Drones for Inspection of Highway Tunnels and Bridges

Drone technologies are gaining popularity in civil engineering, particularly for inspections in areas with limited satellite signals. UAVs can assist in inspecting bridges, road and rail tunnels, ventilation shafts, pipes, and enclosed culverts, both externally and internally.

Regular inspections are essential, and their duration varies based on the size of the infrastructure. Without using modern inspection methods, this can prove very costly and time-consuming. Furthermore, the naked eye cannot detect all potential defects. Utilizing optical methods with high-precision and high-sensitivity cameras, drones are ideal for conducting initial assessments, thereby reducing costs, time, and the risk to specialized inspectors and other technicians in danger.

Members of the Fly4Future team have been involved in the successful development of a system for precise localization and navigation in GNSS-denied environments. The innovative technology is designed to capture high-quality images of specific locations in the complex tunnel environment with exceptional accuracy and efficiency.

The system’s ability to capture detailed images was tested under authentic conditions during the temporary closure of the Blanka Tunnel, the longest highway tunnel in the Czech Republic. This real-world test validated the system’s ability to operate safely in challenging conditions such as low light and dust.

It is also possible to use Fly4Future drones equipped with this advanced technology in the narrow auxiliary tunnels designed to vent exhaust emissions. The toxic environment of these ventilation tunnels poses a risk to the maintenance team. Our autonomous drones can accelerate inspections during active tunnel operations, reducing health risks to human inspectors by minimizing potential exposure to hazardous fumes, and potentially changing traditional maintenance practices.

When inspecting bridges, it is important to note that the DNSS signal may not always be fully accessible. In order for a drone to effectively locate damage in close proximity to the bridge structure, it must be able to fly under the bridge structure and transition between areas with full GNSS signal and areas with insufficient or completely denied GNSS signal. This navigation process requires careful planning and a flexible approach to ensure that accurate positioning data is maintained throughout the flight.

While remotely operated equipment runs the risk of crashing into the bridge due to the human factor, Fly4Future autonomous drones can quickly and easily navigate around the bridge structure using advanced algorithms and flexible obstacle avoidance technology. This reduces the risk of collisions and increases overall operational efficiency. In addition, the use of a swarm of Fly4Future drones contributes to the overall shorter time frame required for inspection, as well as saving resources that would otherwise be spent on manpower and scaffolding.