Real-Time Gamma Radioactive Source Localization by Data Fusion of 3D-LiDAR Terrain Scan and Radiation Data from Semi-Autonomous UAV Flights

Abstract

Rapid and accurate reconnaissance in the event of radiological and nuclear (RN) incidents or attacks is vital to launch an appropriate response. This need is made stronger by the increasing threat of RN attacks on soft targets and critical infrastructure in densely populated areas. In such an event, even small radioactive sources can cause major disruption to the general population. In this work, we present a real-time radiological source localization method based on an optimization problem considering a background and radiation model. Supported by extensive real-world experiments, we show that an airborne system using this method is capable for reliably locating category 3–4 radioactive sources according to IAEA safety standards in real time from altitudes up to 150 m. A sensor bundle including a LiDAR sensor, a Gamma probe as well as a communication module was mounted on a UAV that served as a carrier platform. The method was evaluated on a comprehensive set of test flights, including 28 flight scenarios over 316 minutes using three different radiation sources. All additional gamma sources were correctly detected, multiple sources were detected if they were sufficiently separated from each other, with the distance between the true source position and the estimated source averaging 17.1 m. We also discuss the limitations of the system in terms of detection limit and source separation.

Civil Integrated Management (CIM) for Advanced Level Applications to Transportation Infrastructure: A State-of-the-Art Review

“…The precision of the sensor, determined by its resolution, is critical in defining the accuracy with which traffic infrastructure elements can be mapped and analyzed. Higher-resolution sensors provide finer details, essential for the accurate recognition of elements like road signs, signals, and markings, which are crucial for safety and efficient traffic management [93,94]. Three-dimensional scanning, which encompasses technologies such as LiDAR, allows for detailed measurements and high-fidelity models, particularly with terrestrial setups where the equipment is stationary.…”

A Real-Time Localization Algorithm for Unmanned Aerial Vehicle Based on Continuous Images Processing

“…Given that the ground coordinates of two different matching points in the image captured by the UAV at a certain location are x q1 , y q1 , z q1 and x q2 , y q2 , z q2 , calculate the ground coordinates of the UAV at that point. The calculation method is shown in formula (3).…”

“…Unlike pilot-navigated UAVs, autonomous control systems heavily rely on accurate feedback of the vehicle's position. Current common technologies for UAV localization include Global Positioning System (GPS) [1,2], laser radar [3,4], ultrasound [5], Ultra-Wideband (UWB) [6], radio frequency [7,8], and visual methods [9,10]. While GPS is commonly employed for obtaining location information in open areas, its performance degrades when there is interference with GPS signals.…”

Radioactive source localization employing resistive electrode array (REA) detector

“…Other potential uses of the REA localization capability is in Radioisotope Identification (RIID) in health safety and national security [6]. Various detectors have been used in radioactive source localization [7][8][9][10][11][12][13][14]: radiosensitive films, at panel detectors (Electronic Portal Imaging Device (EPID)), gamma camera, photon counting detectors, scintillators, and others. Typically the detector is at a fixed position and radioactive sources are either static or moving.…”

“…Typically the detector is at a fixed position and radioactive sources are either static or moving. However, in some applications the detector itself may be moved by a robot or a drone [12,14]. In medical applications the main challenges of radioactive source tracking are: dynamic range of operation and accuracy of detection, as well as practicality of the device usage under clinical environment such as: mechanical clearance, simplicity of operation, robustness of data analysis.…”