This will be the start of our pit build as we continue to push forward on progress ahead of the 2024 season. The foundation of these are road cases that are commonly used in the music industry but we’re adapting them to be used in the FRC district system.
Every item has a home and can be easily returned by any student/mentor
Vertical storage to increase open floor space
Fit in a FIM district pit (we commonly see less than 10x10)
Immediate brand recognition and overall branding at each event
Contribute to Winning every match
Functional space to field a competitive robot each match
Minimize wasted time
Like looking for items
Teach incoming student’s key skills that can be applied to our future robots
The Build – Hot Team Style
Fabrication Methods
We will use a lot of manufacturing methods that are not available to all teams but this pit could be built with other methods and achieve a similar result.
2.5 and 3D milling of tubing
Water Jet and Omio CNC for sheet metal
CNC and manual brake for precision bends
Printing via SLS, Markforged FFF, Ultimaker FFF, Prusa FFF
Welding via TIG and MIG (Spool gun)
Anodizing and Powder coating via sponsor
Design Style and materials
You will see a lot of sheet metal and tubing, two extremely common building methods on the HOT team. This small tubing size was chosen for space savings since we already minimized the footprint of the pit for our common events.
1” x 0.50” Aluminum for most of the structure
1” x 0.50” Steel tubing for horizontal bracing over large spans
1/6” 5052 Sheet metal bent, welded, and riveted together
1/6” 5052 Sheet metal for bracing/brackets
¼” 7075 Aluminum for heavy drawer support
PA6-CF, PC-CF, PETG, and Tough PLA used for printed brackets and supports
Off the shelf parts used for:
Lights
Slat wall
Mini Fridge
Casters
Latches
Hinges
Worktops
Case dimensions and concept layout
The Pit has a layout of 9’ by 9’ which leaves a little room for actives when we have larger pits available. Early student sketches and renders below that we used as idea generation to get full team buy in.
As we move into the fall, we have ramped up progress and secured our cases to begin our build out. Lookout for monthly updates and a final year-end post showing the completion and evolving improvements.
What are you doing for the dolly / caster plate under the road cases? Ours started with 3/4" plywood, but one corner of the dolly plate broke the first time it hit a curb We’ve since replaced it with a welded steel dolly:
At minimum, I recommend you use 20mm Baltic birch plywood for your dolly plate, which is a fair bit stronger (and more expensive) than regular pine plywood.
We worked directly with Nationwide Case in Wixom, MI to design the form factor and some robustness improvements to the cases. I can post direct contact info to them for those who are interested.
One of those improvements was to double up the bottom 3/4 thick plywood and increase the size of the extrusion that holds it all together. On top of that we plan to bend 1/8th 5052 into a hat section which will join the casters into a common plate. As well as provide a storage location for long stock.
We ran some initial studies and determined it would increase bending stiffness roughly 20x and torsional stiffness by 30x more than a single sheet of plywood alone. We were using a 500lb couple at the end of the hat section for this study.
We have some of the same concern. The casters are 5in, with 6.5in ground clearance, and the storage section of the hat is 3in leaving ~3.5in ground clearance. We benchmarked the clearance needed to clear the break over angle on our trailers ramp to get that number. Most cable protectors are 3in tall so worst case it would rub some. We wanted to be able to store a 2in polycarbonate tube on top of a piece of 1x1 in the hat section so it’s a balancing act
Short update but much bigger ones coming in the next few weeks. Manufacturing is almost all done, CNC folks finishing some of the last upper rack parts.
We did the final lower rack framing today, all final welded. Picture below of it on fixture table and then in the case with butcher block on top.
Next week we will have both upper racks test fit and sent off to powder coat and anodizing with our lower rack. This is the stage where all the work finally starts to show and things go together well…hopefully .
We’re long overdue for this update: things happened. As we end the year, the end is also near on these road cases being competition ready. Pictures below of progress:
Final…final? Update for a bit. Drawer face foam is done and just need to install mini fridge now. Welcome to the HOT pit for 2024 and beyond! Feel free to stop at comps to check it out.
Final Features:
Milwaukee packout for all fine organization
Clear bins on side case for bulk items like control system parts
5G internet for Pit streaming and scouting master uploading to server
12 robot batteries all charging
Built in pit computer for streaming, music, programming, scouting
Looks really good, I would have loved to do something like this if we had the space to and means to safely transport it to our venues.
Any plans to Kaizen foam the tool drawers rather than use the egg foam to keep tools in place while you travel? It’s also good for a quick visual on missing tools.
Yes, we just ran out of time The egg crate foam was an inexpensive lining and lets us play with where things live throughout the season. Once we like it we will look into some kind of shadow foam, more than likely after April
Looks great and thanks for sharing it with us.
Could you share a bit more about the drawer faces/foam?
It looks awesome, but other than looking awesome, I don’t understand the purpose. (Not that looking awesome is not enough purpose, but I wonder if there’s something more to it as well [like anti-vibration/damage in transit, etc].)
Could you also share a bit about the stack-up of the foam (is the multi-color a backer of red and a CNC front of grey foam)?
After going through a season with it, anything that you’d change (other than shadowing the tools perhaps)?
Sure! The foam was an idea from a few of our mentors. Its generally used as boat flooring. It comes in a roll ~6mm thick and two color bonded. So the top 3mm are grey and the bottom 3mm are red. We just put it on our router to cut out the grey to show the red from underneath.
The material itself is an EVA foam with adhesive backing, ours is from a company called Marine Mat. We decided to roll with it mainly because of its durability when used on boats over multiple years, and our ability to customize it how we want.
If I were to do it again, I’d never make custom drawers. We did a lot of custom work (welded frames, bent one piece sheet metal with welded seams) to fit what we had in an 8.5ft x 8.5ft pit due to playing in districts. Ultimately I would rather have used some of the 19in server rack drawers that I’ve seen some other teams using. Other than that the pits worked out great for us this year and we were really happy with the upgrade.
Do all the part organizers and totes stay in the rotating shelves while you rotate the shelves up and during travel? if they do, how hard is it to rotate them up when everything is all the way loaded?
The red part organizers are Milwaukee packouts, which have a locking feature integrated. We just cut the opposite portion of the pattern into sheet metal riveted to the racks. So they lock in for when the top flips down. We use a cargo net to retain the clear bins for transport
We’ve since replaced it with a welded steel dolly:
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The egg crate foam was an inexpensive lining and lets us play with where things live throughout the season. Once we like it we will look into some kind of shadow foam, more than likely after April