Pattern-based vision for microrobotic manipulators calibration and servoing

International audienceThis paper presents recent results obtained with a visual method allowing absolute position measurements at nanoscale. Based on the direct phase analysis of pseudo-periodic patterns, this approach enabled fast measurements of position with large range-to-resolution ratios. Applications include microrobotic manipulators calibration and visual servoing but also microforce measurement by using a compliant structure. Rangeto-resolution ratio of 105 are typically overcome. For instance, the experiments have demonstrated a sub-nanometric resolution over a range of 168 µm, as well as a resolution below 50 nN for a 50 mN range for force measuremen