Creating the common tangent plane to two surfaces

1 Load file "TangentPlane_SrfSrf.e3"



and start the Tangent Plane command.
 
2 Select the First Point on the surface on the right:



You can easily redefine the position of both selected points by using the corresponding handles or by typing the curve parameter value into the First UV and Second UV boxes respectively. Therefore, you are enabled to interactively check the existence of a common tangent plane. While you change the point position, as soon as a common tangent plane is detected, the warning will disappear and a preview of the plane will be displayed. The First surface vector drop-down list under More Options enables you to choose Tangent U or Tangent V as the first surface vector to be used when displaying the tangent plane. Similarly, the Second surface vector drop-down list enables you to do the same for the second point.
 
3 Select the second point on the surface on the left.



As you can see, a message warns you no tangent plane could be found.
 
4 To make the message disappear and obtain a tangent plane, deselect the Exactly on first point check box under More Options



Exactly on first point
When the Exactly on first point check box is selected, the program tries to create a tangent plane which is exactly through the first point you specified. If such a plane does not exist, a message is displayed warning you that no such plane is defined.
If you deselect the Exactly on first point, the program will calculate the point which is the closest to the one you specified and for which a tangent plane exists and will create this plane.
This is a solution in most situations.
 

5 Select or to confirm your selections and create the plane.
Use Cases