Reducing the weight of the KitBot

[Andy120369693]

Does anyone know of any ideas on how to lose weight on this year's drive train?? What does everyone think of the weight, with the weight of the gear box and the chassie it weighs almost 30 lbs already. Is there anyone who knows if there is a way to get the gear box to run w/ only one motor? The gear box alone, w/ 2 motors, weighs almost 9 lbs.

[Anchi]

ther are instructions included to only use one motor

[DarkJedi613]

Originally Posted by Andy120369693

Does anyone know of any ideas on how to lose weight on this year's drive train?? What does everyone think of the weight, with the weight of the gear box and the chassie it weighs almost 30 lbs already. Is there anyone who knows if there is a way to get the gear box to run w/ only one motor? The gear box alone, w/ 2 motors, weighs almost 9 lbs.

I'm assuming you mean the drive train that came with the kit. Simple, drill some holes (in everything possible) until you A) Lose enough weight or B) Think by drilling more you'll lose structural integrity.

The best way may be to create your own drive train.

[Ben Piecuch]

I'd like to comment on the KOP transmissions, and put a new perspective on them. We built our own transmissions last year, for a single speed, single motor (CIM) drivetrain. We had to do some design work, purchase gears/shafts/material, and then spent about 1 week machining all the pieces. In the end, we had an efficient, smooth, very effective gearbox, which was flawless throughout a years worth of competition. But, it heavily taxed our team resources, and delayed our autonomous testing for over a week.

This year, we've compared the KOP gearboxes with the ones we built last year. These offer a similar gear ratio, the ability to mount one or two motors, and can be assembled in one hours time with absolutely no machining. Also, these gearboxes weight about 1 pound more (each) than our custom-made, heavily machined gearboxes. To me, it's a no-brainer. These KOP gearboxes are wonderful, and with a minimum of machining time can be kept to the same weight as our previous gearboxes. Not to mention, we'll have a driving chassis by the end of the weekend. Way to go Paul on a great addition!

Bengineer
Team 228

[Cory]

Originally Posted by Anchi

ther are instructions included to only use one motor

Not true, they were designed to use either one or two motors. The video shown at kickoff specifically showed two motors being installed.

As for weight reduction, you can drill holes or mill pockets into the gears, as well as drilling holes into the sprockets.

[ShadowKnight]

I think what he meant to say was exactly what you said, that you don't have to use all 4 cims to power your drive train, that you have the option to choose a 2 motor per transmission set-up or only one motor per transmission set-up.

[Matt Adams]

Originally Posted by Ben Piecuch

To me, it's a no-brainer. These KOP gearboxes are wonderful, and with a minimum of machining time can be kept to the same weight as our previous gearboxes.

I must whole heartedly agree.

If you're going to be using a single speed drive train, you need to strongly justify NOT using these. Every team only has so many person-hours and engineering talent at their disposal.

FIRST isn't all about making everything from scratch. In the real world, very little usually is.

On a side note.. something to think about. I've seen a few people suggest lightening the gear cases via drilling holes or something of that nature. I haven't given it a ton of thought, but initially, the case itself is very light. Having a mostly sealed gearbox seems like a good idea to me.

I've never heard someone say, "I'm really glad I had this gear box wide open. The dirt and metal chips really improved our performance."

I've definitely heard the opposite, "Why didn't we just cover this gear box with a sheet of .010" polycarbonate to keep all the junk out?

You might want to consider drilling a couple of 3/8" holes above the gears you use to spray a little lubricant, but outside of that... you really can't beat it.

My $.02,

MJA

[Rosiebotboss]

Originally Posted by Matt Adams

I must whole heartedly agree.

If you're going to be using a single speed drive train, you need to strongly justify NOT using these. Every team only has so many person-hours and engineering talent at their disposal.

FIRST isn't all about making everything from scratch. In the real world, very little usually is.

On a side note.. something to think about. I've seen a few people suggest lightening the gear cases via drilling holes or something of that nature. I haven't given it a ton of thought, but initially, the case itself is very light. Having a mostly sealed gearbox seems like a good idea to me.

I've never heard someone say, "I'm really glad I had this gear box wide open. The dirt and metal chips really improved our performance."

I've definitely heard the opposite, "Why didn't we just cover this gear box with a sheet of .010" polycarbonate to keep all the junk out?

You might want to consider drilling a couple of 3/8" holes above the gears you use to spray a little lubricant, but outside of that... you really can't beat it.

My $.02,

MJA

We are leaning in the direction of using the provided gear boxes as well. The thought we had was to cut a window for inpection and lube, replacing the cut away with polycarbonate keeping out dirt and tetras.

[GMorin]

We were able to cut the weight of EACH gear by up to 50% or so.
The gears have very large diameter hubs. I made an arbor with a key slot to hold the gears on a lathe and turned the diameter of the hubs.
On the thicker hub-less gears, trepanning the faces of the gears works well.
In addition to the lathe work, all gears had holes drilled into them. If you have a Bridgeport mill, this job is a lot easier.

[Rich Wong]

Originally Posted by DarkJedi613

I'm assuming you mean the drive train that came with the kit. Simple, drill some holes (in everything possible) until you A) Lose enough weight or B) Think by drilling more you'll lose structural integrity.

The best way may be to create your own drive train.

I would be very careful about attempting this.
I'm not a M.E. but you maybe ordering a new KOP tranny very soon.
Try reducing weight in other areas.