Method for unique collisions between 2 subdivided ellipses

AI Thread Summary
The discussion focuses on finding a method to determine the number of unique collisions between two subdivided ellipsoids, each subdivided into three zones per quarter and with rotation angles limited to 15°. The challenge arises from the infinite potential outcomes of collisions, prompting the need to simplify this to a manageable number, such as 32 unique collisions. The approach includes using symmetry to eliminate duplicate collision outcomes, considering both the order of collisions and their spatial orientation. The author is uncertain if a pre-existing method exists or if a Monte Carlo approach would be suitable for this problem. Suggestions for tackling this issue are welcomed as the author contemplates a manual solution.
Michel_vdg
Messages
107
Reaction score
1
Hello,

I would like find a way to figure out how many unique collision there are between 2 equally subdivided ellipsoids (velocity=1).

When you have 2 ellipsoids and you let them collide than you have an infinite amount of possible outcomes.

The goal is to reduce this infinite number to a manageable list of for example unique 32 collisions by:
  1. Subdividing the ellipsoids, so instead of having an infinite number of points on these ellipsoids where they can hit, they are subdivided into 3 zones (I-II-III per quarter).
  2. Reduce the possible rotation angles into steps of 15°
  3. Using symmetry, to cancel out the collisions that are the same when A hits B vs. B hits A, and the outcome of a collision on the left side is symmetric to one on the right, or back and front etc.
(Note, the use of 3 Zones and 15° Angles is arbitrary, i guess once a method is found these could be easily changed into whatever.)

--

Attached is an overview where the Ellipse A is Set and B comes flying in (see pic.), and where:
  • B is shifted a couple of steps along the vertical-axis (right-top).
  • B is rotated in relation to A in steps of 15° (left-bottom)
  • B is rotated in relation to A in steps of 15° and B itself is rotated 15° (right-bottom)
  • B is shifted a couple of steps along the horizontal-axis and B itself is rotated 105°(left-top).
--

I don't know if such a method already exists or if this is perhaps something that should be solved with a Monte Carlo method or ... all suggestions are welcome to tackle this issue.

Kind regards,

m.

getImageAttachment?filename=Collision_Ellipsoids.png
 
Mathematics news on Phys.org
... seems like I better figure this out 'manually' ...

getImageAttachment?filename=manually.png
 
Thread 'Video on imaginary numbers and some queries'
Hi, I was watching the following video. I found some points confusing. Could you please help me to understand the gaps? Thanks, in advance! Question 1: Around 4:22, the video says the following. So for those mathematicians, negative numbers didn't exist. You could subtract, that is find the difference between two positive quantities, but you couldn't have a negative answer or negative coefficients. Mathematicians were so averse to negative numbers that there was no single quadratic...
Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. In Dirac’s Principles of Quantum Mechanics published in 1930 he introduced a “convenient notation” he referred to as a “delta function” which he treated as a continuum analog to the discrete Kronecker delta. The Kronecker delta is simply the indexed components of the identity operator in matrix algebra Source: https://www.physicsforums.com/insights/what-exactly-is-diracs-delta-function/ by...
Thread 'Unit Circle Double Angle Derivations'
Here I made a terrible mistake of assuming this to be an equilateral triangle and set 2sinx=1 => x=pi/6. Although this did derive the double angle formulas it also led into a terrible mess trying to find all the combinations of sides. I must have been tired and just assumed 6x=180 and 2sinx=1. By that time, I was so mindset that I nearly scolded a person for even saying 90-x. I wonder if this is a case of biased observation that seeks to dis credit me like Jesus of Nazareth since in reality...
Back
Top