pic: 2877's 2016 Robot

Here is a look at our(2877,The Ligerbots) 2016 robot. Our robot can successfully navigate all defenses except category C, including the low bar. We have a 6 CIM, 2 speed drive train and tank treads. Our intake uses 3d-printed rollers and polycord, and is powered by a bag CIM. We have two easily interchangable wedges, for the portcullis and CDF. Our shooter uses a catapult design to shoot high goals, and has servo controlled flaps on the end for shooting from variable distance.
We will be competing at WPI and BU district competitions.
Reveal video to come
Good Luck, and see at the competitions!

I see you’re sporting some of that good old Tank Chain there.

See you guys at both your events!

Looks like you have a lot packed in there!

Best of luck this season… I’m eager to see you guys build on your last two seasons.

Looks very cool, what material are your 3d printed rollers?
Also if you know, how much do they weigh and what machine did you use? They look great.

The rollers are made from PLA, and the weigh ~0.5lbs. They were made on a mentor’s custom built, polar-coordinate printer that can accommodate tall prints like the rollers. They took 12-14 hours to print.

Awesome use of servos.

How did you fuse the poly???


A problem, by the looks. Something about an articulated frame perimeter, or stuff being outside the frame perimeter.

Ahh. I knew I forgot to mention something. This picture was taken 3-4 days ago, and since, an actual frame perimeter and bumpers have been mounted on. The actual frame perimeter is a bent plate that has been stood off from the 8020 so that there is a 1/4" gap between the plate and the treads.

Some of the poly-cord may have been fused in the making of the 2012 robot. See maxwellfire’s answer below for more detail on poly cord fusing.

I’m confused are you saying you used parts made for your 2012 robot or am I reading that wrong. As an LRI I’m hoping I’m reading that wrong.

Are you saying cutting and re-welding polycord that was used on an old robot is illegal? Wouldn’t used polycord (if you cut out the previously welded part) be almost indistinguishable from new polycord?

The Polychord is not the same chord as what was on our 2012 robot (it’s a much smaller diameter in fact). We merely took inspiration from our 2012 intake. I think Mammaloon is a little confused :P.

despite that, I didn’t think that it was illegal to reuse material from another robot, especially if its dimensions/length was changed.

To bond the polychord we made a wooden jig and then used a lighter held underneath to heat the chord until it became liquidy. It took a lot of bad joins to come up with a method that actually worked (if anyone is interested I’ll share the specifics)

Awesome use of servos.
Thanks! We hope to be able to use them to angle our shot consistently. (maybe even some left to right aiming if the programmer are up to it :D) We currently have new servos on order since the 12 dollar no name ones we were using kept dying… We went with a hitec hs85mg.

Also, to add more specifics to Mammaloon’s answer about the printer, it’s a modified Kossel delta printer. They came out really nicely. We have a lot of printed mounts and other things on our robot this year. It’s really nice what flexibility it gives you.

If they used the fused portions from the 2012 robot then yes it would be illegal. The previous comment said that the cord was fused for their 2012 robot, those connections would be illegal.

nice beaver tail