Position Measurement and Uncertainty Analysis for the Shutter Mechanism Mounted on the Rosetta Mission

An indirect measurement procedure is applied to the shutter mechanism mounted on the Wide Angle Camera and Narrow Angle Camera of the ESA Rosetta mission. The available direct measurements, such as the electrical current supplied to the actuation motors and the rotation of the motor shafts, are employed together with the kinematical and dynamical models of the mechanism to improve the position measurement of the shutter blade. An uncertainty analysis using the Kline-McClintock propagation formula and a Monte Carlo simulation is carried out, allowing to verify the compatibility of the obtained results.