Re: Goalie Bots
 

I'm personally surprised to not see these goalies have tails and utilize the 20" extension. One of the worst things about a penalty shot in soccer is you have to stay on the line. In our case as long as your in contact with your carpet you could move much further into the playing field, thus cutting down the angles on the shot. If designed right, your blocker could be as far as 3 ft from the goalie line.

I don't follow. Couldn't you just have a cover (like 3 sides of a cube), that you put over the goal. If the cover was 20" x 20" x 20", I don't think anyone would be scoring on that lower goal.

Re: Goalie Bots
 

Unless a robot was purpose built for this specific task, I do not expect this functionality to be seen at all this year. Not really a "just have a" mechanism. This does not change that it is impossible for a robot to block the 10 point goal above the 1 point goal.

Re: Goalie Bots
 

That's also a near impossible shot to make if a goalie is blocking as far as they can over. That shot would have to be shot probably within an inch or two (someone else can do the math if they want) to make it without hitting the goalie or the side of the goal. Setting up that shot will take time, which achieves the goalie's point, to take up your time so that you can't do as many cycles.

Goalie Bots
 

I think it would be possible to make one in that time with a little bit of hard work, it's a pretty simple set up with a little problem solving to make sure it's legal and stable. If you do get it done, please share, I'd love to see how it turns out. Eli2410 knows more about it though so he's the one to ask.

Re: Goalie Bots
 

I'd say it depends a lot on how precise you can machine parts, how much time to work you have, how much weight you have to spare, and how quickly you can get supplies. If one of these four factors is on the bad end, I don't see it happening. If all of these factors are in your favor, you may be able to do this.

Re: Goalie Bots
 

As one of the group that decided to pick 4854 for our alliance, we where hoping to get a block during Auto, but no luck. Although they did get close. More time and thoughts we might have been able to get blocks during autonomous. Time to better calibrate I think we could have had them blocking shots. If we could it could have really swung the matches.

Most of the time they had good driving to shut down 33. We had watched them in multiple matches drive very well and shut down a team and even alliance. With one ball out there, if a driver plays well it can really slow down an alliance. Its unfortunate for us in those matches that both us and alliance partners died a few times. I think a lot of people where surprised by the pick (Ranked 37 of 40) but after watching realized why we made the pick.

Re: Goalie Bots
 

Can't the 6" cylindrical projection upwards be on the 20" horizontal projection, thus covering the area above the 1 pt goal?

Re: Goalie Bots
 

I don't see why not, but that would be a complex mechanism to make, and as far as I know no one has.

Re: Goalie Bots
 

Almost impossible, what are you taking about? Unless the goalie is extending outward 20 inches AND the extension is nearly 60 inches tall this shot isn't being blocked. And at this point, we are talking about a hypothetical robot with multiple complex purpose built appendages. This robot doesn't exist. Not that it couldn't, I guess, but it's a huge investment, not trivial.

An extension above 60 inches cannot be there as I believe the 1 point goal is not the goalie zone. Clever, but nope.

Re: Goalie Bots
 

If the "there" in that sentence is refereing to over the one point goal than I don't see how the rules prohibit that.

As long as a robot is touching the carpet in the goalie zone their 6" diameter blocker can be anywhere they can legally reach.

Re: Goalie Bots
 

Not without getting a 50 point penalty for possessing their opponents ball per Q&A 170

Q170

Q. Regarding possession of opposing alliance's ball: If a robot is attempting to score a 1-pt goal, if an appendage of a defending robot either a) holds the ball from dropping into the top of the goal or b) causes the ball to be "pinned" as it's pushed in the front goal, would it be illegal possession?

A. Yes.

Re: Goalie Bots
 

That's what I got from it too. The more interesting challenge is designing a mechanism that can a) extend 20 inches past the frame perimeter, and b) withstand repeated impacts of the ball at the very extreme of 20 inches out and probably at least 40 inches up.

When we were considering a pure goalie, we wanted to exploit the fact that the rules actually don't impose any height restriction at the beginning of the match, so if you start in the goalie zone, the blocking post doesn't even need to be retractable, which means the vertical blocker can be pretty strong. We also designed a two-way horizontal linear elevator based on 118's 2011 robot, which would have easily been able to take the impact of a ball. However, the weakness we encountered was that the goalpost acted like a wrench, with a huge mechanical advantage.



We stopped working on it around then because the mentors wanted to build a very different robot, but by then we had figured out that a blocker that could extend over the low goal is a major feature, and would mostly dictate the rest of the design.

tl;dr In my opinion, extending over the low goal to block the ends of the high goal is a difficult feature to implement unless the entire robot is built around it [and even then, it wouldn't be easy].

EDIT: Ooops, I forgot to mention: team 1710 executed this beautifully, and because the axis of the hinge is perpendicular to the torque above, they can easily withstand the impact of a shot. Bravo to team 1710!

Re: Goalie Bots
 

Re: Goalie Bots
 

I want to believe.

http://www.chiefdelphi.com/media/photos/39587

Re: Goalie Bots
 

You could still cover the "front" and "side" entrances to the low goal, and I think that very few robots are well equipped to shoot the ball into the top of the low goal.