G.V. Moiseev1, A.N. Chernyakov2, V.V. Ivanov3

1–3 Financial University under the Government of the Russian Federation (Moscow, Russia)
1 grg.moiseev@gmail.com

Problem. The group use of robots with nuclear radiation detectors plays a key role in ensuring nuclear safety and emergency cleanup of radioactive contamination. However, the existing process of searching for radiation sources using a group of robots requires a large number of calculations, which leads to low search efficiency.

Target. This paper proposes a method for collaboratively searching for an unknown radiation source by combining information from a group of robots and a free energy strategy with adaptive step size.

Results. It is proposed to use the principle of cognitive difference to selectively combine the measurement information of other robots to obtain a preliminary estimate of the probability distribution of the location of the radiation source. Based on information from se­veral robots, particles are fused in accordance with specified conditions to obtain precise parameters for the location of the radiation source. A step-by-step exchange of information between robots is assumed to solve the problem of searching for an unknown source of radiation using a free energy strategy with an adaptive step size.

Practice. Experimental results show that the search success rate using the proposed algorithm reaches 95%.

Moiseev G.V., Chernyakov A.N., Ivanov V.V. State of issue and mathematical model of multi-robot collaborative radioactive source search. Dynamics of complex systems. 2025. V. 19. № 5. P. 40−46. DOI: 10.18127/j19997493-202505-05 (in Russian).

