Consistent Mass Matrix

M = m \cdot [\begin{matrix} 1 & 0 & 0 & 0 & 0 & 0 \\ 0 & 1 & 0 & 0 & 0 & 0 \\ 0 & 0 & 1 & 0 & 0 & 0 \\ 0 & 0 & 0 & (Y^{2} + Z^{2}) & (- X \cdot Y) & (- X \cdot Z) \\ 0 & 0 & 0 & (- X \cdot Y) & (X^{2} + Z^{2}) & (- Y \cdot Z) \\ 0 & 0 & 0 & (- X \cdot Z) & (- Y \cdot Z) & (X^{2} + Y^{2}) \end{matrix}]

m	Mass
X, Y, Z	Distance to the center of the total mass

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