  In this paper, an analysis of the sensing volume coverage of robot workspace
as well as the shared human-robot collaborative workspace for various
configurations of on-robot Time-of-Flight (ToF) sensor array rings is
presented. A methodology for volumetry using octrees to quantify the
detection/sensing volume of the sensors is proposed. The change in sensing
volume coverage by increasing the number of sensors per ToF sensor array ring
and also increasing the number of rings mounted on robot link is also studied.
Considerations of maximum ideal volume around the robot workspace that a given
ToF sensor array ring placement and orientation setup should cover for safe
human robot interaction are presented. The sensing volume coverage measurements
in this maximum ideal volume are tabulated and observations on various ToF
configurations and their coverage for close and far zones of the robot are
determined.
