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Start Task

Posted: September 3rd, 2018, 7:19 pm
by Unome
See rule 4.a

Any challenge here is likely going to be in reliably triggering something with a weight as light as a Ping-Pong ball.

Re: Start Task

Posted: September 9th, 2018, 7:28 pm
by Brov
Does the ping pong ball have to hit the golf ball directly or can it release some kind of trigger which then hits the golf ball?

Re: Start Task

Posted: September 9th, 2018, 9:05 pm
by nicholasmaurer
Brov wrote:Does the ping pong ball have to hit the golf ball directly or can it release some kind of trigger which then hits the golf ball?
I look in vain for the word directly in 4.a... Since "causing" simply means to 'make happen,' I would expect indirect paths to be allowed. In contrast, the golf ball's movement must start the next action.

Re: Start Task

Posted: September 11th, 2018, 2:29 pm
by terence.tan
does attaching a string to the golf ball count as modification?

Re: Start Task

Posted: September 12th, 2018, 7:19 pm
by TheSquaad
terence.tan wrote:does attaching a string to the golf ball count as modification?
I’d say if you’re wrapping the string around it, that would be fine, since to me, modification means changing the properties of the golf ball. However, if you were to glue a string or run it through the golf ball (which you’d probably want to do to attach a string), that would be modification.

Re: Start Task

Posted: November 12th, 2018, 2:13 pm
by CookiePie1
We're having some trouble coming up with a reliable way to get the golf ball to move. We tried to use a mousetrap but it was really hard to get it to be reliable. Any ideas?

Re: Start Task

Posted: November 13th, 2018, 3:33 am
by TheSquaad
CookiePie1 wrote:We're having some trouble coming up with a reliable way to get the golf ball to move. We tried to use a mousetrap but it was really hard to get it to be reliable. Any ideas?
Drop the ping pong ball from above your device and have the golf ball near the bottom. The momentum gained from falling 20+cm will help a lot

Re: Start Task

Posted: November 26th, 2018, 9:45 am
by knightmoves
CookiePie1 wrote:We're having some trouble coming up with a reliable way to get the golf ball to move. We tried to use a mousetrap but it was really hard to get it to be reliable. Any ideas?
A ping pong ball weighs 2.7g. If you want your device to respond to the mere presence of the ball, you need to build a balance sensitive to that mass. That's doable, although you'd want to recalibrate it after transportation. If you build something that relies on the momentum carried by the falling ping pong ball, it needs to respond very fast, because the ball bounces.

Re: Start Task

Posted: November 26th, 2018, 3:27 pm
by TheSquaad
knightmoves wrote:
CookiePie1 wrote:We're having some trouble coming up with a reliable way to get the golf ball to move. We tried to use a mousetrap but it was really hard to get it to be reliable. Any ideas?
A ping pong ball weighs 2.7g. If you want your device to respond to the mere presence of the ball, you need to build a balance sensitive to that mass. That's doable, although you'd want to recalibrate it after transportation. If you build something that relies on the momentum carried by the falling ping pong ball, it needs to respond very fast, because the ball bounces.
We're using the force of the ping pong ball to help the golf ball overcome friction. After that, the golf ball's weight is all that's necessary to trigger the next action -- not the additional weight of the ping pong ball. We felt that making something like a balance would be too finicky to be reliable.

Re: Start Task

Posted: November 28th, 2018, 9:40 am
by annabelle0308
If the task says “drop” a ping-pong ball, would doing something more along the lines of throwing it downward into the machine be allowed?