In computer-assisted surgery, a computer display provides 3D guidance of tools during surgery. However, current guidance displays have a number of drawbacks. This thesis considers the advantages of a prototype guidance system for drilling tasks. We attached a small LCD screen and video camera to a surgical drill. The screen's point of view was controlled by moving the drill. A user study showed that the tool-mounted LCD screen can provide significantly better positional and angular accuracy than the conventional display. The study also showed that a video camera might not be useful for guidance. / Thesis (Master, Computing) -- Queen's University, 2007-09-18 00:31:10.965