1706 Shooter Reveal

Well, here is our shooter in its wooden prototype form. It uses a coil spring that would be found on a pickup truck, pulled back about 6 inches I believe for a shooting force somewhere in the area of about 5-600 lbs. In this form we pull it back using a come along, and then release it with a quick release clip.

I was talking to someone on the electronics team and he came up with the idea for a name, The “Aluminum Archer”. It’s not bad IMO.

https://youtu.be/sWY1oqVhQxk

You will have to find a producer for some automotive TV show and shoot him with your boulder. That would get you even with Jezza.

It looks like you have lots of power. Do you need that much power? Is it safe? Is it consistent enough? How large will the final shooter be and how much will it weigh?

I feel sorry for the robot that tries to block that shot.

You might find the following historical articles of interest for researching more naming opportunities.



https://en.wikipedia.org/wiki/Petraria_Arcatinus (bow powered stone thrower)

Haha! My thoughts exactly when shot 4 went off.

It looks like you have lots of power. Do you need that much power? Is it safe? Is it consistent enough? How large will the final shooter be and how much will it weigh?

Wow, haha. A.) Yes, this was the amount of force calculated to get us scoring the high goal. We may have to modify once we get a shooter on the bot, but until then those are the rough specs. You can never have too much POWAAAAAAAAAAAAA. B.) It is safe, sort of… I wouldn’t want to stand in front of it, but it has never come apart or exploded. C.) It is very consistent actually, again, we are still tweaking, but once we trim those guides a bit more, it should be even more consistent. D.) I’m not sure on the final design, although it is fairly compact, and is designed to sit in the middle of out bot, which is not that big if you watched the frame assembly video. Total weight, again, I’m not sure, but im gonna take a guess at about 15-20 lbs. I’ll try and get a better measurement today.

I feel sorry for the robot that tries to block that shot.

Same, ::safety::

Holy crap, chill.

That amount of power seems wayyyy excessive !!! Which means it is about perfect!!
Goes right inline with "if at first you do not succeed, get a bigger hammer ! "

Are you sure your shooter structure is strong enough to last a whole season? People have been seriously injured when changing the coil springs in their car and they were not using the proper equipment/techniques for compressing the springs. While it may be fun to build an overpowered mechanism, it is poor engineering practice. It will also cost you in terms of weight, space, reliability, risk etc. A local team had a similar shooter in 2014. It worked well but the team members were too afraid to work on it and they replaced it with a different type of shooter that did not use large springs.

That is a whole lot of power! I like it.

While in general I agree with your sentiment about safety - I do think the word ‘overpowered’ could be a bit of a leap if there goal was to fire the ball in as straight a line as possible. Maybe this is their goal…

-Brando

Impressive power.

Do you have a cable down the middle to keep the spring somewhat contained if it experiences a rapid unscheduled disassembly?

How accurate is this?
In shooting at the high goal from the safe zone long shot, whats the percentage?

We were beginning to wonder if anyone else had thought of this… We have been actively working with a linear spring launcher and have found great success. We originally planned to have a spring that could have easily replaced a spring in an ATV, but since dialed it back due to concerns regarding the entire thing blowing up. Best of luck in tuning that monster.

Like the power! We prototyped something similar for a linear puncher. Any ideas on how you’ll get the ball into it intake-wise?

WOW, and we thought our spring shooter was ridiculous! :eek:

We did the math as well and got a number closer to 200lbs @ 5" of compression, so with an extra 400lbs and inch of compression I can safely assume this thing shoots EXPONENTIALLY harder than ours! Good job ::safety::

If you’re both using springs it’s probably closer to linear (if you’re talking about force) or a power function (if you’re talking about energy). :slight_smile:

We don’t have a cool cord system like yours, just rollers on top. Then we won’t take the ball into the robot just hold it with the intake. Then we get the intake out of the way or we launch it through the goal.

I can see it now - THE TOWER FIGHTS BACK.
The boulder flies into the high goal…and ricochets back out.

Ok, things to fix!

Most important, our shooter is actually more in the neighborhood of 200lbs of force. I had in my mind that the spring was a 750, when it was really a 375. So, not nearly as much power as in the video or as stated.