pic: "You should never go against a robotics kid"

the trebuchet is probably also more relevant to the game then the fish also:rolleyes:

It’s a trebuchet with a twist


A torsion engine stores energy through torsion or twisting of something (usually ropes). The catapult pictured stores energy through the stretching of the surgical tubing, not twisting.

I agree Barry! I think, however, before the decision is made extensive testing is needed. I propose setting up a “splatter wall” and flinging all kinds of fruits at it to see which one makes the prettiest pattern. (oh yeah, and safest).

Dave, can you spare a banana or two? :smiley:

Catapult/trebuchet/launcher throws the fish across how far???

Hey, could you guys find an opah and launch it, just to relieve everyone’s stress around here (and discussion of the game hint)?

how did you make it realease on end of the sling at the right time? or was it just try-bend?

If you look closely at the picture on the right (the CAD does not have it) there is a piece of 1/4" aluminum coplanar to the main arm that has a slight V shape cut out. The release angle wasn’t perfect (was about 35 degrees I think) but it was good enough. And since it was luck that it went at that angle on the first try, the group decided to just keep it that way.

First of all, I don’t think anyone is “fighting” over anything. There is a polite, rational discussion going on as to the appropriate terminology to use when referring to this design. Precision with words is equally as important as precision in drawings, or in machining. Often it is more important!

But I do appreciate the humour in the statement.


I think we decided to call it a “Catachet”

Sounds French…

Or a “CAD-achet.”

my school security guards flipped out when we were test firing our robotic t-shirt cannon because they thought it was a weapon so we arent aloud to make stuff like that anymore lol. great job by the way… i sure wish i had one;)

Lol, that’s why you should usually let school admin know what you’re up to with stuff like that :stuck_out_tongue:

Our school actually asked us to build a t-shirt cannon for rallies, and they actually reimbursed us on the cost of the parts, so that was pretty cool.

RE: What it’s called?

First of all, I call it “cool”! :slight_smile:

Trebuchets were the ultimate development of the stationary flinging-arm military weapon, but by the 14th century they were being overtaken by early cannon. Since no one alive now speaks a 14th century dialect, we are unlikely to be using the proper name in 21st century English, especially since I doubt medieval siege engines used in probably dozens of different kingdoms, duchies, and counties were all called the same thing. I believe were are applying our modern passion for rigid definitions to devices created in a time where no such cladistic hegemony existed.

Not entirely sure but i believe the term was changed during the Mongolian rule of Central Asia… or at least the Khan or Seljuk Turks created a different type and changed the terms…:confused:

doesn’t a trebuchet have a mass one one side of its arm instead of surgical tubing?

Well, what people have been saying is that a trebuchet uses a weight and not a spring, so it sholud be called a catapult, but a catapult doesn’t have a sling, so it should be a trebuchet.

let’s just call it a “Catachet”

And the video should come soon, Bannanakin is (attempting to) upload it to Youtube.

I really hope that that CAD was not made in Inventor provided for FIRST…
(That may violate the EULA! Oh Noes!)
Sweet “Catachet” though!
Maybe our team should make an pneumatic catapult…

I don’t believe that would violate the EULA for the FIRST provided inventor. I haven’t used it in a few years, but IIRC it’s simply the educational version which means that the only restriction is that you are not allowed to use it for any commercial products (ie anything you would be making money off of). This is clearly a non-commercial product.

The CAD was made using a student edition of SolidWorks.