pic: FRC971 Spartan Robotics Presents: Renegade

[BJC]

Hmmm, 4:57 and 6:04 were pretty unexpected, but I guess they are unveiling week 5 anyways. Looks like a narrow robot with a pretty slick over the bumper collector and a high shooter (probably turreted) Sweet..

Edit: narrow because the fender sticks out 38ish inches.

Originally Posted by BJC

Hmmm, 4:57 and 6:04 were pretty unexpected, but I guess they are unveiling week 5 anyways. Looks like a wide robot with a pretty slick over the bumper collector and a high shooter (probably turreted) Sweet..

How do you get that from the video? I've watched those segments about 20 times myself, and though I see bits of it, I can't tell too much from it.

[Tom Bottiglieri]

Originally Posted by BJC

Hmmm, 4:57 and 6:04 were pretty unexpected, but I guess they are unveiling week 5 anyways. Looks like a narrow robot with a pretty slick over the bumper collector and a high shooter (probably turreted) Sweet..

Edit: narrow because the fender sticks out 38ish inches.

Yes, Yes, No.

[Nuttyman54]

Originally Posted by Akash Rastogi

That is such a clean and beautiful design. You folks always inspire me with your sheetmetal work, and this is no different.

A couple questions:
1. That gearbox orientation looks really nice, would you mind posting a picture of the gearbox/internals of your drive?

Thanks for the compliments Akash, the team is really proud of this one. This is the best picture of the transmission I could dig up is here.

There may be some better pictures that surface later, but the whole thing is buttoned up pretty tight, so it's a little hard to see what all is going on inside.

I don't know the final weight offhand (one of the students can probably weigh in on this), but this is a nice picture of our driver, Scott, holding up the frame with one hand.

[Dan_Karol]

That is one good looking, and sounding, robot. I really like the speed and control you appear to have in the driving videos.

good luck at your competition.

[tzjin]

Elegant indeed! Everything is super streamlined, though I'm a tad confused about why you feel a need to cool your CIM's that much. Your new wheel design looks really great as well; zipties make for a pretty nifty way to replace tread.

I look forward to seeing you guys at SVR! It's going to be a fun year competition

[kevincrispie]

Originally Posted by tzjin

Elegant indeed! Everything is super streamlined, though I'm a tad confused about why you feel a need to cool your CIM's that much. Your new wheel design looks really great as well; zipties make for a pretty nifty way to replace tread.

I look forward to seeing you guys at SVR! It's going to be a fun year competition

Same!

We cooled the CIMs in a similar manner last year. It helps us practice longer and drive longer, really. The motors get quite hot. The way our driver drives, you would want fans on the CIMs.

here's a link to last year's discussion
http://www.chiefdelphi.com/forums/sh...8&postcount=18

The extended runtime is useful when we have a high match turnaround (practice rounds, elims, etc)

[Nuttyman54]

Originally Posted by tzjin

I'm a tad confused about why you feel a need to cool your CIM's that much.

Edit: See Kevin's comments above.

The team noticed in 2010 (the first year we ran with these speeds on the driveline) that during the quick turnarounds in eliminations, the motors started to get quite hot, and became much less efficient. I believe they were noticing battery voltage drops towards the end of every match. The driveteam took to fanning the motors between each match. They added the fans after the season, and saw a measurable improvement, especially at demos. Our robot last year used the fans as well, and they feel it's been very beneficial. Somewhere on CD is another post explaining this (by either Austin Schuh or Scott Bahl, IIRC).

I think that's all correct. One of the students could probably answer this better, but I think they're all busy packing and driving to Sacramento right now. I'm sure they'll add more detail later.

As a long distance mentor, I don't get involved in all the details of the robot, although I do know most of it. I've challenged the students this year that by the time they get to Championships (the only tournament I can attend with them) that they all know more about the robot than I do. Most of them are already there .

[kevincrispie]

Here's a link to Austin's post last year regarding the fans.

http://www.chiefdelphi.com/forums/sh...8&postcount=18

When turnaround time is faster during matches (practice rounds, elims, etc) the fans have their largest effect.

[JV2073]

Good Job at the Sacrmento and SV Regionals. You were amazing and we hope to see you in go far in national.
-Best of luck team 2073

[DampRobot]

Originally Posted by Nuttyman54

Thanks for the compliments Akash, the team is really proud of this one. This is the best picture of the transmission I could dig up is here.

Wow, that's a well done transmission! How did you mount the two gears to the CIM? Did you use the AM 8mm to Hex adapters, or broach your own gears? That's certainly a elegant way to get shifting with minimal complexity. By the way, are the center wheels direct driven?

[James Kuszmaul]

Originally Posted by DampRobot

Wow, that's a well done transmission! How did you mount the two gears to the CIM? Did you use the AM 8mm to Hex adapters, or broach your own gears? That's certainly a elegant way to get shifting with minimal complexity. By the way, are the center wheels direct driven?

We got a shaft custom machined to press onto the CIMs.
The transmission assembly is detachable, and it outputs in a 15 tooth gear which meshes with a 50 tooth gear which is on the same axle as the center wheel.

[Adam Freeman]

Another awesome machine!

As always you guys play so fast, its amazing. I am sure your drivers will be practiced up and ready to go.

I really like the horizontal belt system to push the balls over and line them up. Really cool way of solving the jamming problem.

I am really happy to see you are registered for the Championships this year. You had such a great robot last year, I think it would have been a big factor in the elims if you could have qualified for Champs.

Good luck this weekend.

[nlknauss]

Great looking robot and design process you all seemed to follow. After seeing this robot and others from CA it makes me want to take a trip out to visit the regionals sometime. Thank you for sharing the details of your machine with us! Good luck in competition.

Nate

[kevincrispie]

Originally Posted by Akash Rastogi

3. Any issues with balls jamming in the hopper/conveyor?

I think you realized this already, but we put in a horizontal conveyer to help sort the balls. Since we were going with ~24 in intake, we needed a way to rapidly get the balls into a column/row/whatever. Once organized, we can pretty easily get the balls into the tower. The vertical belt then runs at the same time as the shooter wheel, and presto, we shoot (and hopefully score).

Below is a picture of the conveyor.



The team spent several days prototyping this. Inevitably, a ball would get stuck somewhere. We configured it with the intake, then make sure we had accurate measurements in the CAD that were the same as the working prototype. Since it was such a key part of our game, we spent a lot of time on this.