FRC 95 The Grasshoppers 2019 Build Thread

Does the hatch mechanism just freely pivot, or is it spring loaded to return to center at all?

Freely pivots. There is no spring return right now, but we may add some sort of centering springs in the future.

Check for autodesk updater running in the ds. Or really any process like that. Ideally nothing else is on your ds.

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Thanks for the build thread, really like being able to stay up to date with the team while I’m away. Best of luck this competition season I’m sure you guys do great with that beautiful robot.


Elevator support guy-wires are in.

Ground collector is mounted and beginning testing.

Hand-off geometry looks good.

We’re a little worried about ropes coming off their pulleys with our new routing scheme, so we’ve designed and starting printing these handy little guys.

We’ve also started printing these umbilical guide rings to manage the wire/hose run that will go the carriage.

The cargo loader assembly is… not going as smoothly as we’d like. Hopefully we’ll have that running by the end of the week.

We’re at 92.6lbs as it sits right now with all hatch mechanisms, but no cargo and no HAB 3 climber.


We printed 2 of your lifecam housings - they are beautiful! Thanks so much for sharing the CAD!

Matt - 5675


Nice guy wires!

Based on the cable routing for your elevator, it looks like it only lifts in the upward direction and relies on gravity to pull everything back down?

That is correct.

Thank you for sharing! The student who designed it is ecstatic!


Are the guy wires used to support the elevator as a replacement for metal structure? Is the only benefit weight savings?


No. It allows for more clearance to adjacent mechanisms and wide mounting flexibility

I just wanted to say that following this thread has been a blast, and we really enjoyed working with you guys last year at Fairfield. Hopefully we’ll see you guys at NECMP, good luck! - 7127


Great progress today, although we’re not finished.

Skids, umbilical, cargo collector, jack guides, and other sundry mechanisms have all been added. We’ve tested the hand-off from ground collector to elevator for the hatch, seems to work nicely.

Another coach is going to send me some video from today, I hope have that posted soon.


Have you guys tested the over-center linkage yet? Any video?

We haven’t actuated them under air power yet, but as-mounted they both go just over-center and lock up nicely. I hope to have that sorted and tested on Monday. We likely need to arrange some spreaders for the guy wires to get everything cleared properly.


FYI - We are still doing our endmill giveaway.

Here is the product page.

JHH2500V is 99% of what we have to send out.

Here is a demo video (we have posted before) of using the mill in 6061T6 aluminum on a Tormach.

Shipping via flat-rate envelope is $7.50, so $8 via PayPal as goods/services covers it and accurately captures your shipping information. If you want to send a few more bucks for our Saturday donut fund that is always appreciated. Just shoot me a PM for my PayPal ID. I’ll send somewhere between 5 and 10 end mills with each order depending on demand. You can get mills more than once of course! This is an ongoing giveaway because these are cast-offs from my company. They have machined a little bit of carbon and are deflecting an extra 1-3µm now, so are worn out for our purposes. For FRC/metal purposes they’re basically new.

Can these endmills be used on a CNC router? My team usually uses single flute endmills of similar size and I’m unsure what the extra flutes mean in terms of functionality for us.

They can theoretically, depending on machine limitations. You should need to feed faster than a 1 flute I think. They are spec’d at .0005 to .0015ipt in aluminum.

It might help to know what speeds and feeds you are running in that demo. Where can I find more information?