Team Update 15 (2016)

[maxnz]

What I'm wondering is how effective the new low bar will be at stopping boulders. In theory, the fact that there isn't a heavy bar at the bottom could make a difference.

[bkahl]

Originally Posted by Lil' Lavery

Based on what has been happening at work for me today, I don't think I can agree with you.

Originally Posted by Jared Russell

If there wasn't an arbitrary plastic bag keeping me from adapting to changing parameters I would be more inclined to agree

This is more along the lines of what I am trying to say, I think. No doubt things change, but in the real world things can be fixed RIGHT AWAY. We have a trash bag preventing us from doing the same.

[Jessica Boucher]

Originally Posted by bkahl

In that case, usually 'Recalls' or something of the like are issued to let manufacturers change or fix the issue.

A very significant parameter has been changed without giving teams proper, if any for those of uswithout practice bots, time to change their designs.

As an engineering student, I have gone through significant classes about design in regards to proper client and manufacturer relations, and how issues like this are handled in the real world. I assure you this is not of the norm, and that professional engineers would agree.

From a manufacturing perspective, sure. After 10 years in software, and especially my last 5 years in the cloud, I'm constantly building and working under Safe Harbor statements - I know things could change at any time and assume the risk in order to get access to cutting edge information and software.

I guess this stuff doesn't phase me anymore. The only constant is that FIRST changes their mind. If I can recommend anything, the best use of your limited resources is to adapt and move on.

[Daria Wing]

I heard that there were a lot of teams who were basically shredding the fabric on the low bar so I'm glad that they fixed it, however, will this cause some complications to things on top of the robots??

[RyanShoff]

My thoughts of 4mm thick heavy plastic strips getting raked over the inside of bot, swatting the cameras twice a cycle, are getting worse or worse. If they are stiff enough, they'll form a robot check valve out of the low bar. Once you are about halfway through and just one strip falls in the bot, you probably can't back out for any reason.

[BrendanB]

I'm not thrilled by this change but it was definitely necessary after this weekend including the removal of the bar. Something I noticed at GSD was the bar moving into positions that actually prevented teams from crossing through the defense. I'd rather have this than a jammed low bar.

We won't know what this new setup is like until we compete this weekend. Consider asking your FTA/field crew if you can test pushing your robot under the low bar to protect your robot and their field components from damage.

[Ty Tremblay]

Originally Posted by Jessica Boucher

From a manufacturing perspective, sure. After 10 years in software, and especially my last 5 years in the cloud, I'm constantly building and working under Safe Harbor statements - I know things could change at any time and assume the risk in order to get access to cutting edge information and software.

I guess this stuff doesn't phase me anymore. The only constant is that FIRST changes their mind. If I can recommend anything, the best use of your limited resources is to adapt and move on.

We're all aware that things change in the real world.

The point is that this is NOT what happens in the real world. What's happened here is that the requirements have changed after the product was delivered, the customer isn't allowing us time to implement the changes, and the customer still expects their product to operate.

[Lil' Lavery]

Originally Posted by bkahl

This is more along the lines of what I am trying to say, I think. No doubt things change, but in the real world things can be fixed RIGHT AWAY. We have a trash bag preventing us from doing the same.

The configuration management used in the real world prevents plenty of things from being fixed right away.

[Kel2498]

I was in charge of field reset for the Red Side of the field at Lake Superior, and using the bumper material instead of the black material was like night and day. I am struggling to understand why FIRST didn't go that route. Didn't anyone talk with people at the Regionals who came up with solutions on their own to see what worked and what didn't? To me, using bumper material is the quickest solution that won't affect team's performance. In addition, doing more thorough inspections will help a lot.

[Lil' Lavery]

Originally Posted by Kel2498

I was in charge of field reset for the Red Side of the field at Lake Superior, and using the bumper material instead of the black material was like night and day. I am struggling to understand why FIRST didn't go that route. Didn't anyone talk with people at the Regionals who came up with solutions on their own to see what worked and what didn't? To me, using bumper material is the quickest solution that won't affect team's performance. In addition, doing more thorough inspections will help a lot.

Define "bumper material"

The "black material" was Cordura. Cordura is also the bumper material recommended in the FRC manual.

[camtunkpa]

Not a fan of the change. We have specific safeguard designed around the fabric and pipe, but do not have safeguards for 8" wide strips getting into our shooter, pneumatics or wiring. Also not a fan of having to spend yet more precious team money on the defenses and finding a way to safeguard our robot.

