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Old 11-15-2012, 02:22 PM   #41 (permalink)
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Originally Posted by agentSmith View Post
....If you fire 500 down a lane and hit a guy with 3, then you might have well as shot 497 down into a garbage can in the morning when it wouldn't keep you from hearing the action, then during the game just shoot the 3 that did all the work anyway....
Well, how do you know which 3 to keep? With my luck/skill, I would have shot the 3 that did all the work in the garbage can.
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Old 11-15-2012, 02:47 PM   #42 (permalink)
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The O.P. was a little vague in the request but, he did convey that he was looking for test data reflecting the effect of BPS on one's ability to pass through without being hit. Later, he stresses that he wants to see the math-related to the test.

As far as the Punkworks test goes, it's the most comprehensive test to date and, yes it has limitations. the premise of the test was whether or nor a certain BPS would be able to lock down a lane. What they got right in the test- a fixed marker, operating at known BPS rates, known distances, an assortment of runners, starting a lane at hip height, then having a runner run through it. Unfortunately, I can't find the data so I can't comment on findings and I can't find any discussions of the data. I suspect that the forum might have lost some posts because it's unusual that in the actual post-test thread, there's no significant discussion and, in the previously linked thread, the topic ends with the posting of the video. Without that information, I cannot say if they accounted for bounces in the data nor, can I comment on their findings. If I actually cared about laning performance, I would ask Bryce or Cockerpunk about it.

As far as the math goes, nobody has ever really posted any meaningful theories. A lot of folks attempt to theorize based on the size and velocity of the runner, the distance between shots, the velocity, and, in some cases, the average lateral and vertical spread of the rounds. Accounting for the trajectory factors seems to be fairly straightforward however, it's the target that is the bigger problem. It's not just a forward moving monolith but, a multi-jointed object with segments moving forward and rearward along the direction of travel.

For example, imagine that you are a paintball traveling down the lane in the perfect ballistic trajectory (meaning you're straight as an arrow and dropping due to gravity and drag). A runner is intersecting with your path from your right. What part of him will intersect your path first? One of his arms as they rotate forward and back? His body? Which part of him will be in the path when you reach him? Maybe you miss his left arm and hit his body, or maybe your flying at just the right speed to where you miss his left arm and body and instead, hit the inside of his right arm. Trying to model this on paper would be pretty much impossible for most (if not all) of us. And this is with the simplified ballistic flight.
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Originally Posted by Tom Kaye -in response to FS price critics
Unfortunately all of you have played the one "speedball" game of paintball for so long you can't conceive of other ways to do this and hence any new ideas seem stupid.
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Old 11-15-2012, 02:51 PM   #43 (permalink)
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Originally Posted by P0E View Post
As far as basic calculations and mathematical proofs being nothing but tools ... Look at the maximum number of shots from a 68/4500 calculation I post around the internet and Punkworks uses. It's wrong thanks to some pretty basic incorrect assumptions, but as far as anyone knows... it is an absolute certainty because it was proven with MATH.
i know nothing about what calculation you were talking about, but if it's a theoretical maximum, then real life loss of energy will always be greater and so it wouldn't necessarily invalidate your math if that was the only problem.

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Originally Posted by uv_halo View Post
As far as the math goes, nobody has ever really posted any meaningful theories. A lot of folks attempt to theorize based on the size and velocity of the runner, the distance between shots, the velocity, and, in some cases, the average lateral and vertical spread of the rounds. Accounting for the trajectory factors seems to be fairly straightforward however, it's the target that is the bigger problem. It's not just a forward moving monolith but, a multi-jointed object with segments moving forward and rearward along the direction of travel.
that also has to do with at which point does the tester want to deem those differences negligible. if the movement of the paintballer is oversimplified, then you might overestimate the required bps; on the other hand if you account for the joints and movements of the paintballer then your test result would only apply to when the paintballer runs in that exact way and posture. practically i think the former is better.

Last edited by heinous; 11-15-2012 at 02:55 PM.
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Old 11-15-2012, 03:01 PM   #44 (permalink)
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Quote:
Originally Posted by uv_halo View Post
The O.P. was a little vague in the request but, he did convey that he was looking for test data reflecting the effect of BPS on one's ability to pass through without being hit. Later, he stresses that he wants to see the math-related to the test.

As far as the Punkworks test goes, it's the most comprehensive test to date and, yes it has limitations. the premise of the test was whether or nor a certain BPS would be able to lock down a lane. What they got right in the test- a fixed marker, operating at known BPS rates, known distances, an assortment of runners, starting a lane at hip height, then having a runner run through it. Unfortunately, I can't find the data so I can't comment on findings and I can't find any discussions of the data. I suspect that the forum might have lost some posts because it's unusual that in the actual post-test thread, there's no significant discussion and, in the previously linked thread, the topic ends with the posting of the video. Without that information, I cannot say if they accounted for bounces in the data nor, can I comment on their findings. If I actually cared about laning performance, I would ask Bryce or Cockerpunk about it.

