Markov decision processes with unknown state feature values for safe exploration using Gaussian processes
When exploring an unknown environment, a mobile robot must decide where to observe next. It must do this whilst minimising the risk of failure, by only exploring areas that it expects to be safe. In this context, safety refers to the robot remaining in regions where critical environment features (e....
Main Authors: | , , , , , |
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Format: | Conference item |
Language: | English |
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Institute of Electrical and Electronics Engineers
2021
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_version_ | 1826305629608738816 |
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author | Budd, M Lacerda, B Duckworth, P West, A Lennox, B Hawes, N |
author_facet | Budd, M Lacerda, B Duckworth, P West, A Lennox, B Hawes, N |
author_sort | Budd, M |
collection | OXFORD |
description | When exploring an unknown environment, a mobile robot must decide where to observe next. It must do this whilst minimising the risk of failure, by only exploring areas that it expects to be safe. In this context, safety refers to the robot remaining in regions where critical environment features (e.g. terrain steepness, radiation levels) are within ranges the robot is able to tolerate. More specifically, we consider a setting where a robot explores an environment modelled with a Markov decision process, subject to bounds on the values of one or more environment features which can only be sensed at runtime. We use a Gaussian process to predict the value of the environment feature in unvisited regions, and propose an estimated Markov decision process, a model that integrates the Gaussian process predictions with the environment model transition probabilities. Building on this model, we propose an exploration algorithm that, contrary to previous approaches, considers probabilistic transitions and explicitly reasons about the uncertainty over the Gaussian process predictions. Furthermore, our approach increases the speed of exploration by selecting locations to visit further away from the currently explored area. We evaluate our approach on a real-world gamma radiation dataset, tackling the challenge of a nuclear material inspection robot exploring an a priori unknown area. |
first_indexed | 2024-03-07T06:35:44Z |
format | Conference item |
id | oxford-uuid:f790bb7f-5f16-4aa2-af7f-43f759a57648 |
institution | University of Oxford |
language | English |
last_indexed | 2024-03-07T06:35:44Z |
publishDate | 2021 |
publisher | Institute of Electrical and Electronics Engineers |
record_format | dspace |
spelling | oxford-uuid:f790bb7f-5f16-4aa2-af7f-43f759a576482022-03-27T12:43:38ZMarkov decision processes with unknown state feature values for safe exploration using Gaussian processesConference itemhttp://purl.org/coar/resource_type/c_5794uuid:f790bb7f-5f16-4aa2-af7f-43f759a57648EnglishSymplectic ElementsInstitute of Electrical and Electronics Engineers2021Budd, MLacerda, BDuckworth, PWest, ALennox, BHawes, NWhen exploring an unknown environment, a mobile robot must decide where to observe next. It must do this whilst minimising the risk of failure, by only exploring areas that it expects to be safe. In this context, safety refers to the robot remaining in regions where critical environment features (e.g. terrain steepness, radiation levels) are within ranges the robot is able to tolerate. More specifically, we consider a setting where a robot explores an environment modelled with a Markov decision process, subject to bounds on the values of one or more environment features which can only be sensed at runtime. We use a Gaussian process to predict the value of the environment feature in unvisited regions, and propose an estimated Markov decision process, a model that integrates the Gaussian process predictions with the environment model transition probabilities. Building on this model, we propose an exploration algorithm that, contrary to previous approaches, considers probabilistic transitions and explicitly reasons about the uncertainty over the Gaussian process predictions. Furthermore, our approach increases the speed of exploration by selecting locations to visit further away from the currently explored area. We evaluate our approach on a real-world gamma radiation dataset, tackling the challenge of a nuclear material inspection robot exploring an a priori unknown area. |
spellingShingle | Budd, M Lacerda, B Duckworth, P West, A Lennox, B Hawes, N Markov decision processes with unknown state feature values for safe exploration using Gaussian processes |
title | Markov decision processes with unknown state feature values for safe exploration using Gaussian processes |
title_full | Markov decision processes with unknown state feature values for safe exploration using Gaussian processes |
title_fullStr | Markov decision processes with unknown state feature values for safe exploration using Gaussian processes |
title_full_unstemmed | Markov decision processes with unknown state feature values for safe exploration using Gaussian processes |
title_short | Markov decision processes with unknown state feature values for safe exploration using Gaussian processes |
title_sort | markov decision processes with unknown state feature values for safe exploration using gaussian processes |
work_keys_str_mv | AT buddm markovdecisionprocesseswithunknownstatefeaturevaluesforsafeexplorationusinggaussianprocesses AT lacerdab markovdecisionprocesseswithunknownstatefeaturevaluesforsafeexplorationusinggaussianprocesses AT duckworthp markovdecisionprocesseswithunknownstatefeaturevaluesforsafeexplorationusinggaussianprocesses AT westa markovdecisionprocesseswithunknownstatefeaturevaluesforsafeexplorationusinggaussianprocesses AT lennoxb markovdecisionprocesseswithunknownstatefeaturevaluesforsafeexplorationusinggaussianprocesses AT hawesn markovdecisionprocesseswithunknownstatefeaturevaluesforsafeexplorationusinggaussianprocesses |