SolveDesignProblem solves the three-points synthesis problem. The function returns a linkage where the target frame, which is attached to the coupler link passes through the three design frames.
The three-points synthesis problem has infinity solutions, the one returned by the function determined by the actual substitution values of the simple parameters. If the simple parameters are changed a different solution might be found.
The solver calculates the endpoints of the design postures of the coupler link from the design frames. The four simple parameters that is used to define these postures are displayed in the figure below:
Length of the coupler link
X coordinate of the design frame w.r.t LLRF of coupler link
Y coordinate of the design frame w.r.t LLRF of coupler link
Angle of the design fram w.r.t LLRF of coupler link