Q: DDS real field hatch panel loader question

Question for someone with a real Destination Deep Space field.

On our field, our hatch loading stations are built to TE-19108. However, where the Frost King brushes attach to the plywood, it forms a ¼" rubber lip preventing easy removal of the hatch. So we would have to redesign our robot to lift up vertically a small amount before pulling the hatches out.

We’ve looked on the CAD of the real field and it appears that this won’t be an issue on a competition field.

So can someone with a real field confirm, if its expected to be able to easily — i.e. only through brushes —pull the hatches out of the loading station perpendicular to the plane of the arena wall without having a mechanism to lift them up vertically first.

TIA
K.C. 2834

Having seen the field up close in person, no one has an official field, this would be a good question for q and a, but from the best I saw, you are correct, the rubber bumps right up to the edge of the opening, but on the real field it does not overlap, but keep in mind the brushes are pretty stiff near the base where they are mounted so it still takes a good bit of force to pull the hatch panels out

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We have also come across this issue and are curious about what the actual field is gonna present come competition…

I don’t have an actual field, but can definitely confirm that the bristles are much harder to pull through near the keeper. Being able to lift the hatch panel half an inch, and being ready to extract asymmetrically (turning away from the station, rather than backing out) will reduce the forces required to load panels at the station.

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I agree, anticipate the hatch snagging on one side or the other, depending on which side of the field you are pulling hatches from.
Allow for pivoting a tiny bit as your robot pulls away.

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Good Idea. I’ve attempted to word it properly.

https://frc-qa.firstinspires.org/qa/238

Looking at the field drawings… part 19190 (the brush assembly) has holes 0.31" (5/16") from the edge away from the brushes. The plastic brush holder is 13/16" wide (measured in meat space), so the hole is centered 1/2" from the brush end of the plastic holder.

On the single brush side, this is mounted on part 19139, the Slot Stop. This has a pair of holes 1/2" from the edge of the piece, so it will line up with the brush holder edge. This piece is 1" thick and mounted directly to the loading station panel, so there should be no catch points on that side. Looking closer, I see that the 1/2"-from-edge holes are away from the brush. There is only 1/4" of Slot Stop on the brush side of the holes, so the plastic brush holder extends 1/4" beyond the edge of the Slot Stop.

On the double brush side, the brush holder is mounted to the slot cover (19133 on the right) which is 1/4" thick, and the holes there are only 1/4" from the edge of the slot cover. This means that the brush holder plastic extends about 1/4" past the edge of the polycarbonate. Further, the slot cover is offset from the loading station panel by three slot guides, each of which is 1/2" thick. There is no slot cover backing the brush, so there is a 1/2" thick gap behind the slot cover.

The hatch panel is 3/16" thick.

Bottom line: Unless there’s a problem with the drawings, there is definitely opportunity for the hatch panel to get caught behind both the brush holder and the slot cover plastic pieces on the dual-brush side. This does not appear to be an issue on the single-brush side.

A mechanism which could translate to one side (single brush side) and pull out on the other, then translate back would minimize the chances of getting caught.

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238 Hatch Panel Loading Station competition field design

Section 4.8.1.2 details the Hatch Panel portion of the Loading Station. We have built a model to the specifications of TE-19108 & the rubber fork of the Frost King brushes forms an ~¼" rubber lip requiring a vertical lift of the panels before they can be removed through the brush portion. We have examined the CAD models of the competition field and don’t see a corresponding lip. Is it expected to be able to remove a panel with only a motion perpendicular to the alliance wall?
asked 3 days ago by FRC 2834

LOADINGSTATION

Answer

Thank you for pointing out that there’s a difference between the FIELD version of the LOADING STATION HATCH PANEL dispenser and the Team Version.

It is possible to remove a HATCH PANEL from the official FIELD’S LOADING STATION without lifting it. TE-19108 performs similarly to the FIELD LOADING STATION (GE-19130 and GE-19155), but there are differences. GE-19138 and TE-19108-16 have slightly different profiles, which results in the HATCH PANEL on the TE version sitting slightly lower relative to the assembly. This means the HATCH PANEL is more likely to be caught by the lip of the bottom brush on the TE version than the official FIELD version.

Please look for updated Team Drawings and more information about this in Team Update 08 (link won’t be live until update published on 2/1)

During Kickoff, they very easily pulled it off by pulling straight out. I think that it will be the same on every field.

I wouldn’t call it very easy, in my experience it took a good bit of force to pull it out, to the point where a Velcro intake may have issues with the hatch panel getting pulled off by the brushes on occasion.

Time: 1:00:20

Dan takes off the hatch panel very easily and even goes on to explain how little force is used to pull them off.

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Ah miscommunication, I thought you were talking about pulling them through the loading station, not pulling them off the rocket, my bad, I thought we were talking about pulling them through the loading station, I was at the official kickoff, and got to pull one through with one of the field designers after I asked him about it, and it took a bit of force, once again not much for a human, but for a Velcro intake could be problematic if not maintained properly.