[IKE]

Originally Posted by Lil' Lavery

Define "bumper material"

The "black material" was Cordura. Cordura is also the bumper material recommended in the FRC manual.

The stuff we had at Southfield event was different than standard Codura often used for bumpers. I am not sure what exactly it was, but it had a much higher tendency to pucker on relatively square corners.

From an inspection standpoint, we looked for sharp edges, but did not fully realize the damage that would be done by square corners. IE, Things that have been approved many years, were causing punctures and tears.

We did go back an work with teams to make their leading edges more friendly, and this helped greatly, but did not fully resolve the curtain issues.

[Nuttyman54]

Originally Posted by Lil' Lavery

Define "bumper material"

The "black material" was Cordura. Cordura is also the bumper material recommended in the FRC manual.

I believe everyone referring to "bumper material" is referring to the 1000D Cordura recommended in the Game Manual. That is a Nylon fabric. The low bar flap is Cotton Duck Canvas per the Field Drawings, and referred to only as "Cordura" in the Game Manual. Cotton is very different than Nylon.

We built our low bar out of the field spec Cotton Duck Canvas (Cordura brand). It definitely is much softer and much more liable to get caught on and ripped. We have practiced on both, and have ripped the Duck Canvas but never the Cordura 1000D Nylon.

I too am confused as to the reasoning behind not going with the more robust cloth method. It's possible they determined that even though 1000D holds up better, it still wont's survive an event. It's also possible that they could not source and fabricate enough flaps in time to get them to the fields (though I'm not sure why, there are Jo-Ann's everywhere).

I'm curious to see what the ruling is going to be when the first flap gets caught in a drivetrain or an intake wheel and disables a robot. Is that a field fault, does it warrant a replay? I hope FIRST is discussing this scenario with the head referees, because many teams will be loading in tomorrow that didn't plan for and don't have quick fixes to make their robot able to handle the new design.

[Foster]

Originally Posted by Ty Tremblay

We're all aware that things change in the real world.

The point is that this is NOT what happens in the real world. What's happened here is that the requirements have changed after the product was delivered, the customer isn't allowing us time to implement the changes, and the customer still expects their product to operate.

Oh welcome to MY world. Changing requirements is the bane of my existence, but they happen. It happens all the time not just in software world but in construction and manufacturing.

My favorite "when I was an electrician" story is about a couple that had more money than common sense building a custom home. Lots of custom wiring (power, speakers, TV, etc.) to match their furniture.

We went over the electrical plan with them (since they are paying by the outlet), walked through the shell to check all the outlets, walked through the rough wired shell to check all the outlets, walked through the wall board up (but not taped) house and checked one last time. And at finish time for good measure. All good, all signed off. (And we had done a nice job, no punch list)

House closes, people move in, phone rings. "All the outlets are in the wrong place" "???? you signed off on every step" "We went out and bought new furniture and now it doesn't match. You need to come today and fix it, we are having a party in 2 days and it needs to be done by then!!!!" /sigh


And to be honest, I feel bad about this change. From the Re: Removal of Low Bar Fabric thread

Originally Posted by Foster

.... [snip]

Not sure what the fix is, but polycarb sheet isn't it.

Maybe flaps/ vertical strips of plastic like you see on commercial freezer doors to allow entrance and egress, That would let the robot pass but stop the boulders. The strips would stay attached. They would need to run tests on entanglement.

So it's possible that they got the idea here. But I'm wondering if the last sentence isn't what happened, they ran some tests with a willing team (lots of people with second robots) to see what happened.

It's not like this is their first rodeo. Lets try to give just a little credit to the GDC.

[bdaroz]

Originally Posted by Foster

...
House closes, people move in, phone rings. "All the outlets are in the wrong place" "???? you signed off on every step" "We went out and bought new furniture and now it doesn't match. You need to come today and fix it, we are having a party in 2 days and it needs to be done by then!!!!" /sigh

The difference here is that you got the opportunity to fix it before the event (party), right now all we can do is stare at a robot in a bag that's going to need some major changes to guard the intake mechanism.

Sure, we'll have time on Thursday of our event, but we now have to take time away from other things because of this change.

If this was the only way to make this work, or there were no indications a single-"panel" solution would hold, that would be one thing. However, there are several comments from people who used 1000D Cordura as replacements and had far better results.

Honestly, I'd rather see the GDC just remove the flap completely than change it this much.