1. Cho H.S., Woo T.H. Mechanical analysis of flying robot for nuclear safety and security control by radiological monitoring. Ann. Nucl. Energy 94. 2016. 138–143.
2. Xiao Y., Zhang C., Luo J., Yang C., Liu C. Integrating the radiation source position into a grid map of the environment using a mobile robot. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. 2020. 976, 164253. https://doi.org/10.1016/j.nima.2020.164253
3. IAEA Incident and Trafficking Database (ITDB), Incident and Trafficking Database：Combating illicit trafficking of radioactive materials for 25 year. Available online: https://www.iaea.org/sites/default/files/6112425.pdf (accessed on 1 February 2020).
4. Li B., Zhu Y., Wang Z., Li C., Peng Z., Ge L. Use of Multi-Rotor Unmanned Aerial Vehicles for Radioactive Source Search, Remote Sen­sing. 2018. 10 (5), 728.
5. Yuan L., Liu Y., Yu N., Fu X., Lei C. Medical response to a radiological accident involving an iridium-192 source in Nanjing. China, Ra­diation Protection Dosimetry. V. 182. № 1. P. 25–30.
6. Howse J.W., Ticknor L.O., Muske K.R. Least squares estimation techniques for position tracking of radioactive sources. Automatica. 2001. 37 (11). 1727–1737.
7. Gunatilaka A., Ristic B., Gailis R. On Localisation of a Radiological Point Source. Decision & Control. IEEE, Information. 2007b.
8. Rao N.S.V., Shankar M., Chin J.C., Yau D.K.Y., Srivathsan S., Iyengar S.S., Yang Y., Hou J.C. Identification of Low-Level Point Radiation Sources Using a Sensor Network. In Proceedings of the 2008 International Conference on Information Processing in Sensor Networks, St. Louis, MO, USA, 22–24 April 2008. P. 493–504.
9. Morelande M.R., Ristic B., Gunatilaka A. Detection and parameter estimation of multiple radioactive sources. In Proceedings of the 10th International Conference on Information Fusion, Quebec. AB, Canada. 2007. 9–12. 1–7.
10. Ristic B., Gunatilaka A., Rutten M. An information gain driven search for a radioactive point source. In Proceedings of the 10th International Conference on Information Fusion, Quebec. AB, Canada, 9–12 July 2007.
11. Ristic B., Gunatilaka A. Information driven localization of a radiological point source. Inf. Fusion. 2008. 9, 317–326.
12. Morelande M.R., Ristic B. Radiological Source Detection and Localization Using Bayesian Techniques. IEEE Trans. Signal Process. 2009. 57, 4220–4423.
13. Hite J., Mattingly J., Archer D., Willis M., Rowe A., Bray K., Carter J., Ghawaly J. Localization of a radioactive source in an urban environment using Bayesian Metropolis methods. Nucl. Instrum. Methods Phys. Res. A Accel. Spectrom. Detect. Assoc. Equip. 2019. 915, 82–9321.
14. Meutter P.D., Hoffma I. Bayesian source reconstruction of an anomalous Selenium-75 release at a nuclear research institute. J. Environ. Radioact. 2020. 218, 1062259.
15. Huo J., Liu M., Neusypin K.A., Liu H., Guo M., Xiao Y. Autonomous Search of Radioactive Sources through Mobile Robots. Sensors. 2020. 20 (12), 3461.
16. Xu P., Fu C., Tan Z., Cai X., Qin J. Robust radioactive sources research method using possibility particle filter, AIP Advances. 2021. 11 (8), 085308. https://doi.org/10.1063/5.0058860
17. Ristic B., Gunatilaka A., Rutten M. An information gain driven search for a radioactive point source. In Proceedings of the 10th International Conference on Information Fusion, Quebec, AB, Canada, 9–12 July 2007.
18. Ristic B., Gunatilaka A. Information driven localization of a radiological point source. 2008. Inf. Fusion 9, 317–326.
19. Wiedemann T., Manss C., Shutin D., Lilienthal A.J., Karolj V., Viseras A. Probabilistic modeling of gas diffusion with partial differential equations for multi-robot exploration and gas source localization. 2017. 6-8, 1–7.
20. Wiedemann T., Shutin D., Lilienthal A.J. Model-based gas source localization strategy for a cooperative multi-robot system – A probabilistic approach and experimental validation incorporating physical knowledge and model uncertainties, Robotics and Autonomous Systems 118, 2019. 66–79.
21. Steiner J.A., Bourne J.R., He X., Cropek D.M., Leang K.K. Chemical-Source Localization Using a Swarm of Decentralized Unmanned Aerial Vehicles for Urban/Suburban Environments, Park City, Utah, USA, October 8–11. 2019. V. 59162. V003T21A006.
22. Feng Q., Cai H., Yang Y., Xu J., Jiang M., Li F., Li X., Yan C. An experimental and numerical study on a multi-robot source localization method independent of airflow information in dynamic indoor, Sustainable Cities and Society. 2020. 53. 101897.
23. Ristic B., Skvortsov A. Intermittent Information-Driven Multi-Agent Area-Restricted Search. Entropy. 2020. 22 (6), 635.
24. Ristic B., Gilliam C., Moran W., Palmer J.L. Decentralised multi-platform search for a hazardous source in a turbulent flow. 2020. 58. 13–23.
25. Renzaglia A., Briñón-Arranz L. Search and Localization of a Weak Source with a Multi-robot Formation. Journal of Intelligent & Robotic Systems. 2020. 97 (3-4), 623–634.
26. Park M., Oh H. Cooperative information-driven source search and estimation for multiple agents. Information Fusion. 2020. 54, 72–84.
27. Song C., He Y., Ristic B., Lei X. Collaborative infotaxis: Searching for a signal-emitting source based on particle filter and Gaussian fitting, Robotics and Autonomous Systems 125, 103414. https://doi.org/10.1016/j.robot.2019.103414
28. Bos A., Rosenfeld A., Kron T., Errico F., Moscovitch M. Fundamentals of Radiation Dosimetry. Concepts & Trends in Medical Radiation Dosimetry. American Institute of Physics, 2011. 5–23.
29. Hol J.D., Schon T.B., Gustafsson F. On Resampling Algorithms for Particle Filters. IEEE Nonlinear Statistical Signal Processing Workshop. IEEE. 2007.