Experiments in a closed-cycle cryostat suffer from vibrations caused by its pulse tube. To reduce this disturbance, a vibration isolator needs to be placed inside the cryostat. Since mechanical dampers do not work in a cryogenic environment, it requires active damping. This thesis is about the design of a controller for such an active vibration isolator. To model the vibration isolator with a limited amount of sensors, sensor roving is applied. The PO-MOESP algorithm for data-driven subspace identification is extended to build a single black box model from the input-output data of a series of sensor roving experiments. A cautious Wiener filter is proposed to control the vibration isolator.