pic: 2004 drive 930

[CD47-Bot]

loading photo ...

[shawny963]

This is Team 930's drive train for 2004. What do you all think?

[sanddrag]

I'm curious as to what's going on with the Chia stuck in the drill tranny. Could you provide some more info?

[greencactus3]

wait! i thought the CIM motors and the drill motors ran at different speeds, 20000rpm free for the drills and 5500rpm free for the CIMs.
i'm guessing thats a drill transmission on the CIM. even with the drill in low and the CIM in high, there would be a 5500/20(20:1planetary reduction in highgear)=275rpm out put. and 300rpm in low gear for the drill......
wait........ 25rpm (theoretical) difference.... and theres a clutch so you cant kill the motors.
heeeey, thats a really good idea. little late for giving us an idea for the drive train now! reeeeaally helpful...(no) well, not that we have our drive train done yet but.....
but, very interesting. i like it!

[fox46]

Are you guys sure you can use four drill transmissions? Isn't that like using four drill motors?

[Kevin Sevcik]

Presumably, drill motor transmissions fall under the "Off-the-shelf" section of the Parts flowchart. They aren't the actual motor, so they're not illegal that way, and they should theoretically be available to all teams, so it's not a problem as long as you account for the costs.

[rlowerr_1]

I guess some explanation on this one is needed.

We took apart the drill transmissions to remove the anti reverse pins as usual this year. As I opened the transmission and had all the guts fall out an idea popped into my head. We knew that this year we wanted to have a dual motor drive but when we looked into it over the off season we were quickly turned away from all the special gears and custom parts that would have to be made.

It was so simple I thought… lets just run the cim motor through the drill transmission! With all the planetary gears spilled out on the table we found the calculations for finding the reduction of planetary gears and started counting teeth. And low and behold that by only using the last two stages of gears inside the transmission we calculated that the cim would be running at around 349 RPM compared to our measured value of 335 RPM off the drill in low gear. An almost perfect match that can be calibrated by either monitoring current of both drive motors or by capping the max speed of the motors to match each other.

More info on the actual construction will be posted later.