rt_trnorm - normalize a homogeneous transform[view code]

Calling Sequence

TN = rt_trnorm(T)

Parameters

• T : 4-by-4 matrix. The homogeneous transform which has to be normalized.
• TC : 4-by-4 matrix. The resulting normalized homogeneous transform.

Description

Return a normalized copy of the homogeneous transform T. Finite word length arithmetic can lead to homogeneous transformations in which the rotational submatrix is not orthogonal, that is, det(R) ~= 1.

Examples

   // The following example shows how rt_trnorm() can be used to normalize
   // a given homogeneous transform.

   // generate a homogeneous transform
   T = rt_roty(%pi/3),

   // perturb T
   T = [rt_tr2rot(T) + 1e-7*ones(3, 3), [0; 0; 0]; 0, 0, 0, 1],

   // compute determinant of its rotational submatrix
   det(rt_tr2rot(T)),

   // generate a normalized copy of T
   T2 = rt_trnorm(T),

   // compute determinant of its rotational submatrix
   det(rt_tr2rot(T2)),

  

See Also

rt_diff2tr,  

Authors

original Matlab version by

Peter I. Corke CSIRO Manufacturing Science and Technology

Scilab implementation by

Matteo Morelli Interdepartmental Research Center "E. Piaggio", University of Pisa

Bibliography

Corke, P.I. "A Robotics Toolbox for MATLAB", IEEE Robotics and Automation Magazine, Volume 3(1), March 1996, pp. 24-32

Funda, J. "Quaternions and homogeneous transform in robotics." Master's thesis, University of Pennsylvania, Apr. 1988.