Trajectory B/C

[sean9keenan]

I also think that we had to exceed the spring constant of our tubing in order to make the 10 meter shot. We avoided that by doing very few tests that far out. I think thicker surgical tubing or thicker exercise tubing should work well. If your surgical tubing has a high enough spring constant (which can be adjusted by using a thicker piece of tubing, or doubling it up) it should work just as well as exercise tubing.

Doubling up the surgical tuping definetly messed up our consistency. we had much better results with single tubing.

It will reduce your accuracy, because for the same fraction of an inch off (in pulling back the ball) with one tube you will have more power and therefore more error when you use two tubes. But. You might need two tubes to go the distance.

You could only add the second tube for longer shots?

[starpug]

many people just abused the fact there was one and posted hard to beleive scores

If you believe that why didn't you report it to a mod. Just cause something is hard to believe, doesn't mean it's false.

I think all he meant is that sometimes people get a score once... and then broadcast it to the world, in an event like trajectory if you test your device 1000 times, it is very likely that at least some of those scores are rather "unbelievably" good, even though they are true, even if they aren't likely to be reproduced in competition.

Luck if you will Or probability...

Of course... A good device helps

A score is a score I don't see why he's complaining

[Nemokid]

Hey, best scores?

We got 140

We had a team get a score of 88 at a "practice" invitational. it was a "practice" one because the West Ottawa one got canceled. but i think thats the best i've seen.

I also think that we had to exceed the spring constant of our tubing in order to make the 10 meter shot. We avoided that by doing very few tests that far out. I think thicker surgical tubing or thicker exercise tubing should work well. If your surgical tubing has a high enough spring constant (which can be adjusted by using a thicker piece of tubing, or doubling it up) it should work just as well as exercise tubing.

Doubling up the surgical tuping definetly messed up our consistency. we had much better results with single tubing.

It will reduce your accuracy, because for the same fraction of an inch off (in pulling back the ball) with one tube you will have more power and therefore more error when you use two tubes. But. You might need two tubes to go the distance.

You could only add the second tube for longer shots?

very true. we also have a bow trigger for our releasing mechanism, and it doenst work as well as it should.

[swimmmm]

me and my partner just changed the cup on my trajectory beacause the cup we used before was breaking but we already have data with the old cup.. do cups really change that much on the launching or should we redo testing? we still have like 2 more weeks so we still have time but im too lazy lol...

[zyzzyva980]

If you use a cup that is congruent to your old cup that should be okay.

[swimmmm]

If you use a cup that is congruent to your old cup that should be okay.

its not lmaoooo idek where we found our old one but the new one is like cut out of a foam cup and the base is taped with hot pink duct tape lmaoooo but its like... at least 3x larger =/

[AlphaTauri]

I don't think that's going to last that long either. If you can find a plastic beaker, cut it down to size and glue it to the arm, it works well and is pretty durable. The thing that you launch the projectile out of shouldn't really affect your results that much though- definitely not as much as other things (bungee cords stretching out and the like).

[Walton Science]

What constitutes the "plastic practice golf ball"?

and

What is the popularity/success rate of using a tube to direct the ball?

[andrewwski]

Practice golf ball is exactly that. It's basically a whiffle ball that's the size of a golf ball - most have holes in them, some don't. If you go to a sporting goods store you'll find them.

[jazzy009]

What is the popularity/success rate of using a tube to direct the ball?

it's arguably one of the top three designs used most frequently.
In other words, it's been done and can be done well.