Gas concentration mapping and source localization for environmental monitoring through unmanned aerial systems using model-free reinforcement learning agents

There are three primary objectives of this work; first: to establish a gas concentration map; second: to estimate the point of emission of the gas; and third: to generate a path from any location to the point of emission for UAVs or UGVs. A mountable array of MOX sensors was developed so that the an...

Full description

Saved in:
Bibliographic Details
Main Authors: ul Husnain, Anees, Mokhtar, Norrima, Shah, Noraisyah Mohamed, Dahari, Mahidzal, Azmi, Amirul Asyhraff, Iwahashi, Masahiro
Format: Article
Published: Public Library of Science 2024
Subjects:
Online Access:http://eprints.um.edu.my/45569/
https://doi.org/10.1371/journal.pone.0296969
Tags: Add Tag
No Tags, Be the first to tag this record!
id my.um.eprints.45569
record_format eprints
spelling my.um.eprints.455692024-10-29T08:24:02Z http://eprints.um.edu.my/45569/ Gas concentration mapping and source localization for environmental monitoring through unmanned aerial systems using model-free reinforcement learning agents ul Husnain, Anees Mokhtar, Norrima Shah, Noraisyah Mohamed Dahari, Mahidzal Azmi, Amirul Asyhraff Iwahashi, Masahiro QA75 Electronic computers. Computer science TK Electrical engineering. Electronics Nuclear engineering There are three primary objectives of this work; first: to establish a gas concentration map; second: to estimate the point of emission of the gas; and third: to generate a path from any location to the point of emission for UAVs or UGVs. A mountable array of MOX sensors was developed so that the angles and distances among the sensors, alongside sensors data, were utilized to identify the influx of gas plumes. Gas dispersion experiments under indoor conditions were conducted to train machine learning algorithms to collect data at numerous locations and angles. Taguchi's orthogonal arrays for experiment design were used to identify the gas dispersion locations. For the second objective, the data collected after pre-processing was used to train an off-policy, model-free reinforcement learning agent with a Q-learning policy. After finishing the training from the training data set, Q-learning produces a table called the Q-table. The Q-table contains state-action pairs that generate an autonomous path from any point to the source from the testing dataset. The entire process is carried out in an obstacle-free environment, and the whole scheme is designed to be conducted in three modes: search, track, and localize. The hyperparameter combinations of the RL agent were evaluated through trial-and-error technique and it was found that epsilon = 0.9, gamma = 0.9 and alpha = 0.9 was the fastest path generating combination that took 1258.88 seconds for training and 6.2 milliseconds for path generation. Out of 31 unseen scenarios, the trained RL agent generated successful paths for all the 31 scenarios, however, the UAV was able to reach successfully on the gas source in 23 scenarios, producing a success rate of 74.19%. The results paved the way for using reinforcement learning techniques to be used as autonomous path generation of unmanned systems alongside the need to explore and improve the accuracy of the reported results as future works. Public Library of Science 2024-02 Article PeerReviewed ul Husnain, Anees and Mokhtar, Norrima and Shah, Noraisyah Mohamed and Dahari, Mahidzal and Azmi, Amirul Asyhraff and Iwahashi, Masahiro (2024) Gas concentration mapping and source localization for environmental monitoring through unmanned aerial systems using model-free reinforcement learning agents. PLoS ONE, 19 (2). e0296969. ISSN 1932-6203, DOI https://doi.org/10.1371/journal.pone.0296969 <https://doi.org/10.1371/journal.pone.0296969>. https://doi.org/10.1371/journal.pone.0296969 10.1371/journal.pone.0296969
institution Universiti Malaya
building UM Library
collection Institutional Repository
continent Asia
country Malaysia
content_provider Universiti Malaya
content_source UM Research Repository
url_provider http://eprints.um.edu.my/
topic QA75 Electronic computers. Computer science
TK Electrical engineering. Electronics Nuclear engineering
spellingShingle QA75 Electronic computers. Computer science
TK Electrical engineering. Electronics Nuclear engineering
ul Husnain, Anees
Mokhtar, Norrima
Shah, Noraisyah Mohamed
Dahari, Mahidzal
Azmi, Amirul Asyhraff
Iwahashi, Masahiro
Gas concentration mapping and source localization for environmental monitoring through unmanned aerial systems using model-free reinforcement learning agents
description There are three primary objectives of this work; first: to establish a gas concentration map; second: to estimate the point of emission of the gas; and third: to generate a path from any location to the point of emission for UAVs or UGVs. A mountable array of MOX sensors was developed so that the angles and distances among the sensors, alongside sensors data, were utilized to identify the influx of gas plumes. Gas dispersion experiments under indoor conditions were conducted to train machine learning algorithms to collect data at numerous locations and angles. Taguchi's orthogonal arrays for experiment design were used to identify the gas dispersion locations. For the second objective, the data collected after pre-processing was used to train an off-policy, model-free reinforcement learning agent with a Q-learning policy. After finishing the training from the training data set, Q-learning produces a table called the Q-table. The Q-table contains state-action pairs that generate an autonomous path from any point to the source from the testing dataset. The entire process is carried out in an obstacle-free environment, and the whole scheme is designed to be conducted in three modes: search, track, and localize. The hyperparameter combinations of the RL agent were evaluated through trial-and-error technique and it was found that epsilon = 0.9, gamma = 0.9 and alpha = 0.9 was the fastest path generating combination that took 1258.88 seconds for training and 6.2 milliseconds for path generation. Out of 31 unseen scenarios, the trained RL agent generated successful paths for all the 31 scenarios, however, the UAV was able to reach successfully on the gas source in 23 scenarios, producing a success rate of 74.19%. The results paved the way for using reinforcement learning techniques to be used as autonomous path generation of unmanned systems alongside the need to explore and improve the accuracy of the reported results as future works.
format Article
author ul Husnain, Anees
Mokhtar, Norrima
Shah, Noraisyah Mohamed
Dahari, Mahidzal
Azmi, Amirul Asyhraff
Iwahashi, Masahiro
author_facet ul Husnain, Anees
Mokhtar, Norrima
Shah, Noraisyah Mohamed
Dahari, Mahidzal
Azmi, Amirul Asyhraff
Iwahashi, Masahiro
author_sort ul Husnain, Anees
title Gas concentration mapping and source localization for environmental monitoring through unmanned aerial systems using model-free reinforcement learning agents
title_short Gas concentration mapping and source localization for environmental monitoring through unmanned aerial systems using model-free reinforcement learning agents
title_full Gas concentration mapping and source localization for environmental monitoring through unmanned aerial systems using model-free reinforcement learning agents
title_fullStr Gas concentration mapping and source localization for environmental monitoring through unmanned aerial systems using model-free reinforcement learning agents
title_full_unstemmed Gas concentration mapping and source localization for environmental monitoring through unmanned aerial systems using model-free reinforcement learning agents
title_sort gas concentration mapping and source localization for environmental monitoring through unmanned aerial systems using model-free reinforcement learning agents
publisher Public Library of Science
publishDate 2024
url http://eprints.um.edu.my/45569/
https://doi.org/10.1371/journal.pone.0296969
_version_ 1814933245663379456
score 13.211869