Loading station trouble?

During the week 2 competition I attended, it was very apparent that teams were having unexpected trouble with the feeder stations. Every match had multiple gears piled up in the loading zone, sometimes exacerbating the feeding situation. Explanations were abound, from the height/angle being slightly different than the drawings, to the HDPE surface producing unexpected sliding behavior, to just downright poor visibility and tons of fuel in the way.

Some teams had no problem feeding- wide-mouth or actuating feeders were great! But others that expected deflecting panels to knock the gear into a narrow slot found themselves to be disappointed (slowly raises hand). Meanwhile, alliance members got frustrated with all the gears laying on the floor, clogging up the station.

No matter what the cause was, I am curious (a) if you had this problem, (b) your diagnosis of the problem, and © how you plan to fix the problem. (d) Do you think that as the weeks churn on, we stand to see less gears on the floor?

[Thought this topic would be discussed more thoroughly, but a quick search didn’t return anything- perhaps I used the wrong keywords, OR, are teams hiding their upgrades from unsuspecting first-time competition goers in the later weeks of the season??]

We totally had this problem. While setting up for our week 1 FiM home event we knew right away that the gear loading station was going to present a problem. Much much slicker then expected and the gear flies down it… even though we purchased a slick piece to put in our practice element. We struggled in a few matches and spent a lot of time modifying the gear piece. Luckily we got it down by elims.

This week we are at a week 3 event and spent a lot of unbag time improving the gear mech even more… along with other parts of our bot who at one point was completely disassembled at unbag (you can see in the instagram link below). It has created a lot of on the fly mods for teams.

Another thing I noticed teams having to make on the fly mods for was the climbing rope- expect it to be swinging when you want to grab it and remember you have to climb higher than the practice field.

All I can say is floor gear intakes are great.

I think they are helpful in district play and early weeks but as teams stop dropping gears and the field gets more cluttered with fuel as more shooters start to become needed- they will not be as helpful in high level play.

Gear intake are the most useful when teams drop gears at the airship. Something that will be prevalent through this entire game.

we intitially had trouble because our hopper is made of polycarb and we have a passive gear intake mounted on the side of it. We were expecting the hopper to act as a backboard and guide the gear into the pickup, but what actually happened was that the gear came down, compressed the hopper wall and then was shot backwards away from the robot.

We just made the walls of the pickup way higher, which worked for the most part until one of our elimination matches in which 71 gave us a bit of a love tap in the middle of the match at around 1:45

(That match was a lot of fun)

Ditto, it’s the best decision we made this season.

Ground feeder FTW!

Our cycle normally passes on the Key side of our loop, one way or another. We see the gear on the camera, center it, and approach. If the feeder station is clogged, we grab them. We can reach the vertical ones too.

The issue with the bottom of the ramp being at 25.5" not 25" is not isolated. At MISOU, that was one of our problems.Even worse is that multiple times, one of the legs supporting the chute ended up sitting on the lip of the wall, elevating it even further.

At our week 1 event we found the chutes to be 26.5" from the floor.
For some reason this caused the gear to drop in front of our robot. After reviewing the chute footage (we record Auto and gears) we cut off part of our gear handler and made it hinge forward. We haven’t dropped a gear since.

Our team spent a lot of time thinking about the dynamics of the loading station. We knew that there would often be gears or fuel littering the field, so we designed it to be optimal from a bumper distance of 5-10" away from the feeder station wall.

Generally this worked great, but if there was no litter on the field, the gear catches on top of our hopper and we need to back up slightly to get the gear to drop in. Sometimes the gear would fly right over our hopper and slide down the back of the robot.

Our original thought was to use software magic to ensure that our ideal loading position of 5-10" away is reached, using ultrasonic distance sensors and encoders to “step back” as needed, but the reality is that gear cycles go so fast that there is very little time to “park” perfectly. One mentor jokingly suggested that we should just attach a piece of fuel to the front of the robot to guarantee that distance :stuck_out_tongue:

We’ll be tweaking this between competitions to see if we can get a fast and reliable “step back a bit” to work.

