Tracking results from hardware validation experiments for 9 different configurations (results referred to as trial 1–9, row-wise from top-left to bottom-right, in the text). Pairs of images show the left and right camera views from the da Vinci® system’s stereo endoscopes, overlaid with the best particles from the tracking algorithm rendered in cyan. In the experiments, only one surgical tool is being tracked, while manually controlled additional tools are placed in the view make the scene visually more complex.