5.3.1 Basic Concepts

As in Section 3.1.1, collision detection may be viewed as a logical predicate. In the current setting it appears as $\phi : {\cal C}\rightarrow \{$TRUE$,\;$FALSE$\}$, in which the domain is ${\cal C}$ instead of ${\cal W}$. If $q \in {\cal C}_{obs}$, then $\phi (q) =$   TRUE; otherwise, $\phi (q) =$   FALSE.