We have 20x15 foot piece of official carpet that we unroll for meetings and then roll up for storage. It is probably on its last leg (Falcon Swerve does a number on the carpet). It is hardly useable now since it slides and bunches up when we use it.
Is there any advice on how we can keep it flat and in place? We are thinking using a PVC frame to keep it taught or carpet tape. We would need to remove the carpet tape each time so we would be using lots of tape. The floor is linoleum.
At those dimensions I think PVC would need to be lashed to the carpet every few feet to prevent bowing.
If you could do the same with 2x4s you’d be solid.
At some point I tried to come up with a quick setup system made with these u-channels (McMaster):
We has a similar set up – the carpet would also slide around, and it was rough on the back. The net result was that it was very good at sanding floors, so we had to manage this also. The first few times, we noticed a whole lot of “sand” when we rolled up the carpet. The “sand” was actually ground up floor wax.
1072 set up 4x8 “carpet tiles”. The carpet is wrapped around the edge of a 4x8 plywood sheet and stapled on the bottom using carpet tack strip and nails. Works amazing and makes the carpet last longer.
If I had to make them now (other people worked on them last time) I would potentially skip the nail strip and just wrap over the edge and staple. Also maybe do thinner plywood, like 3/8".
Yes carpet is abrasive and I’m sure some of the “sand” you are seeing is the floor wax that has been abraded off. However the carpet will leave “sand” wherever it goes as it sheds the latex coating from the backing. I see it when rolling the carpet up off of our vinyl floor coverings or the concrete floor in the warehouse, neither of which has any wax.
In our case, there was very obvious damage to the surface of the floor – at least to the wax. Both the carpet and the floor will sand each other, so it’s generally a good idea to watch out for this.
Each tile is 4’ x 8’ made with a base of plywood, nail strips, and then carpet stretched over. The tiles are about 30 pounds each, I’d estimate, but they’re large and so they take two people to carry. We can usually lay about 26 tiles in 6-8 minutes with a team of 4 working on it. They’re really nice for the various configurations you can have the field in but one major downside was that they shift a lot as the robot drives over them. The field is 24’ x 32’ max size.
To address this, we built a “field frame”, a series of 2x4s like a photo frame stretching around the field and holding everything together. The frame supports two configurations, 24’ x 32’ and 24’ x 16’. The frame takes about 10 people and around 15 minutes to assemble, but we usually leave it down for weeks on end, only packing it up when necessary. Additionally, when packing up, we usually only take apart the joints that are absolutely necessary. We’re able to store pieces up to 16 feet long and so we only take apart about half the joints each time.
The tiles are about 1" tall off the ground and theres about a half inch discrepancy between the 2x4s of the frame and the field tiles. For this, we designed an inner frame and an outer frame. The inner frame is a series of beveled 2x4s providing a ramp from the height of the field tiles to the height of a typical 2x4. This makes the transition from the field tiles to the outer frame smooth, in case the robot happens to go over the edge. The corners of the inner frame are done similarly, with beveled pieces. The outer frame is built with a series of 2x4s held together with steel mending plates (link below). The corners are cut at a 45 degree angle and bolted together.
When setting up the field, we begin by assembling the outer frame while simultaneously laying out the field tiles. When those steps are complete, we push the tiles together and drop in the beveled pieces to make the inner frame and lock everything in place. The frame works well for the most part, the wood does flex a little and some gaps do develop between the tiles over time, but they’re usually small and just take a small shove to push them back together. The frame is significantly better than having the tiles shifting multiple feet apart every time the robot touched them. I’ve uploaded the best picture I have access to right now, but if you’re interested, I can get more detailed pictures of the tiles themselves and also the frame when we next put it out.
Thanks for the detailed reply.
I have a few follow up questions. Do the tiles ever develop wrinkles in the carpet that require the carpet to be re-stretched over the plywood? We are planning on laying these out semi-permanent so we were thinking of using 4 inch wide gaffers tape along all the tile seams to help hold the tiles together and provide a smoother transition between the tiles. Have you ever tested taping the tiles together and if so did it help?
The nail strips make it such that the carpets never wrinkle. We have gaff tape running around every tile to make the edges smoother. We haven’t tried taping the tiles together but we did try Velcro on the edges once upon a time. Personally, I think that laying the tiles out with Velcro on them is a huge pain because if they touch, then they stick, and its a massive effort to pull them apart, align them perfectly, and shove them together while keeping them aligned. The Velcro has pulled apart in some of the more extreme cases, but it usually holds together. I’m not sure if gaff tape will be strong enough to hold the tiles, there is a pretty good amount of force on them from the robot.
