Creating control surfaces

The APM Preprocessor has the ability to create control surfaces by deforming the mesh. To create a control surface add the following lines to the end of the .conf file.

[control_surface]
    x1 = 0.0000
    y1 = 0.0000
    z1 = 0.0000
    x2 = 0.0000
    y2 = 0.0000
    z2 = 0.0000
    x3 = 0.0000
    y3 = 0.0000
    z3 = 0.0000
    deflection = 0.0000
    differential_deflection = 0
    mirror = 1

The three vectors with components x1, y1, z1,x2,y2,z2,x3,y3,z3 define the mid-plane of the control surface. The hinge line is defined as x2-x1, y2-y1, z2-z1. The image below shows the three vectors and the resulting control surface mid-plane.

Definition of a control surface

Control surfaces should always be created on the left side of the $x-z$symmetry plane (negative $y$-direction). The APM Preprocessor will automatically mirror the control surfaces across the $x-z$symmetry plane.

Deflection specifies the amount of control surface deflection in degrees and differential specifies whether mirrored control surfaces deflect in the opposite direction.