Storm the Castle B [TRIAL]

[bernard]

Storm the Castle is a trial event for Division B.

Storm the Castle Wiki
Past Threads: 2011, 2012

[Pebble]

What's a counterweight ballista, it's mentioned in the wiki but I don't know what it is.

[Northridge]

Too be perfectly honest with you, I was wondering that myself. Ballistas by definition are torsion based machines. They store energy in the limbs of the "bow." I suppose a counterweight version would store energy into the limbs with a falling weight. I have judge StC several times over the years, and have never seen this design.

[knightmoves]

There were designs for Scrambler that use the falling weight to stretch springs, and then used the springs to launch the car. Presumably you could construct a ballista along similar lines.

[Pebble]

There were designs for Scrambler that use the falling weight to stretch springs, and then used the springs to launch the car. Presumably you could construct a ballista along similar lines.

That sounds like it's not so much powered by the weight as it is the springs, but if this was allowed would it work by theoretically using the weight to pull something like a slingshot backwards (or a torsion powered catapult like a ballista or onager), and then somehow release it when it reaches a certain depth so that the arms spring forward and fires the projectile. Right?

[Northridge]

There were designs for Scrambler that use the falling weight to stretch springs, and then used the springs to launch the car. Presumably you could construct a ballista along similar lines.

That sounds like it's not so much powered by the weight as it is the springs, but if this was allowed would it work by theoretically using the weight to pull something like a slingshot backwards (or a torsion powered catapult like a ballista or onager), and then somehow release it when it reaches a certain depth so that the arms spring forward and fires the projectile. Right?

Many years ago, I saw a few designs like this when this was an event (I want to say 2006 season). The issues teams that did this had was demonstrating that there was absolutely no energy stored in the elastic before the weight fell, and that the release mechanism also contributed no energy to the launch. Because these devices looked so much different from everyone elses, they also appeared to be highly scrutinized.

[knightmoves]

There were designs for Scrambler that use the falling weight to stretch springs, and then used the springs to launch the car. Presumably you could construct a ballista along similar lines.

That sounds like it's not so much powered by the weight as it is the springs, but if this was allowed would it work by theoretically using the weight to pull something like a slingshot backwards (or a torsion powered catapult like a ballista or onager), and then somehow release it when it reaches a certain depth so that the arms spring forward and fires the projectile. Right?

For the scrambler design, the springs have to begin unstretched (and teams were expected to show that). All the energy comes from the falling weight, but the springs allow that energy to be transferred to the vehicle in a short snap, rather than spread over the time it takes the weight to fall.

And yes, I think you have it right. The way the scrambler designs worked was to use the falling weight to stretch the springs, and then to have the weight hit a trigger to release the vehicle.

[Pebble]

This sounds interesting. Do you know what their release mechanism looked like or how it worked?

[knightmoves]

This sounds interesting. Do you know what their release mechanism looked like or how it worked?

From memory, a trigger release as used in archery was quite popular. And the falling weight would pull a cord attached to the spring through some kind of ratchet mechanism.

[Pebble]

This sounds interesting. Do you know what their release mechanism looked like or how it worked?

From memory, a trigger release as used in archery was quite popular. And the falling weight would pull a cord attached to the spring through some kind of ratchet mechanism.

For this to work, I'm assuming that the weight is not directly attached to something like a string that connects it to the "sling" part. In my mind, I'm kind of thinking of it like a compound bow's cam except that the string attached to the "sling" has the archery device which is set off somehow when it reaches a certain point or if the weight hits something. I know this design is flawed, but did the actual thing relate to my guess in any way?