Most unused defense of 2016?

[howdosheeplamp]

Since your alliance is forced to choose only 1 defense from each category, and your defenses should be as hard to breach as possible, it's seems clear that teams will pick the toughest defenses to cross. Some defenses seem harder to cross than the other in their category, and will probably be picked much more often than their counterpart.
What do you think will be the most unused defense of 2016? Personally, I think it'll be the rough terrain as it doesn't look like it'll slow down the enemy robots as much as the rock wall.
These are just guesses though, I have no idea what method of transportation teams are going to end up deciding on.

[Redo91]

Category A: Portcullis v. Cheval de Frise

The Portcullis allows for has one part to move, and can be contacted in on place, but it must be lifted over the height of the robot passing through. A short robot could possibly have a passive mechanism that allows them to drive under the Portcullis.

The Cheval de Frise could be contacted in one place if the robot was shorter than the width of three of the tilting platforms, but would require some finer alignment. CoG of the robot will need to have attention paid to it.

There is opportunity for one mechanism to be capable of handling both these DEFENSES.

Category B: Moat v. Ramparts

The Moat and Ramparts are two parts of the same issue, a robot's CoG and potential high-centering. Given a low enough CoG and proper clearance, a robot should be able to just as easily pass over either of these.

Category C: Drawbridge v. Sally Port

The Drawbridge and Sally Port are both interesting DEFENSES. They will be easily opened from the courtyard side, needing nothing more than robots capable of traversing the field. Trying to tackle these two DEFENSES from the front will prove to be time consuming.

These DEFENSES can be tackled relatively quickly with the ALLIANCE working together by having one robot open the DEFENSE and the other two robots come through.

Both of these DEFENSES will be time consuming for those that do not plan before the match. They will pose no issue for prepared ALLIANCES.

Category D: Rock Wall v. Rough Terrain

Remember how intimidating the Barrier from Rebound Rumble appeared? The Rock Wall is only a half inch taller. Teams that design for it will have no issue crossing this DEFENSE. Also, any robot capable of traversing the Rock Wall should have no issue with the DEFENSES from Category B.

The Rough Terrain would prove quite a bit more difficult. due to the varying heights and one and a half inch gaps between the tubing pieces, there are plenty of opportunities for robots to get wheels stuck or high center.

Low Bar

The Low Bar is straight forward in its method. If you are too tall, you have to pass by one of the other DEFENSES.

[Aur0r4]

FIRST can be pretty intentional with the details of their designs. That extra half inch on the rock wall might be more problematic than it would appear. The Barrier from RR was indeed crash-over-able but only just for most conventional / kit frames.

[GeeTwo]

Having spent two evenings looking for a drive configuration that can cross all of the "drive over" class B and D defenses (while also fitting under the low bar), I think there will be teams that have trouble with each of them. I expect the same of the moving class A and C defenses. I doubt that there's any one that will be so generally easier than its counterpart that any of the obstacles will be "unused".

Edit: especially not the moat, which is currently in the lead. That was the hardest one not to have some failure mode, whether high centered over one edge, nose-in, or high-supported by both ends.

Edit2: I managed (in drawings) to get a robot with 5" of ground clearance stuck in the moat, or at least prevented from continuing to move forward. That spacing between two tall thin walls stymies many of the patterns I tried that could traverse the other non-articulated defenses. Most of the designs that had no trouble with the moat got caught on at least one of the rock wall or ramparts or rough terrain.

[James Juncker]

If I could point out what I had said before in a different thread, http://www.chiefdelphi.com/forums/sh...hreadid=141458
People need to stop thinking that they need to select the most difficult defenses(at least for Qualification rounds). similarly the defenses will change drastically based on the robots that you are facing, as each team will have designed their robot for their specific defenses.

The longest traverse time from my estimates of any obstacle would be the Portcullis at about 5-15 seconds depending on lift speed as well as robot height. after this the next longest would be Sally Port / Drawbridge from the outside without inside assistance. these would take about 5-10 seconds. Low bar is about 2 seconds if you can do it and the terrain defenses vary from 3-7 seconds.

[Taylor]

Clever teams will be able to handle the defenses quickly and effectively. The biggest obstacle I see with the defenses is their physical size as visibility blockers.
I believe at early stages of the event, many teams will ignore the tallest elements (Drawbridge, Portcullis) to aid visibility. As strategies get more refined, alliances will then artfully place the Drawbridge and Portcullis in the line-of-sight from their own tower to the opposing alliance's perceived most powerful member's driver station.

[evanperryg]

I'm surprised by the number of people who think the moat will be underutilized. Basically any team with less than 2.5" ground clearance is likely to struggle with it. I'm a little confused by the term "unused," does this mean the defense to be the least frequently placed or least frequently crossed?

Personally, I think the defense that will be the least frequently crossed is the Cheval. It's probably the most sensitive of any of the defenses, and requires an amount of precision far greater than most of the others. A short robot, as Ri3D Redacted is trying to prove, should be able to get through the portcullis passively, so it could end up being a relatively easy defense for some robots. However, the portcullis also offers some awesome utility as a vision block, which may make it a great pick into an alliance that focuses on capture points.

[vhcook]

I'm thinking the drawbridge will get the least use, as it's a visibility blocker, easily opened from inside, and from outside requires a simpler motion to open than the sally port.

The portcullis is at least slightly transparent and is a harder obstacle to resolve, so I think it will get used more in spite of its height. The cheval de frise requires some specific design to deal with as well, so I expect the overall usage to be fairly even (and aligned with strategic knowledge of the opponents).

The category B and D defenses really depend a lot on the opposing drivetrain, so I think they'll level out.

[Hgree56]

After watching Ri3D videos multiple times, I feel like the moat will be the least used. With a 6WD that is powered in the center, you can climb over both bars easily.

[c.shu]

So far our Ri3D group has had the most trouble with the Rough Terrain obstacle. Most of the others are fairly easy to tackle with a good design, where with the Rough Terrain the different levels of blocks combined with the somewhat random placement of them can find you bottomed out a lot faster than you would expect.