As far as the math goes, nobody has ever really posted any meaningful theories. A lot of folks attempt to theorize based on the size and velocity of the runner, the distance between shots, the velocity, and, in some cases, the average lateral and vertical spread of the rounds. Accounting for the trajectory factors seems to be fairly straightforward however, it's the target that is the bigger problem. It's not just a forward moving monolith but, a multi-jointed object with segments moving forward and rearward along the direction of travel.

For example, imagine that you are a paintball traveling down the lane in the perfect ballistic trajectory (meaning you're straight as an arrow and dropping due to gravity and drag). A runner is intersecting with your path from your right. What part of him will intersect your path first? One of his arms as they rotate forward and back? His body? Which part of him will be in the path when you reach him? Maybe you miss his left arm and hit his body, or maybe your flying at just the right speed to where you miss his left arm and body and instead, hit the inside of his right arm. Trying to model this on paper would be pretty much impossible for most (if not all) of us. And this is with the simplified ballistic flight.
To do this, you would have to combine the physics of it with the statistics. Measuring the average spread of paintballs has been done several times in accuracy tests. Using that and the known BPS you are using, you could determine the window of time and distance the player has to get through from ball to ball. You could set up photo gates and have a runner go through several times to account for the moving extremities triggering early and late in the process. This is still just testing if a runner can fit in the window though. No matter who is doing the running, if they cross the lane at the end of the window they will lose.

Because of that one aspect (timing of the player running into the lane) I don't really care if anyone does the math or not. It has been shown that you can fit through a lane, it just depends on the timing, which is something that the runner can't control, so it's a matter that is out of their hand and essentially boils down to luck.
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Old 11-15-2012, 03:26 PM   #45 (permalink)
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Quote:
Originally Posted by heinous View Post
that also has to do with at which point does the tester want to deem those differences negligible. if the movement of the paintballer is oversimplified, then you might overestimate the required bps; on the other hand if you account for the joints and movements of the paintballer then your test result would only apply to when the paintballer runs in that exact way and posture. practically i think the former is better.
Wait, I'm talking about the 'theoretical math'- Testing is done as punkworks did with whatever modifications to the test as one sees fit. For example, a larger sample size of runners of similar speed and build to account for different joint positions while crossing the lane. Or, the same individuals but running the same BPS lane from different starting distances (so that they're joints are more likely to be in a different position from attempt to attempt).
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Quote:
Originally Posted by Tom Kaye -in response to FS price critics
Unfortunately all of you have played the one "speedball" game of paintball for so long you can't conceive of other ways to do this and hence any new ideas seem stupid.
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Old 11-15-2012, 03:39 PM   #46 (permalink)
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Originally Posted by desertT1 View Post
To do this, you would have to combine the physics of it with the statistics. Measuring the average spread of paintballs has been done several times in accuracy tests. Using that and the known BPS you are using, you could determine the window of time and distance the player has to get through from ball to ball. You could set up photo gates and have a runner go through several times to account for the moving extremities triggering early and late in the process. This is still just testing if a runner can fit in the window though. No matter who is doing the running, if they cross the lane at the end of the window they will lose.

Because of that one aspect (timing of the player running into the lane) I don't really care if anyone does the math or not. It has been shown that you can fit through a lane, it just depends on the timing, which is something that the runner can't control, so it's a matter that is out of their hand and essentially boils down to luck.
I agree, and argue it's too complex for most folks here to do it thoroughly if not from a competency standpoint, then a logistical standpoint. Therefore, it'll likely never be done. The broader point being that it's worthless to look for the 'math'.

I agree that in the end, the math doesn't matter. The only thing that the current testing could show (I can't see the data to confirm) is whether or not a given BPS (Between 8 and 15) could render a lane uncrossable.
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Quote:
Originally Posted by Tom Kaye -in response to FS price critics
Unfortunately all of you have played the one "speedball" game of paintball for so long you can't conceive of other ways to do this and hence any new ideas seem stupid.
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Old 11-15-2012, 04:56 PM   #47 (permalink)
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Quote:
Originally Posted by uv_halo View Post
... Unfortunately, I can't find the data so I can't comment on findings and I can't find any discussions of the data. I suspect that the forum might have lost some posts because it's unusual that in the actual post-test thread, there's no significant discussion and, in the previously linked thread, the topic ends with the posting of the video.
...

As far as the math goes, nobody has ever really posted any meaningful theories.
....
Did you check the experiment vault?

