The local entity, Diputación Foral de Bizkaia, decided to use Hovering Solution´s autonomous aerial robot, one of the 3 companies in the world offering autonomous drone capabilities in GPS-denied areas.
The advantage of using autonomous drones for these types of inspections is that they can perform missions without a pilot, external communication with any device, and also in absence of GPS signal or ambience light. That is, the autonomous capacity is embedded within the aircraft itself, providing a competitive advantage as it is able to sort out flooded areas, obstacles and irregularities along flight path.
The main technical difficulty resides in the need to replace the valuable information provided by satellites, which is used by conventional drones to determine position and speed at any time with high accuracy.
By contrast, Hovering Solution´s technology has developed a proprietary hardware and software. It relies on multiple on-board sensors such as LIDAR, ultra-sound, infrared, image and inertial units (IMU), redundant and thermically calibrated. A high speed processor is then capable to read and correlate all the information in real time, and provide an estimation of speed and position; that is, where the drone is and how fast it is moving. The presence of magnetic fields cause by minerals and metals represents and additional challenge and do not allow the use electric compasses, otherwise valuable in outdoor flights.
The flights are carried out without any previous map or knowledge of the infrastructure. The robot generates a map as it flies, which serves for navigation and is also the base for the 3D model delivered to client after the flight.
The aircraft can carry two types of missions: one-way and round-trip. One-way flights are more efficient, as the whole battery life is used to capture data, but it requires two access points to launch and recover the unit. Round-trips flights are suited for missions where only one access is open, or to cover very long distances accessing from both sides, flying up to the center, and return. The aircraft used in Lezama has an autonomy of 29 minutes, enough to digitize up to a few kilometers in one single flight.
Hovering Solutions also has a larger version, with a range of 7 kilometers, an alleged world record on underground flight, which was presented together with Iberdrola in the Hydro 2022 congress in Strasbourg, France, on April 2022. On the other hand, Hovering Solutions is also working in a smaller version of the robot, aimed to fly in small-diameter pipes. This compact drone will have just 22cm between rotors and will be ready to fly along 80-120cm pipes by the second half of 2023.