Air Trajectory B/C

[laidlawe18]

I think that in theory, that would be ideal, but in all practicality, it's probably not going to work. My goal for this year is to make something that is super consistent, and can accurately be modeled by some kind of function. Rather than using physics to find a function, I think you'd just be better off just testing it a bunch and then making a regression equation. With the far target no longer on the center line, there are way to many individual places that the target could be to test and perfect all of them.

[windu34]

I think that in theory, that would be ideal, but in all practicality, it's probably not going to work. My goal for this year is to make something that is super consistent, and can accurately be modeled by some kind of function. Rather than using physics to find a function, I think you'd just be better off just testing it a bunch and then making a regression equation. With the far target no longer on the center line, there are way to many individual places that the target could be to test and perfect all of them.

For the far target, couldn't you just bring a laser pointer to aim your device and then use Pythagorean theorem to find the distance?

[laidlawe18]

I think that in theory, that would be ideal, but in all practicality, it's probably not going to work. My goal for this year is to make something that is super consistent, and can accurately be modeled by some kind of function. Rather than using physics to find a function, I think you'd just be better off just testing it a bunch and then making a regression equation. With the far target no longer on the center line, there are way to many individual places that the target could be to test and perfect all of them.

For the far target, couldn't you just bring a laser pointer to aim your device and then use Pythagorean theorem to find the distance?

Yes, but the problem is that you're going to get numbers like 6.243237 or something. It is impractical to test every single possible distance, because there will be so many this year. Having some kind of function for weight or height dropped from in relation to distance would be much more practical.

[SPP SciO]

I didn't see anything in the rules prohibiting laser alignment (unlike scrambler, for instance), so I imagine it'll be a simple Pythagorean calculation, and I imagine the hope is that the graphs will actually be useful!

Speaking of graphs, rule 6.c.v seems a little weird - only one graph gets scored, but that score gets multiplied by 4? What if a team makes 3 great graphs but a mistake on the 4th one which is scored? Or vice versa? If it's just a time issue to get all graphs scored, why not require just one? Or let the students decide which of the 4 to score, not "selected by the event supervisor."

[windu34]

I didn't see anything in the rules prohibiting laser alignment (unlike scrambler, for instance), so I imagine it'll be a simple Pythagorean calculation, and I imagine the hope is that the graphs will actually be useful!

Speaking of graphs, rule 6.c.v seems a little weird - only one graph gets scored, but that score gets multiplied by 4? What if a team makes 3 great graphs but a mistake on the 4th one which is scored? Or vice versa? If it's just a time issue to get all graphs scored, why not require just one? Or let the students decide which of the 4 to score, not "selected by the event supervisor."

Usually all graphs are done in the same format by the team so if one graph has a mistake, they all will have the same mistake. The point of the graphs is that students are SUPPOSED to be graphing velocity by time, acceleration by time, etc. We are SUPPOSED to be using physics to calculate how to calibrate our device (of course most students don't)

As for the laser, my team has a distance laser that is accurate to the mm so I might just use that instead of relying on the ES to be precise on target placement (which most probably wont be able to)

[asthedeer]

Just received my copy of the rules yesterday.

Alright......so someone please tell me that the 0.1cm distances for Nationals is a misprint. Like seriously, how are event proctors going to measure that?

[chalker]

I didn't see anything in the rules prohibiting laser alignment (unlike scrambler, for instance), so I imagine it'll be a simple Pythagorean calculation, and I imagine the hope is that the graphs will actually be useful!

Speaking of graphs, rule 6.c.v seems a little weird - only one graph gets scored, but that score gets multiplied by 4? What if a team makes 3 great graphs but a mistake on the 4th one which is scored? Or vice versa? If it's just a time issue to get all graphs scored, why not require just one? Or let the students decide which of the 4 to score, not "selected by the event supervisor."

This isn't a new change this year. It's actually something we've done in several events for a while now. The bottom line is it IS a time issue, but we also want to encourage significant testing beforehand. This technique is the best compromise we can reach on that.

[chalker]

Just received my copy of the rules yesterday.

Alright......so someone please tell me that the 0.1cm distances for Nationals is a misprint. Like seriously, how are event proctors going to measure that?

Darnit... good catch. It should be 0.1m (or 10cm). Just goes to show that no matter how many sets of eyes we have on the rules, simple things like this slip through the cracks. I'll get a rules clarification posted ASAP.

[SPP SciO]

The point of the graphs is that students are SUPPOSED to be graphing velocity by time, acceleration by time, etc. We are SUPPOSED to be using physics to calculate how to calibrate our device (of course most students don't)

I disagree with this. I would think that a more useful graph leaves the raw physics out of it. For example, a machine that adjusts the height of the mass being dropped would do well to plot height in cm, or chain link number or peg slot etc on the X axis - whatever was most relevant to the device. It's a proxy for gravitational potential energy, but so many other factors are involved that I'm not sure it's ever worth the energy to go through all the calculations - from a competitive standpoint anyway. Educationally, it's a great idea!

[windu34]

The point of the graphs is that students are SUPPOSED to be graphing velocity by time, acceleration by time, etc. We are SUPPOSED to be using physics to calculate how to calibrate our device (of course most students don't)

I disagree with this. I would think that a more useful graph leaves the raw physics out of it. For example, a machine that adjusts the height of the mass being dropped would do well to plot height in cm, or chain link number or peg slot etc on the X axis - whatever was most relevant to the device. It's a proxy for gravitational potential energy, but so many other factors are involved that I'm not sure it's ever worth the energy to go through all the calculations - from a competitive standpoint anyway. Educationally, it's a great idea!

No I agrees with you, I'm just stating the point of the graphs from the rule writers prospective; we are supposed to be using actual physics, but its easier and more practical for most teams to just use the graphs for raw specs of our device