If I recall correctly the thread was locked because Cockerpunk was getting butt hurt. Wouldn't surprise me if he edited or deleted it.

Is he still stating spin effects on walking vortecies is the main cause of inaccuracies with no data to back that up? Shame they never measured accuracy while recording that HSV footage of spinning balls.


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Originally Posted by heinous View Post
i know nothing about what calculation you were talking about, but if it's a theoretical maximum, then real life loss of energy will always be greater and so it wouldn't necessarily invalidate your math if that was the only problem.
The calculation ignores efficiency of the marker by simply comparing total energy in the tank to total energy expelled. This is noted up-front so it's not an issue. The incorrect assumption is in regards to the formula PV=E and the circumstances where it holds true.

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Originally Posted by heinous View Post
that also has to do with at which point does the tester want to deem those differences negligible.
This is a similar issue with their accuracy test. Measuring accuracy is IMPOSSIBLE without knowing the shape and size of your target. Since you can't measure these factors for every scenario, you can't measure the accuracy of a marker for every scenario.

Punkworks instead attempts the next best thing, assume all targets are circular and the pattern is always evenly distributed. That allows them to measure the probability of hitting an object... so long as the target is large enough to encompass the entire circular area created by a high probability vector. Big assumption in my opinion.

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Originally Posted by Slipknot666 View Post
someone calculated the the myth that 15 bps is better then 12 bps, and did the times that no matter if it's 12 bps or 15 bps the time that it took to run through the paint you'd still get hit.
As hard as that is to read, I think the OP is asking if 15pbs is better than 12bps. A second question appears to be if either rate could be impenetrable.

The Punkworks tests were useful in that they show under certain circumstances you could get through a 15bps lane. Might require a 100' range, might only happen on sunny days, might only happen with those finely tuned athletes, but it happened.

Does any sane person question whether 15bps gives you a higher probability of hitting someone crossing a lane?
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Old 11-15-2012, 10:05 PM   #48 (permalink)
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It seems that they (TechPB) are still restoring the database and, I've seen a bit more of the discussion (and more importantly the data) but, there's only three pages worth.
Here's my current thoughts: compare only the data for each individual due to size, speed and arm movement differences between individuals. Unfortunately, Bryce has the largest sample of runs but, not enough at each BPS to get a good statistical sample. They would probably admit as much. But, throughout the data, they prove that it's possible, even at 15BPS to run through an established, non-tracking lane. But, there's not enough data to support probability claims.

As far as accuracy goes, Vortex shedding has been shown to jack up the trajectory of a perfectly smooth sphere- see any number of aerodynamics studies. A paintball with it's randomly oriented seam, and slightly ellipsoidal shape (again in random orientations) will certainly not do any better, especially with random spin (in magnitude and orientation). I believe that Cockerpunk would agree with me on this. In any case, I don't believe they are done with 'accuracy' testing. If the forum date info is correct, they did another bore fit test in late September, and that thread ends with several folks and them considering further testing to nail down some theories.

In regards to their accuracy statements- to be clear, their vector and Standard deviation values reflect projectile spread and not probability of impact which, could be influenced by the size of the target, how effective are the aiming method and devices are, the player's abilities, etc. The use of a vector is due to the fact that there has been negligable elliptical bias seen in the data that appeared across any single test session. I can't be bothered to crunch the data now but, I suspect that if one were to examine this data they wouldn't even be able to correlate shot velocities with impact deviation in the Y-axis.

I believe that you can apply the vector to determine your probability of hitting someone with a single shot. For example, consider the CP .685 14" barrel data. Let's say you sight in on those 20 rounds so that the center of the group is centered on your reticle. In this case, it would you would sight in at the -3.14,-4.36 (x,y) position on the board. While keeping the barrel locked in, you fire another set of shots. Assuming that 20shots is enough of a sample size, 68% of your following shots should land within a radius of 14.53" If you double the radius, it should contain 95% of the shots. Therefore, if you wanted to be 95% sure of hitting your target with a single shot, don't aim at anything smaller than 58.12" tall/wide when 100' away.
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Quote:
Originally Posted by Tom Kaye -in response to FS price critics
Unfortunately all of you have played the one "speedball" game of paintball for so long you can't conceive of other ways to do this and hence any new ideas seem stupid.
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Old 11-16-2012, 06:08 PM   #49 (permalink)
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With any physics problem, always simplify it to a reasonable extent to explain it at first. Then make it more complicated by adding real-world effects. Explaining a physics problem with major simplifications is still a valid way of analysing it. The differences between ideal and real-world is often very small, and it would be in this case as the time interval we are analysing is very small.

