Instructions for Fiber Path Visualization

Panel Geometry

The domain is assumed to be a rectangular plate, with a given distance between fiber paths that represents the width of the tow placement head. The minimum radius of curvature can also be stipulated to determine the manufacturability of the ply. The units on these quantities are arbitrary.

Length (X) - Dimension of rectangular plate in horizontal direction (must be > 0)

Height (Y) - Dimension of rectangular plate in vertical direction (must be > 0)

Width of tow placement head - Distance between successive fiber paths. Must be large enough so that individual lines are distinct (error message will appear if too small)

Fiber Steering Definition

This method is used to stipulate a linear variation of the fiber orientation angle in a specific direction. The fiber paths are defined by four variables. First, the direction of the variation is given by Phi, which stipulates the angle between the X-axis and the r-axis. The origin for these axes is located at the center of the panel. Along the r-axis, the fiber orientation angle of the reference path varies linearly, with T0 being the angle at the origin and T1 being the value at r = d. This linear variation is repeated indefinitely so that the actual variation of the fiber orientation angle resembles a saw-tooth pattern in the r-direction.

Phi (degrees) - Angle between X-axis and direction of fiber angle variation (r-axis).

T0 (degrees) - Fiber orientation angle at r = 0 with respect to r-axis. (-90 < T0 < 90)

T1 (degrees) - Fiber orientation angle at r = d with respect to r-axis. (-90 < T1 < 90)

Note that the value of T1 is defined at the point on the reference path with r = d.

d - Characteristic distance (along r-axis) between fiber orientation angle definitions.

Represents half of the period of the saw-tooth function for the fiber orientation angle variation. Must be greater than zero and conform to the units of the panel geometry. Note that the value of T1 is valid only at the point on the reference path. In general, d = minimum(Xdim, Ydim)/2.

Allowable radius of curvature - Minimum turning radius allowed due to Manufacturing constraint (must be > 0)

Fiber Path Information

The output window draws the resulting fiber paths after Draw Fiber Paths has been selected. Also included is an estimate of the minimum radius of curvature for a ply with curvilinear tow paths. Portions of paths that fall below the allowable radius of curvature constraint are drawn in gray. If the input parameters produce an infeasible design (one with a zero radius of curvature) an error message is output along with the paths that are feasible.

Specific information can also be calculated at a given (x, y) point. This is performed by either clicking with the mouse at the desired point, or entering the (x, y) values within the Input Point windows and selecting the Calculate button. Output to the screen consists of the fiber orientation angle q and radius of curvature r at that given point.