Hardest Shooting Robots

FIRST General Forum
#37

My response to this whole thread is… WHY?

Basically it’s about trajectory. You want the flattest one so that when aiming, your shot is less dependent on the distance to target. This means the driver doesn’t have to worry about positioning of the robot and the software doesn’t have to calculate a firing solution as rigorously. Furthermore, the shot is less dependent on the condition of the game pieces. In 2013’s case, a linear trajectory was desired because math is hard. Take a look at video of 2013 in aerial assist- the same design philosophies were in use. On the FIRST Robotics Canada facebook page, they recently posted a ton of pictures of GTR East with a few close-ups of 2013’s machine. While I can’t speak too much to the development of the mechanism as I am in a purely advisory relationship with the team this year, I do know it required a number of prototypes and testing to see what the limits of compression, friction material and inertia were.

#38

Our robot competed at FIM Event Sterlish-Standing (Week 1) and during our auton, we got caught up on on of the defenses, with our shooter tilted up, with even more angle tacked on as a result of the defense. We are using a flywheel system with two mini-CIM’s to shoot the ball. Our autonomous shoots the ball after a certain period of time, so just before the auton period ended, the ball was shot and hit the ceiling, almost getting stuck in the rafters of the HUGE gym we were in. Pretty powerful shot. Not to mention that we may or may not have taken out one of the other drivers…

#39

For our shooter competition speed it about 45-55% power, ending up around 4k RPM.

However, we do have a ‘testing’ mode referred to as Airplane! for shooting balls 60 feet, scar- I mean impressing parents, and punishing underclassmen.

#40

This thread needs videos.

#41

Here you go!

#42

I gotta ask… what in the world are you using? I see mini cims and what looks like 6 or 8 inch wheels but like… We did testing with direct drive mini cims on 6 inch wheels and it wasn’t that powerful.

#43

We’re using mini CIMs geared up 2:1 with 6 inch wheels at 4-5 inches of compression.

#44

Were you aiming to kill innocent volunteers?
I like your shooter though. Btw, did the boulder from your reveal video ever come down or is it still in the ort cloud? :smiley:

#45

We shot into the stands a couple of times during practice matches (from the corner, over the tower, and into the top of the bleachers). Regarding our boulder, it’s supposed to pass Voyager tomorrow. :smiley:

#46

Aha. That’s what I was trying to get at with my (counter) intuition about dealing with factors affecting ball trajectory.

#47

We all see videos of shooters working, but at the NYC regional, I saw a lot of missed shots. thebluealliance.com has some great stats, but nothing on shooting percentages. Anybody have any real data on percentage of made shots in high goal?

#48

Just a prototype that didn’t end up getting used, but here you go: https://drive.google.com/file/d/0Bzxb6Sc9JUtgVGZsdXptd284WnM/view?usp=sharing

#49

The reactions in this video are fantastic.

#50

Our robot shoots pretty fast.
It’s 4 775pro’s with a roughly 2.5:1 reduction and 4" stealth wheels with the second set running faster than the first with a surface speed of 130fps. I believe we currently have just over 1.75" of compression. We decided to shoot the ball as fast as possible with as little compression as possible to minimize the effect of ball inconsistencies. In testing there has been little to no noticeable difference between new and heavily abused balls as long as there are no large chunks taken out

[Album] Imgur

At competition we were running the shooter at 60%
Match Videos:https://www.youtube.com/playlist?list=PLrE0JKMRgg6An0ZOt8CXQSRbiXWyekewe

#51

Unsure as to how powerful they were, but both 4488 and 3663 had issues with boulders rebounding out of the tower after their shots at their first events.

if you really want the kings of ridiculously hard shots, gotta go back to 2013 :stuck_out_tongue: the robot I remember best from that is 3711; this video shows it relatively well at the 40 second mark, but you kinda had to be there. when they shot, you felt it; http://www.thebluealliance.com/match/2013wase2_sf2m1

#52

How about a 200mph shot?

#53

Gratuitous slo mo FTW.

#54

Although not a robot from this year the most powerful shot I have ever seen was 159’s robot from 2014. It was a catapult and the power it had was incredible overkill. The catapult was powered by four 500lb springs. 2000lbs of force! 2000! :eek: It had so much power that one time it was triggered without a ball in the 'pult and the bot launched up into the air and nearly did a complete front flip. The best part about it is it scared the safety inspectors to death, so in order to pass inspection the inspector told us if a team member stuck their hand in the springs when they were extended and held their hand there for 5 seconds we would pass inspection. So a guy from our team volunteered and promptly put his hand in the spring. A spring that, if its mounts failed would slam closed and crush his fingers into oblivion. This robot still scares 159ers to this day, its power was legitimately terrifying.

#55

So a volunteer forced a student to put themselves in a risky, unsafe situtation in order to demonstrate that the robot was safe? :eek:

Am I the only one that fails to understand this logic?

#56

Nope, sounds like crazy people acting crazy.