re: pic: Sorta WCD

Wait, one chain per side or one chain per motor and the 2 closest wheels? While the latter sounds fine, I would not advise the former due to the fact that a single failure would render the robot un-steerable. If two chains are used per side, on the other hand, there is at least some degree of redundancy.

28-09-2011 21:08

Frenchie461

Re: pic: Sorta WCD

1 chain per dewalt, which makes it 2 per side