Minelab 8000

[Aziz]

Hi all,

now added multi path definition feature. A coil can consist of several individual parts.
Move, scale and rotate on section is also implemented.

Dilatation and contraction of wire path referred to its reference is also important.
I have maybe implemented 50 % of the required features.

[Aziz]

Dilatation and contraction is very important as a coil bundle can't be really realised with scale only commands.
And I am also thinking of cubic spline interpolation feature for coils. A better coil geometry and accuracy can be realised.

Oh man!, it is more than 34 years ago I have done cubic spline interpolations (in the exam!).
This might be a good job for AI coding...

[Aziz]

Yep, I really need 3d-cubic spline interpolation. This is a must-have feature.
We can model complex fusion reactor coil arrangements with it..

There we have the next evolution and slight changes:
I have to distinguish between a wire path (physically existing wires, implemented in the current version) and a geometric path (which does not create any wires). From the geometric path definition, I can create the smooth wire path finally.

Let me think of it further.
Thinking. Changing. Implementing. Testing.

[Aziz]

WTF, how to contract and dilatate a path?

I have finally found the implementation of the dilatation and contraction algorithm part (already implemented in 2024).
This is beeing used for magnetic flux calculation of the single wire element.
dir = 0: calculate magnetic flux up to the center axis of wire element
dir = 1: up to the outside of the wire element (dilatation)
dir =-1: up to the inside the wire element (contraction)
pLeiter->LeiterR is the dilatation/contraction distance (wire radius in this case).

I think, I can reuse the code section.

      // 2024 neu: Winkelabhängigkeit wird berücksichtigt
      //
      VEKTOR _dse, _R1e, _R2e;
      double a1, a2, tan2a1, tan2a2, rx1, rx2;

      VekCopy(_dse, pLeiter->ds);
      EinheitsVektor(_dse);

      VekCopy(_R1e, _R1);
      EinheitsVektor(_R1e);

      VekCopy(_R2e, _R2);
      EinheitsVektor(_R2e);

      a1 = _PI_H - acos(-SkalarProdukt(_R1e, _dse));
      a2 = _PI_H - acos( SkalarProdukt(_R2e, _dse));
      tan2a1 = tan(a1);
      tan2a1 *= tan2a1;

      tan2a2 = tan(a2);
      tan2a2 *= tan2a2;

      rx1 = pLeiter->LeiterR * sqrt(1.0 + tan2a1);
      rx2 = pLeiter->LeiterR * sqrt(1.0 + tan2a2);

      VekAddSkalarMul(_R1, _R1, rx1*dir, _R1e);
      VekAddSkalarMul(_R2, _R2, rx2*dir, _R2e);
​

Don't ask me what I have did. I don't know anymore.
But it speeds up the implementation.

AI totally sucks! It can't do it.

[Aziz]

Well ok,

dilatation/contraction of a path needs a more accurate solution.

This elliptical coil is done with duplicate scale modifier. Note, that the bundle thickness scales too.

And this is done with dilatate/contract modifier. The bundle thickness stays same.

But the latter one produces inaccurate wire locations.
Back to the black board.
AI, why don't you do that?