We have a ground intake, but it’s beneficial for us when the gear lands in a certain spot. At AZ-North, the material on the chute was definitely slicker. I would push gears out at what I though was a normal speed, but the gear would always come out fast enough for it to catch on an edge and either flop or actually roll head-over-tails for a short bit.

To mitigate this, just practice spinning your gear as you push it through the slot. I think it’s the increased friction from the spinning that makes it move slower? Not sure what the physics are behind it, but the gear almost always lands flat in the center of the zone in this way.

So our passive gear mech had issues at the district event because the field at Indiana St. Joes event was built 3/4" too high (we were only catching the gear by this much), we measured it after a few matches. Our immediate fix for it was to get our drivers to back up when loading, which they got pretty good at.

At PNW Wilsonville, the blue feeder station was measured to be 26" while the Red was 25". This caused problems for a ton of teams, with gears either missing their gear mechanism and falling short, or in some cases missing the mechanism and going into their fuel tank.

The feeder stations are a tough lesson in tolerances. However, i doubt a 2" tolerance is what the field designers had in mind for these stations. Not sure what the measurement was at the district I attended, but oodles of people were annoyed with the “height differences.” And, who can really make the “account for tolerance” argument when you expect a 24" feeder height and for a 24" tall robot (in some cases)? 24.5" feeder = reasonable. 26" = ummm, now I have a gear in my hopper.

I completely understand about tolerances, and that the field will have variances and not be exactly as per the published spec. However, I am somewhat troubled when it is deemed perfectly reasonable to hold teams absolutely to the size specs and then allow huge tolerances on critical field element dimensions.

I an pretty sure the feeder geometry and robot size requirements were carefully chosen, to create engineering challenges. Given that, First absolutely knew that the feeder station height would be a critical dimension and variations could significantly impact team performance.

We knew that designing to the lower/wider size would create challenges, given that the spec already puts the lip of the feeder station 1" over our robot. Our design has a 100% capture rate for an in spec feeder, when we are positioned correctly, basically 1 ball diameter out from the wall. It has a solid capture rate even if we are right against the wall. However, if you raise the feeder an inch and a half (which is an insane tolerance) gears go sailing over the top of the robot. Yes we can compensate by positioning further away from the wall, but I am still disappointed by the high variability of the fields and expect better.

Perhaps the solution is to propose that teams are allowed to be out the same amount…:ahh: Raising our gear deflector an inch and a half would easily deal with this feeder variance. Designing a variable lip would be easy enough.

Yup, we’re definitely having some issues at CIR with feeder stations. Had two gears overshoot our catch mechanism.

Given how the field is assembled, I do concur there’s a decent amount of tolerance here that we didn’t account for. We’ve made some improvements which we’ll be trying out tomorrow, but…

It would be really awesome if FIRST was able to pick a couple crucial dimensions and provide tolerance info for them (and call field faults if the tolerance is violated during/after a match). I imagine this would not be trivial to implement, but it would be nice :).

For the most part we did not have problems with the gears falling into our mechanism itself. The majority of the problems came from the fact that the entire shoot was made out of poly-carbonate and thin pieces of aluminum which made it very hard to distinguish where the opening of the shoot was. Especially when considering that the drivers are wearing glasses, looking through the driver station wall glass, and then looking across a 50’ field at more glass…

But, to fix this we are switching to a floor gear intake.

I concur. As the level of play increases, the amount of dropped gears (especially at the airships) will decrease. We are seeing the rise of the shooters in week 2 and early week 3. Quals at large regional events where there is a lot of gear runners that do not have an active gearage will mean more dropped gears. Come eliminations, these teams will be left on the chopping block in favor of robots that can run a couple of gears and hit the 40kpa.