According to various embodiments, there is provided a control arrangement for maintenance of a collection of physical devices, the control arrangement including: a receiver configured to receive observation data, the observation data representative of physical conditions of each physical device of the collection of physical devices; a processor configured to compute respective maintenance output data of maintaining different combinations of the physical devices, based on the observation data; and a controller configured to determine the combination of the physical devices to be maintained based on a comparison of the computed respective maintenance output data, the controller further configured to control maintenance of the determined combination of the physical devices.