Principal investigator: Bruno Benevit
Original title: Applications of unmanned aerial vehicle (UAV) in road safety, traffic and highway infrastructure management: Recent advances and challenges
Authors: Fatma Outay, Hanan Abdullah Mengash and Muhammad Adnan
Location of the Intervention:
Sample Size: 91 studies
Sector: Transportation Economics
Primary Variable of Interest: Road traffic
Type of Intervention: Drones
Methodology: Systematic review
Summary
Unmanned aerial vehicles, popularly known as drones, are widely used in surveillance and improvement applications in various areas. Land transportation is one of the sectors that benefits most from this tool. This article presents a review of the latest advances in drones for the road transport sector, highlighting three functionalities: improved road safety, traffic monitoring, and infrastructure management. The article discusses advances in computer vision algorithms for extracting information from videos and images captured by drones, relating them to improvements in the three main functionalities analyzed in the sector. The authors also discuss the barriers associated with the widespread implementation of drones and possible solutions to overcome them.
- Policy Problem
The use of drones has become popular in many sectors, allowing tasks to be performed more safely and with lower environmental costs compared to piloted aviation operations (OUTAY; MENGASH; ADNAN, 2020). In this context, the market for civil and commercial drones has grown at a rate of 19% (JOSHI, 2019), and is associated with at least 100 jobs in the United States alone. Their uses are diverse, encompassing areas such as real estate, insurance, agriculture, healthcare, and monitoring.
In the transportation sector, this tool provides a range of solutions for its improvement. In particular, this technology allows for the monitoring of traffic and driver behavior through the capture of data collected from cameras attached to drones. This data can be used for a variety of purposes, such as surveillance and monitoring, recognition of traffic violations, assistance in managing traffic congestion, optimization of traffic signals, and extraction of vehicle trajectories to answer research questions related to accident risk assessment, among others.
Recognizing the advantages of this technology, the United States Congress mandated the integration of small drones into airspace in 2012. Since then, companies like Amazon have begun using them for deliveries. This has led to an expansion in funding and research on drones, especially in the transportation sector. Therefore, it becomes relevant to understand how drones are used, their advantages, barriers to implementation, and areas for improvement.
- Method
The methodology of this article focused on reviewing the literature related to the use of drones in three functionalities for the transportation sector: road safety, traffic monitoring and management, and road infrastructure management.
Thus, the authors aimed to gather and compile all relevant materials available online, including journal articles, conference papers, policy documents, technical reports, project deliverables, book chapters, and web pages. The temporal scope of the article search considered the period from 2000 to 2020 in the SCOPUS and Google Scholar databases. The studies obtained were selected based on their relevance to the specific topic of transportation.
Following this, the research literature was summarized in tables, emphasizing cases with a higher number of studies and highlighting the evolution of methods and technologies. Patents were not explicitly considered in the review. Furthermore, it is worth noting that the review focused on applications performed by small drones, generally equipped with propellers, which allow takeoff from any point, rather than fixed-wing drones that require facilities such as runways.
- Road safety
Evidence in the literature on the use of drones for road safety highlights two main areas of application: accident investigation and risk assessment. Regarding accident investigation, the technology has enabled significant advances in reconstructing scenes from photographs and videos captured by drones. Although in the past there were challenges related to image capture, such as filming angles and altitude, the improvement of drones and drone technology has made significant progress. software Image processing has enabled greater precision. Methodologies for this purpose involve flight planning, data collection and transfer, image processing to generate 3D models, and system validation. Despite these contributions, studies point to the need for large-scale implementation and comparisons between different systems to optimize scene reconstruction.
Regarding risk assessment, the use of drones has enabled detailed analyses of vehicle trajectories, overcoming limitations of traditional methods, such as fixed angles of cameras mounted on physical structures. According to the authors, recent studies have developed algorithms to identify hazardous events and assess collision risks, incorporating measures such as time to collision. Some proposals utilize multiple drones and vehicular networks for more effective monitoring, while others invest in embedded vision systems for automatic detection of abnormal situations. Additionally, efforts focused on prioritization have also been identified, with the adoption of terrain modeling and evaluation of visibility distances in critical areas.
