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me_myself_and_i »» models Re: Intriguing Items of Discovery   posted: 09-Jul-02 14:22   »»  and how did you make the sqaure?

guest: null Re: Intriguing Items of Discovery   posted: 09-Jul-02 15:27   »»  how do you do, _coolhand_, Coaldiamond, oooo, Lectvay, qwertilliopasd and other sodacreators. i think i figured out this phenomena, but i cannot explain it well, because my mother tongue is not english. indeed, i'm going to explain it, as possible as i can... step1: in sodaconstructor, value of spring force has relation with only extension of the spring<proportional maybe>, and does not have any relation with the length at rest. see this http://sodaplay.com/constructor/player.htm?&getmodel=mono2002+force_extension_relationship these are variety length of springs. left-side one is a zero-length spring, 2nd one is 1-pixel-length, 3rd is 2-pixel, and so on. besides, they are located as the free masses line up horizontally. try drag G value up slowly. then, you will see all of them are elongated similarly, and not related to their length at rest. step2: think about a rectangular with diagonal lines. as we see in step1, the pulling force of spring is related to its extension. now, let's assume that the force is proportional to extension. so, for exsample, if the ratio of two side lines = 2 : 3, the forces acting on the springs = 2 : 3 also. so, the direction of the resultant of these two vectors overlaps the diagonal line. the resultant of these two vectors and the expanding force acting on the diagonal line are completely on a straight line and the direction of the force is opposite. so, the length of these lines come to settle in a fixed value. this happens only the shape is rectangle and the side springs are zero-length. i cannot explain it better. i want to show you some figures somehow. mono(mono2002, nanopico)

qwertilliopasd »» models »» homepage Re: Intriguing Items of Discovery   posted: 09-Jul-02 19:13   »»  I beleive that our laws of physics cannot explain what is happening in my model because the model itself defies physics. A spring is created with a length of 0. A physics rule in Constructor states that all springs are stretched/compressed until all forces are equal. The one thing that makes this model anti-physics is: How do you stetch/compress something that doesn't exist (Zero is Nothing, Ziltch "Zip") The constructor is stretching something that isn't exactly there. (as stated ealier: "Zip-Spring" is my term for a spring with absolutely NO length at all...Impossable in the real world)

Lectvay »» models »» homepage Re: Intriguing Items of Discovery   posted: 09-Jul-02 19:33   »»  Wow - so great to see posts from _coolhand_ and mono. I am inspired by both of you. As usual, mono, I think your explaination is dead on. But I had some trouble understanding step2; I might come back and read it another time and see if I can understand it better. step1 certainly demonstrated an interesting point. Although it still hasn't "clicked" why this phenomenon occurs, I'm working on some cool ways to use it in models. I think it has potential. I would suggest, qwertilliopasd, that you submit your invention in its simplest form to the sodazoo. It's a cool discovery and should be recorded there. And you're certainly the one to have your name on it.

qwertilliopasd »» models »» homepage Re: Intriguing Items of Discovery   posted: 09-Jul-02 19:42   »»  I've transfered it to Qwerty and sent it.

Lectvay »» models »» homepage Re: Intriguing Items of Discovery   posted: 10-Jul-02 00:34   »»  This is copied from an e-mail I sent: ---- Open this one in construct mode to see how it's constructed. All the outer springs are zero-length, and diagonals are the length measured at the top. http://sodaplay.com/constructor/player?&getmodel=Lectvay+Test1 When simulated, the top figure stays stable and behaves as a double square/parallelogram. The other two collapse. I can't figure out how two extra zero-length springs are actually providing support... Here are some weird things I made: http://sodaplay.com/constructor/player?&getmodel=Lectvay+strange grab the point of the triange side, and sort of drag it outward and then up in a circular motion. If you do it right, the whole thing sort of reverses. I think you'll see what I mean. http://sodaplay.com/constructor/player?&getmodel=Lectvay+strange2 Kind of stretches in weird ways.

