In last week’s competition, we noticed that we were leaving black marks on the field from the black neoprene traction treads on our MK4 swerve modules. The field wasn’t damaged, it just looked like someone was bad at coloring within the lines. The refs did not flag us for it, but could someone eventually hit us for that. We have the blue nitrile, but as several have noted they do wear much quicker. Thoughts?
Were you able to identify whether particular situations were resulting in the marks (i.e. pushing matches with other robots, bumping up the field elements/perimeter, sharp turns, high acceleration or sudden stops, etc.)? Did you ever have issues with the steering angle of one or more of the modules such that you might have been dragging a wheel? I wouldn’t expect tread to leave marks unless there was some fairly high friction forces between the wheels and the carpet. So, I would expect that there would be some cause for the skid marks.
If your wheels had lost traction with the carpet and were spinning at the time that you left the marks, then you might be at risk of causing the sort of damage that other teams have been flagged for (i.e. burning through the carpet). There are ways that you can prevent wheel skidding if that is the problem. But the easiest would be to just make sure that your drivers were aware of it so that they could avoid it (i.e. not pushing at full force into the wall or fender or other immovable objects on the field).
I can run your numbers through a drivetrain simulator to see if you would be expected to loose traction at stall if you like. In order to do this I would need to know the following data: what gear ratio of the MK4s are you running? What drive motors are you using? What is your total robot weight (full up with bumpers and battery)? Do you have any current limiters on your drive motors?
We have blue nitrile wheels and leave blue-black skid marks from driving aggressively all over our practice carpet. The carpet doesn’t appear to be damaged, and the marks appear to fade over time.
Just be careful not to melt holes in the carpet, that can get you dinged.
This has been noticed before…
Thanks. Looks like we had an issue with one of the swerve modules which we just replaced last night. Yes, we did put in current limiting on the spark max’s.
My question was more fundamental in nature. The field wasn’t damaged, it just has some black streaks on it. Was not sure if someone would consider that damage or not. Some of the marks were from pushing/defense.
See you at Campbell!
Since there is no clear definition of what constitutes damage, there is some risk of getting flagged. But what you are describing seems much more superficial than what other teams have actually been called out for. It sounds like (at least in NC) if the field crew or refs have a concern with what they are seeing they will bring it to your attention. The only card I think I have seen in NC for field damage was given in Asheville during semi-finals and the offending team had been given at least a few warnings prior to getting the card. I didn’t see the extent of the damage they were causing, but the field crew took the drivers to one of the spots and they spent some time assessing the damage so that the team understood what they were getting flagged for.
So, I think you are pretty safe.
I will not be at Campbell with the team, but I will be watching. Good luck!
The black tread definitely leaves marks ANYTIME there is scrub. Take a loose piece of tread and just rub it on the carpet. We had a SERIOUS problem with the black tread separating from the backing. You can glue it back, but it needs to sit 24hrs for a good cure. FYI: We were running a 4 traction 2 omni WCD.
Does anyone know how to clean black neoprene tread stains off carpets properly? The carpet that we used wasn’t exactly our’s, so to clean it we tried using a carpet washing machine with a basic solvent, but we had no luck in removing the stains.
It’s a deposit of the tread material, embedded in the carpet fibers. You’re very likely out of luck there; any solvent that will take it out will kill the carpet faster.
Occasionally, I’ve gotten away with carefully cutting out the affected fibers, but wheel skids tend to be a bit too large.
I believe that Troy is correct, unfortunately.
Modern FRC drivetrains are overpowered; they can slip high- traction wheels on standard carpet while geared for ludicrous speed. Add individual wheel heading control (swerve), and we have a recipe for full time drift turning. And thereby for permanent arc shaped skid marks all over the field. There’s no end to this in sight.
Many teams commented early this year that their practice carpets are toast. The same is now true of every official field carpet as well. The 2022 Robots vs. Carpets War wasn’t even close.
Is carpet the only good long-term field floor option, given this problem is unlikely to go away? What about 4x4 interlocking composite flooring squares or something that would hold up better against slipping wheels?
Hard type field flooring options is definitely something id like to see investigated if nothing else so teams don’t have to fully carpet an area to get a semi accurate idea of how a robot is going to drive.
Given the potential of a hard floor having a larger upfront cost (definitely an assumption as i’ve never had to look into flooring costs) I feel like it’d be smart to look for something that could be used for at least a couple years before having to be replaced as such having a material that doesn’t change its friction properties too much.
My one big concern with hard flooring is how slippery it would be. Currently is some grease flings off a gearbox onto the carpet it doesn’t change anything to anyone walking on the field. I don’t have any solid numbers but my intuition would say that this same grease or other liquids could lead to a slipping hazard for anyone walking on the field.
For now though what roll out alternatives to the current carper are there that are still cost effective? Is there some type of much more durable carpet that could be used or some type of roll out flooring that could be used?
Well if it can be used for a full season it would be much cheaper than the carpet.
The huge problem with a non-carpet floor is how would the field be held together? The carpet is the key thing that keeps the walls and game elements in place via Hook tape on the bottom of everything.
hmmm that’s compelling. Have some concerns about wear resistance of it and how easily it would bunch up.
Been thinking about making a test rig to see how well different materials stand up to black tread. Have some old rails from when we replaced them on our omio so might be able to use those.
Hard top field surface has been done before (the pebble-top field surface in 2009). If I recall it was laid on top of the carpet so the other field elements still attached with hook fasteners?