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C. Simplification of Motion Equations with Linear Constraints

 

Applying (10), the D-NURBS motion equations with linear constraints are

  equation871

To simplify (42) we first show that it reduces to the following

  equation891

As in Appendix B, tex2html_wrap_inline2499 . Hence, (43) is also expressed as

  equation907

Similar to (38), the two sides of (44) are integrals of two vectors, respectively. Hence, (44) holds if corresponding components of the two vectors are equal; i.e., for tex2html_wrap_inline2125 ,

  equation921

We now prove (45). Denoting the right side as R, we further expand it using the product rule of differentiation

displaymath2519

Furthermore, according to the property of the Jacobian matrix and the irrelevance of the order of differentiation, we have

displaymath2520

Combining the above two equations, we have

displaymath2521

Since R is a scalar, (45) follows.

The proof of

  equation955

parallels that in Appendix B, with tex2html_wrap_inline2103 replacing tex2html_wrap_inline2535 and tex2html_wrap_inline2537 replacing tex2html_wrap_inline2025 .



Demetri Terzopoulos | Source Reference