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4.1 Planes with a fixed orientation relationship

A plane surface can be represented by this following equation:

where is unit normal vector to the plane and d is the distance to the origin. For each plane surface we consider a local frame centered on a point belonging to the plane (in practice this point is taken as the center of gravity of the measurement points), so the plane equation can be written as

Let's consider N planes, where the angles between planes' normals are known. The orientation relationship between the different planes are defined by the following constraints:

 

Each plane normal has also to satisfy the unity constraint

 

The constraint functions are squared in order to have convex functions. The constraints ( 15 ) and ( 16 ) can be written under a matrix formulation:

   

where , and are block matrices defined by:

and is the identity matrix.



Naoufel Werghi
Thu Jul 10 17:36:04 BST 1997