Supa_soaker »» models Re: Intriguing Items of Discovery   posted: 10-Jul-02 02:05   »»  if you play with it, it makes it a cool interaction toy, i made it be a box!

qwertilliopasd »» models »» homepage Re: Intriguing Items of Discovery   posted: 10-Jul-02 03:18   »»  You can get the oddest things... (I tried the same thing as the two that collapsed, but It didn't work like I wanted it, so I moved on...I'm glad you're persistant)

guest: Kevino Re: Intriguing Items of Discovery   posted: 10-Jul-02 06:07   »»  Hi! I accidentally made on of those things too. After Lectvay showed me how to make zero length springs, I just made a 'ring' of 4 dots connected by zero length springs, and then I made the diagonals the same length. Since there is no 'compression' force on the small springs on the perimeter, all of the force must be stretching them out. That makes the diagonals levers. Now picture a lever (like a floor jack) with the handle at a 45 degree angle from the floor. If you apply force straight down you get a certain leverage, but if the handle is almost horizontal, and you push straight down you actually get more force. Now picture the handle almost straight up, like 85 degrees, and you push straight down on the end directly towards the floor. You don't get much force to rotate that handle downwards. So, the zero length springs are stretched equally when the diagonals are at right angles to each other. When the angle changes, the shorter side springs are pulling with less force than the longer side springs, but it's easier for them to keep the rectangle in that shape, due to the easier leverage. Conversely, the springs on the longer sides of the rectangle are stretched further, and are pulling harder, but the angle of the leverage make it harder for them to pull the rectangle back into a square. Apparently these 'counteracting' forces are at an equilibrium, and the shape is 'at rest' regardless of the angles or the magnitude of the stretch of the zero-length springs. I am making no claims, but It seems to make sense to me! Another way of picturing it is.. stand a pencil straight up on it's eraser, and hold it by the eraser, and place a weight on the point. There is not a lot of force trying to rotate that pencil, but if you change the angle of the pencil, the pencil really wants to rotate, and the hardest angle to hold that weight up is when the pencil is almost horizontal. I just hope you can see how this applies to the diagonals in the rectangle! I'm finished spouting off at the mouth! Please forgive me. Hey, check this out... http://sodaplay.com/constructor/player.htm?&getmodel=Kevino+Pandoras_4th_Dimension

guest: Kevino Re: Intriguing Items of Discovery   posted: 10-Jul-02 06:34   »»  I forgot to mention that zero-length springs really are springs (or rubberbands) They begin at length 'zero' and can only be stretched. The force does increase the farther you stretch them. And they do not stop pulling until they reach length zero. (although the force is very small when they are almost at zero length) They behave like regular springs, except that they never reach a "length where they begin to push" They always pull. But their behaviour is very little different from a spring of length 1 or 3 pixels otherwise. You cannot 'program' them as muscles because a muscle is just an oscillation making the length of a spring shorter and longer. There is no shorter or longer than zero length. They do increase in 'pull force' the further you stretch them. I tested this by making a string of 3 points connected by 'zero' springs. Then I 'stretched' them with a specific length spring from point A to point C. The longer the 'stretcher', the bigger the space between the 3 dots. Hence regular spring behavior. The cool anomaly of the 'magic' rectangle must be explained by leverage. I think it's a neat discovery that the equations make an equilibrium, even if they weren't designed to do so.. See ya! Kevino

Lectvay »» models »» homepage Re: Intriguing Items of Discovery   posted: 10-Jul-02 07:18   »»  That does make quite a bit of sense to me. Thanks for the explaination.

me_myself_and_i »» models Re: Intriguing Items of Discovery   posted: 10-Jul-02 11:52   »»  this is also funny, it seems that if you make springs that have length zero length in construction mode, they stay that way. if you shake this pointa bit, it will become a triangle http://sodaplay.com/constructor/player.htm?&getmodel=me_myself_and_i+pointtriangle

me_myself_and_i »» models Re: Intriguing Items of Discovery   posted: 10-Jul-02 12:18   »»  and i don't really understand the movement of this model of me http://sodaplay.com/constructor/player.htm?&getmodel=me_myself_and_i+strangewalker

SirDougie »» models Re: Intriguing Items of Discovery   posted: 10-Jul-02 14:55   »»  im still not sure I understand what zero length springs are. Can you show me how to make them?

Lectvay »» models »» homepage Re: Intriguing Items of Discovery   posted: 10-Jul-02 18:19   »»  I gave an explaination of it here: http://sodarace.net/forum/thread.jsp?forum=17&thread=315 Basically, they are constructred by connected two masses when the two masses are directly on top of each other. Let me know if you still need help.

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