Note: This example only illustrates the possibility of clearing a line of fire. It does not address the probability of successfully clearing the line of fire.


So......

Put some numbers for 0.68 cal, 3 g paintballs into Chairgun Pro. I put in a ballistic coefficient of 0.005, a very big assumption, as I don't know the BC of a paintball, but it is assumed to be quite crappy, so I picked the lowest limit available in this program.

Assume paintballs are travelling parallel to the ground in the short time period of this example. Also disregard deceleration during this time period. In reality paintballs are arcing and constantly decelerating once in the air.

Situation: You are trying to cross a lane 30 feet from your opponent shooting 15 bps.
Initial velocity = 280 ft/sec
Paintball velocity @ 30 feet = 218 ft/sec (from ChairGun Pro)
15 bps = 1/15 = 0.0667 sec time interval between paintballs

The first question to ask is will a person fit between two paintballs in this setup.

Distance travelled in 0.0667 sec by a 218 ft/sec paintball before next paintball is shot:
d = [v(initial) + v(final)] / 2 x t assume no deceleration in this time period
d = v x t
= 218 x 0.0667 = 14.5 feet

Therefore, there is a gap of about 14.5 feet between paintballs. All humans will therefore fit between the gap (I measure about 2 feet left to right).

Next question: how fast does a person have to run in order to clear the gap?

I measure about 1 foot wide front to back. So how fast do I have to run, to clear 1 foot in 0.0667 sec?

d = v x t
v = d / t
= 1 / 0.0667 = 15 ft/sec
= 10.2 mph

I have to be already running at that speed when I cross the line of fire, and of course time it so the first ball just misses the front of my big fat tummy, and the second ball misses the back of my big fat butt. Also, we are not taking into account flailing arms. It's as though I ran with my arms by my sides.

Now if you're fatter and measure 1.5 feet wide, you'd have to run 15.3 mph, so it definitely pays to lay off those Twinkies!!!!!

To put this into perspective, average walking speed is 3-4 mph. Usain Bolt is touted to top at around 27 or 28 mph.

At 20 bps, t = 1/20 = 0.05 sec. The gap is only 10.9 feet. In the above situation, I would have to run 13.6 mph and have better timing. The fat person has to run 20.4 mph!!!

Note that the further the stream of balls travel, the shorter the gap becomes between paintballs. Why? Because if we put back in deceleration effects, the ball behind is travelling ever so slightly faster than the ball directly in front, at any point in the flight path. So the back ball shortens the gap over time. However, the frequency of balls shot doesn't change, so the time I have to run is the same. Also, the velocity of the paintballs are a lot slower. It would actually be quite difficult to try to cross a hail of paintballs shot from 200 feet away, even though they might be only travelling 50 ft/sec at that distance.
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Old 11-16-2012, 08:04 PM   #50 (permalink)
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Quote:
Originally Posted by uv_halo View Post
As far as accuracy goes, Vortex shedding has been shown to jack up the trajectory of a perfectly smooth sphere- see any number of aerodynamics studies. A paintball with it's randomly oriented seam, and slightly ellipsoidal shape (again in random orientations) will certainly not do any better, especially with random spin (in magnitude and orientation).
...

In regards to their accuracy statements- to be clear, their vector and Standard deviation values reflect projectile spread and not probability of impact..
I'm well aware of all accuracy data collected by Punkworks and most other places on the interwebs. I was contributing before the forum went public.

Their accuracy statements reflect probability of impacting a circular object and have nothing to do with evenness of the spread. The probability is held constant by adjusting the circular target size to fit a fixed SD/CI. The assumption is that we are shooting at a target which is comparatively large. As the target size decreases, the probability depends more and more on the spread being 'even'**.

Imagine shooting at a 1" x 12" gap in bunker wall with two markers that have a 6" vector at that range. A marker with an uneven spread (high concentration near the center but with a larger overall diameter) would be more accurate in this scenario. i.e. More probable to hit the target. Also, if the pattern was more oblong. Attempts to discuss evenness of spread and shape were brought up several times.

** An 'even' spread for their purposes does not mean equidistant impact spots. It actually means there is a linear relationship between individual ball vector and number of shots. This would be a pattern that is very dense at the center and get less dense by the square. Not seen in paintball.

Quote:
Originally Posted by uv_halo View Post
I can't be bothered to crunch the data now but, I suspect that if one were to examine this data they wouldn't even be able to correlate shot velocities with impact deviation in the Y-axis.
I was the first to highlight that after Punkwork's first accuracy tests. There appeared, at that time and since, to be no correlation which I still feel is very important. Your graph resolutions are a little too low, but it would be nice to compare the expected drop delta to the results. I think this was brought up when I sent you a PM about your graphs being on a log scale.
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