This function can be used to determine the vertical location of any marker in road reference frame. The function is useful on 3D roads to determine the height of points of interest with respect to road frame. The function determines the normal to the road surface by creating a plane by connecting the first 3 tire contact point locations. If there are four contact point location, 2 triangular planes are created and the normal is the average of normals of the 2 planes. The vertical location of the marker is the dot product of the road normal and the displacement of imrk with respect to rmrk. User needs to make sure that the reference marker (rmrk) used by the function is same as that used in the tire GFORCE statement.
The syntax to access this function is as follows:
VARIABLE/id, FUN=USER (1109,imrk, rmrk)
where:
id | = | Variable statement id |
imrk | = | Marker id whose displacement is requested |
rmrk | = | (Optional) Reference marker representing the road frame (default = 3) |