Gaps

antmatts
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Re: Gaps

Post by antmatts »

nicksalanitri wrote:
nicksalanitri wrote:My partner and I close to finish building a design that will have up to 80-90cm in gap distances, has anyone seen one with anything more than this or do you think we'll be good for most tournaments i,e. Cornell, NY States, etc. Although this does have consistency issues.
(I edited this after i had my tech day and realized how inconsistent 100cm was.
That is the highest number for gaps that I've seen yet. What kind of ball did you use?
JionPark
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Re: Gaps

Post by JionPark »

antmatts wrote:
nicksalanitri wrote:
nicksalanitri wrote:My partner and I close to finish building a design that will have up to 80-90cm in gap distances, has anyone seen one with anything more than this or do you think we'll be good for most tournaments i,e. Cornell, NY States, etc. Although this does have consistency issues.
(I edited this after i had my tech day and realized how inconsistent 100cm was.
That is the highest number for gaps that I've seen yet. What kind of ball did you use?
Isn't there a maximum amount of points you can only get for gaps?
antmatts
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Re: Gaps

Post by antmatts »

sandvinsd wrote:
nicksalanitri wrote:Does anyone know the best ball to use (size or type), the ball I am using can only get me about 29-30cm of gaps. With this distance do you think that placing is possible in the New York/Pennsylvania area tournaments? Max score overall possible is about 240.
It would have placed about 3rd to 5th in the three SoCal invitationals that I am aware of. Steel marble about 4mg of weight.
For the weight of the marble, I just wanted to clarify whether the marble is 4 milligrams or 4 grams. Thanks in advance!
Crtomir
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Re: Gaps

Post by Crtomir »

JionPark wrote:
antmatts wrote:
nicksalanitri wrote: (I edited this after i had my tech day and realized how inconsistent 100cm was.
That is the highest number for gaps that I've seen yet. What kind of ball did you use?
Isn't there a maximum amount of points you can only get for gaps?

No maximum score for the gaps. There is a maximum number of gaps you can have though. It's 5. However, each gap can be as wide as you can make it. I don't know how some folks are getting 80-100cm of gaps. There is a direct correlation between vertical drop distance and horizontal jump distance. Theoretically, if all potential energy was converted to kinetic energy (velocity of the ball at jump), the horizontal jump range would be twice the vertical distance the ball falls (or rolls) before the jump. In reality, there are other effects that destroy efficiency such as friction, energy being converted into rotational energy of the ball, and so forth, so that the relationship between vertical ball drop to horizontal gap distance is much lower. Our kids did some exhaustive experiments and found that even with the best track curves, they could only get a maximum gap distance that was about 0.95 times the vertical distance the ball drops down the track before the jump.

Now you factor in the maximum available horizontal distance which is the diagonal of the 60cm x 60cm box. That ends up being about 84cm. You need a certain amount of horizontal distance for the track leading up to the jump (say 15cm). Then you need a 5cm of track to catch the ball on the other end (as per the rules), then a few more (say 4cm) to turn the ball or be the finish area. That makes a maximum horizontal jump of about 60cm using about 65cm of vertical drop on the curved track before the jump to get the necessary speed. To get 40cm more of jump, you would need about 40cm/0.95 = 43-45cm of additional vertical drop, unless you can somehow maintain the speed of the ball after the first 60cm jump.

The point is, I'm not seeing how teams can get 100cm of gap distance AND still get close to the target time. To get long jumps, you need high speed. To get long times, you need low speed. These two are diametrically opposed to each other. Unfortunately, the rules are biased toward the gap score way more than towards the time score. It almost doesn't make sense to try to have a long run. All your effort should be in trying to get the maximum gap score. In other words, the rules turn this event into an Air Trajectory like event.
wellOKthen
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Re: Gaps

Post by wellOKthen »

Who here has the most gaps? does anyone here have more than 50 cm. of jumps ?????????
cool hand luke
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Re: Gaps

Post by cool hand luke »

we have 65-70 cm of gaps. We are trying a new design this weekend that may give us another 30 or so.
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Re: Gaps

Post by cool hand luke »

Crtomir wrote:
The point is, I'm not seeing how teams can get 100cm of gap distance AND still get close to the target time. To get long jumps, you need high speed. To get long times, you need low speed. These two are diametrically opposed to each other. Unfortunately, the rules are biased toward the gap score way more than towards the time score. It almost doesn't make sense to try to have a long run. All your effort should be in trying to get the maximum gap score. In other words, the rules turn this event into an Air Trajectory like event.

why not go both fast and slow. Get fast to get the jumps, then slow it down to get the time.
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Re: Gaps

Post by Crtomir »

cool hand luke wrote:
why not go both fast and slow. Get fast to get the jumps, then slow it down to get the time.
True, but there is a limit. To optimize your score, you basically just want to get the maximum total gap distance. Then, with whatever vertical space you have left over (and this should be minimized to get max jump distance), you try to slow the ball down enough to scrape out a few more time points. There really is no reason to worry about time or height scores. Everything comes down to how much horizontal jump distance you can achieve with a give vertical "drop" distance to get the speed up for the jump.
kylg
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Re: Gaps

Post by kylg »

You can actually get more horizontal jump distance than vertical height. The most I have gotten is a 28cm gap with a 23 cm tall ramp.
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