  This letter presents a self-contained system for robust deployment of
autonomous aerial vehicles in environments without access to global navigation
systems and with limited lighting conditions. The proposed system,
application-tailored for documentation in dark areas of large historical
monuments, uses a unique and reliable aerial platform with a multi-modal
lightweight sensory setup to acquire data in human-restricted areas with
adverse lighting conditions, especially in areas that are high above the
ground. The introduced localization method relies on an easy-to-obtain 3-D
point cloud of a historical building, while it copes with a lack of visible
light by fusing active laser-based sensors. The approach does not rely on any
external localization, or on a preset motion-capture system. This enables fast
deployment in the interiors of investigated structures while being
computationally undemanding enough to process data online, onboard an MAV
equipped with ordinary processing resources.
  The reliability of the system is analyzed, is quantitatively evaluated on a
set of aerial trajectories performed inside a real-world church, and is
deployed onto the aerial platform in the position control feedback loop to
demonstrate the reliability of the system in the safety-critical application of
historical monuments documentation.
