Re: Pre-Stop Build Scrimmages - What Have We Learned So Far?
 

Were they angle shots?

Re: Pre-Stop Build Scrimmages - What Have We Learned So Far?
 

Yeah we managed to get one up there from shooting from the ground one match, and our human player another match.

Re: Pre-Stop Build Scrimmages - What Have We Learned So Far?
 

First of all, excuse my typo of axle, which I can't edit now.

We are running a 6-wheel drive with a 1/8 drop on the centre wheel, with AM performance wheels geared quite aggressively for 15 and 7 ft/second (calculated including efficiency loss). Performance wheels are threaded for 10-32. Each wheel had 3 grade 8 10-32 bolts in them.

About 10 minutes into driving yesterday, we noticed VERY limp chain. Upon closer examination, we found that the entire sprocket assembly had sheared off of the middle wheel. All 3 bolts had sheared. We promptly replaced the wheel with the bolts ends lodged in with our spare, pulled all the wheels off, and added 3 more bolts to each wheel.

Today I drove just as aggressivly, and we haven't had any issues (at least not with the drivetrain :rolleyes:). I suspect they sheared when I was braking while downshifting, but I'm not sure.

Re: Pre-Stop Build Scrimmages - What Have We Learned So Far?
 

The goals were pretty tight so many bounced back all day long. When the shots got through whatever unfortunate team was in the middle got frisbees rained down on them as this video shows.

Re: Pre-Stop Build Scrimmages - What Have We Learned So Far?
 

I didn't see this earlier in the thread I think. Drive teams are going to have to become desensitized to frisbees slamming into their window a couple feet from their face from human players in the last 30 seconds, at least at events where a majority of the frisbees aren't ending up being used by robots.

Re: Pre-Stop Build Scrimmages - What Have We Learned So Far?
 

One of our primary goals at Suffield was to perfect our shooting angles for the 2, 3 and tower goals. That's what we were tweaking most of the day. We were pretty pleased with what we were able accomplish and have more up our sleeve for WPI and CT.

Re: Pre-Stop Build Scrimmages - What Have We Learned So Far?
 

Koko Ed - thanks for the video! Good driving on the part of your team.
One note: Your human players will not be able to feed the discs into your robot exactly as they did on the video. The feeder slots on a real field are not simple slots in the plexiglass; they have a covered chute on the driver's side of the of the feeder stations. So you won't be able to hold on to a disc as it passes through the slot.
Good luck!

Re: Pre-Stop Build Scrimmages - What Have We Learned So Far?
 

What penalties were committed the most? What do you think the reason of these bad matches was?

Re: Pre-Stop Build Scrimmages - What Have We Learned So Far?
 

there was a pretty small field and it seemed many robots were not complete (176's robot stood out. A former world champion and winner of several Blue Banners does not build a coffee table on wheels. they are probably still finishing up the competition bot) and thus did not score very well at all.
The match that stuck out to me was a qualification match where the blue alliance raced out to a 20 to nothing lead but lost the match 40 to 30 due to a pair of technical fouls incurred by the feeder by reaching their hands through the slot. There were a couple of other matches where there were more penalty points than points scored as well.

Re: Pre-Stop Build Scrimmages - What Have We Learned So Far?
 

Our practice field has the feeder station with the chutes on the slots so Hawa can get practice dropping the Frisbees into the robot properly.

Re: Pre-Stop Build Scrimmages - What Have We Learned So Far?
 

Excellent.

Re: Pre-Stop Build Scrimmages - What Have We Learned So Far?
 

What kind of pickup did you use?

Re: Pre-Stop Build Scrimmages - What Have We Learned So Far?
 

One thing @ Rally that stuck out was some teams sported some serious cannon that fired Frisbees at a shocking rate of speed. While FIRST has cracked down on Human Players unleashing an insane hail of Frisbees I actually wonder how soon is it FIRST issues a speed limit for firing Frisbees like they did with the robots back in 2006.

Re: Pre-Stop Build Scrimmages - What Have We Learned So Far?
 

I sure hope they don't....

Re: Pre-Stop Build Scrimmages - What Have We Learned So Far?
 

I don't think FIRST will issue a speed limit like they did in 2006. 2006 was the first competition with projectiles and I think the speed limit they enforced that year was more of a precaution than anything.

Unfortunately, I don't think there is a velocity that the frisbees can be effectively launched at that is also safe for human impact. That being said, if a robot at competition repeatedly shoots frisbees out of the field in an unsafe manner, I assume the refs will issue a warning followed by a yellow card for additional aggregious infractions.