- Traffic monitoring and management
Regarding traffic monitoring and management, the literature shows that drones have played a significant role in traffic monitoring and management, especially in video processing for extracting traffic parameters. This is due to advances in computer vision algorithms, such as image feature extraction and deep learning (deep learningWith the advent of drone technology, it became possible to detect vehicles, track their trajectories, and calculate parameters such as speed, density, and flow. Initial studies used fixed-wing drones, which were large and expensive, but advances in rotary drone technology, which are lighter and more affordable, have broadened their application (OUTAY; MENGASH; ADNAN, 2020). These devices have enabled both image capture and real-time and/or other types of analysis. offline.
Drones have also been employed in traffic flow analysis, contributing to the study of road geometries, flow behavior, and vehicle tracking models. Data extracted from aerial videos enable analyses such as gap acceptance at intersections, identification of shock waves at traffic lights, and evaluation of roundabout performance. Furthermore, the application of machine learning models has allowed for the understanding of complex traffic behaviors in dynamic and congested urban scenarios. Recent studies also highlight the potential of the widespread use of drones (“swarms”) to capture large-scale data, encompassing complex urban networks and offering new perspectives for understanding congestion and its propagation.
- Road infrastructure management
The use of drones in road infrastructure management has been explored in areas such as bridge inspection and pavement condition monitoring. For bridge inspections, drones offer benefits such as time savings, reduced traffic disruptions, and less need for specialized equipment. Drones equipped with high-resolution cameras and infrared thermography technology can efficiently identify structural damage and monitor the condition of bridges. Advanced image processing methods, such as enhanced edge detection algorithms and deep neural networks, have demonstrated greater accuracy in detecting cracks and other defects. Therefore, this technology provides a safer and more economical alternative to traditional methods (OUTAY; MENGASH; ADNAN, 2020).
In pavement monitoring, drones are being used to map road surfaces, identify irregularities, and assess conditions such as cracks and deformations. The integration of images captured by drones with tools such as ground-penetrating radar and photogrammetry has shown promising results in obtaining detailed data on infrastructure. Additionally, specific algorithms have been developed to analyze three-dimensional point clouds, allowing the reconstruction of digital road models and the detection of distress with high precision. Despite these advances, the authors highlight that challenges such as the need for rigorous system validation and the technical complexity for large-scale applications still limit the widespread adoption of this technology.
- Regulations, Challenges, and Lessons in Public Policy
In recent years, regulatory advancements, such as those proposed by the European Union, have aimed to harmonize the use of drones and associated technologies in urban contexts. However, the large-scale deployment of drones faces significant challenges, especially related to airspace regulations and technological limitations. Regulations often require drones to operate within the operator's visual field and impose restrictions on weight, flight altitude, and nighttime operations, in addition to demanding specific training and certifications. Although some nations, such as Spain and France, have adopted more flexible regulations, the safe integration of drones into urban environments requires advancements in fault detection systems and adverse weather conditions. Furthermore, the adoption of technological platforms for air traffic management is necessary, such as the cloud-based system implemented in China.
In addition to regulatory challenges, technological limitations, such as short battery life, also restrict the use of drones. Advances in lithium batteries and hydrogen fuel cells, as well as the use of solar energy, have been explored to increase flight time. Simultaneously, route planning and energy optimization algorithms have been developed to maximize mission efficiency. However, issues such as cybersecurity and social acceptance remain challenges, highlighting the need for approaches that balance automation and human interaction in air traffic management.
The evidence from the drone literature presented in this article helps to understand the challenges and possible solutions for the large-scale adoption of drones, providing input for the formulation of public policies that encourage the safe and efficient use of this technology. Despite the technical and regulatory challenges, drones have great potential to increase productivity and reduce costs in the transportation sector, significantly transforming the safety, monitoring, and management of road infrastructure.
References
JOSHI, D. Drone technology uses and applications for commercial, industrial and military drones in 2020 and the future: Business Insider Intelligence research report preview of Drones for the Enterprise. [sl: sn]. . Accessed on: 13 Jan. 2025.
OUTAY, F.; MENGASH, HA; ADNAN, M. Applications of unmanned aerial vehicle (UAV) in road safety, traffic and highway infrastructure management: Recent advances and challenges. Transportation Research Part A: Policy and Practice, v. 141, p. 116–129, nov. 2020.
