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This paper explores the possibilities of alignment methodologies using software tools, regardless of the industry they are intended for. We present a comparison of several methods for the alignment of temporal 3D elevation maps using commercially available software as compensation for the GPS tagging inaccuracies. Through the process of 3D elevation map alignment, the capabilities of seemingly unrelated software tools for aerial mapping are explored and compared. This paper presents the workflow capabilities of CAD inspection programs, reverse engineering software, and map analysis software tools approaching the 3D elevation maps as 3D models and maps at the same time. Furthermore, the utilization of enduring features — like vegetation instances occurring sparsely in some desert environments is studied in terms of suitability to provide a ground reference. Vegetation occurrences, which seldom grow in the deserts of the Arabian Peninsula, are inappropriate for precise mapping by LiDAR. Nevertheless, they create a prominent point cloud that may be used as a reference feature under specific consideration. Better map alignment allows for better 3D elevation map comparison, leading to further research of sandy deserts and their fluid-like behavior to increase renewable energy generation in such environments.

Autonomous navigation in wide outdoor areas faces challenges not present in structured environments. Simultaneous localization and mapping (SLAM) is a popular method of creating the map using the robot, and navigating in it. SLAM is difficult to achieve where there is no paved roads, buildings, and trees like in the sandy deserts. Autonomous robots cannot predict what is waiting behind the sand dune. Even if the terrain was mapped earlier, sand dunes can shift unpredictably. Therefore, mapping and GPS-based path planning should be done before every autonomous mission in such a dynamically shifting environment. Navigation can rely on GPS signals given the lack of obstructions. We develop a method for an Unmanned Aerial Vehicle (UAV) to autonomously take hundreds of images, convert terrain images into an elevation map, analyze the elevation map and generate traversable GPS waypoints for the Unmanned Ground Vehicle (UGV).

Atmospheric measurement techniques often require synchronous data capturing throughout the day, at the exact moment, more than capturing it at preset points in time. The system utilizes time stamps sent from the atomic clocks on navigation satellites. Time stamps received from the satellites by the GNSS receiver are turned into a triggering impulse. Impulses are needed for triggering the repurposed low-noise scientific cameras. The cameras must be mobile in an outdoor setup with a synchronized triggering system. However, the system is not limited to low-noise scientific cameras; it can be fitted to suit other applications requiring synchronous impulse, with a timestamping option. Systems comprise a microcontroller paired with a GNSS receiver which has access to the constant, one pulse per second, stream of GNSS satellite emitted time impulses. The GNSS receiver is connected to the camera and the microcontroller unit (MCU). 1PPS pin on the GNSS module is connected to a camera acting as its external trigger. The microcontroller is connected to the GNSS module accepting the NMEA sentences. Further, MCU communicates via USB with a data storage device, providing formatted time tagging data. The satellite impulse is directly converted to the camera trigger signal, allowing an indefinite number of devices to be triggered within a 30 nanosecond gap, with the possibility of triggering multiple low-noise cameras and other trigger-needing sensors distributed hundreds of meters or kilometers apart. The microprocessor generates the time tag without influencing the moment of the time of the trigger. GNSS module independently gives synchronous triggers while parallelly sending the data to the MCU to process it before the next satellite signal, which comes every second. We evaluate the solution on three commonly available prototyping boards in search of the least time difference between their trigger pulses.