## 40 Reputation

15 years, 340 days

## eq_1...

Hi Markiyan,

I'm still trying to understand the implications of your solution. Does this mean that the system is solvable? I'm afraid it's got pretty late where I am so I can't work through your latest post right now, time to get some sleep...

## eq_1...

Hi Markiyan,

I'm still trying to understand the implications of your solution. Does this mean that the system is solvable? I'm afraid it's got pretty late where I am so I can't work through your latest post right now, time to get some sleep...

## Numerical Solution...

Hi Markiyan,

Thanks for your continued help.Previously I just created a fairly low resolution plot and saw that there was a convergence in approximately the right area. I just tried to generate a numerical solution by setting up a search function with a resolution of 4d.p.

For the following parameters:

L21 = 302.7397; L3 = 245.4678;

I get q3=-3.577 and q4 = 32.2953

Interestingly this gives an (norm) error between desired and actual W of 0.0017. Though this sort of error would be perfectly acceptable in my application I can see why this non-zero solution would cause the solution to be unsolvable. Quite enlightening.

Someone also suggested that Maple may not be providing a solution as I have not constrained q3 and q4 to be between -360 to +360 degrees. I've tried to do this (using solve() assuming q3<2pi etc.) but I still get the same answer as before.

Thanks,

W = [Wx,Wy,Wz] = [-34.0053 37.9050 -524.3520]

q1 = -0.1870;q2 = 0.0584;

## Numerical Solution...

Hi Markiyan,

Thanks for your continued help.Previously I just created a fairly low resolution plot and saw that there was a convergence in approximately the right area. I just tried to generate a numerical solution by setting up a search function with a resolution of 4d.p.

For the following parameters:

L21 = 302.7397; L3 = 245.4678;

I get q3=-3.577 and q4 = 32.2953

Interestingly this gives an (norm) error between desired and actual W of 0.0017. Though this sort of error would be perfectly acceptable in my application I can see why this non-zero solution would cause the solution to be unsolvable. Quite enlightening.

Someone also suggested that Maple may not be providing a solution as I have not constrained q3 and q4 to be between -360 to +360 degrees. I've tried to do this (using solve() assuming q3<2pi etc.) but I still get the same answer as before.

Thanks,

W = [Wx,Wy,Wz] = [-34.0053 37.9050 -524.3520]

q1 = -0.1870;q2 = 0.0584;

## RootsOfs...

Thanks for the explanation John. I used tried map(allvalues,sol) to look at the roots and the answer wasn't pretty!

## RootsOfs...

Thanks for the explanation John. I used tried map(allvalues,sol) to look at the roots and the answer wasn't pretty!

## Reformulated system...

Hi hirnyk,

Thanks for trying to solve this. I think I understand what you have done, what does '**' mean in eq_2?

Forgive me if I've misunderstood your method but I am only trying to solve for q3 and q4. So {s1,c1,s2,c2} are already known and the system will be 8 equations with 4 unknowns. Or have I missed something? I will try this in a moment and see what happens.

By saying the system does not have a solution do you mean an algebraic solution? I did a quick numerical search of the equations (varying only q3 and q4) and the results always converge to a single point. So a unique numeric solution exists.

## Reformulated system...

Hi hirnyk,

Thanks for trying to solve this. I think I understand what you have done, what does '**' mean in eq_2?

Forgive me if I've misunderstood your method but I am only trying to solve for q3 and q4. So {s1,c1,s2,c2} are already known and the system will be 8 equations with 4 unknowns. Or have I missed something? I will try this in a moment and see what happens.

By saying the system does not have a solution do you mean an algebraic solution? I did a quick numerical search of the equations (varying only q3 and q4) and the results always converge to a single point. So a unique numeric solution exists.