D. Batty L. Manes A. West M. Patel I. Caliskanelli P. Paoletti
In the nuclear industry, the need for improved reliability in current and future technology hinders the deployment of autonomous robotic systems. The following research aims to develop a method of reliably mapping a large environment and abstracting the map into a sparse node graph to create a more efficient data form. The proposed data form all…
PurchaseD. McGarrigle F. Warmer J. Lilburne M. Torrance
This paper reports on the analysis of potential rail-based maintenance systems when implemented into a Helical Advanced Stellarator (HELIAS) 5-B device. The main purpose of such a system would be to handle and exchange the internal vessel components, namely the breeding blanket segments, which are expected to be the largest and heaviest componen…
PublishedWenxing Liu Hanlin Niu Robert Skilton Joaquin Carrasco
When transferring a Deep Reinforcement Learning (DRL) model from simulation to the real world, the performance could be unsatisfactory since the simulation cannot imitate the real world well in many circumstances. This results in a long period of fine-tuning in the real world. This paper proposes a self-supervised vision-based DRL method that al…
PurchaseB. Devlin-Hill R. Calinescu J. Cámara I. Caliskanelli
Many complex domains would benefit from the services of Large-scale, Safety-verified, Always-on (LSA) robotic systems. However, existing large-scale solutions often forego the complex reasoning required for safety verification and prescient reasoning in favour of scalability. We propose a method of partitioning the task domain to enable scalabil…
PurchaseMichal Staniaszek Lara Brudermuller Raunak Bhattacharyya Bruno Lacerda Nick Hawes
We consider planning problems where a robot must visit a large set of locations to complete a task at each one. Our focus is problems where the difficulty of each task, and thus its duration, can be predicted, but not fully known in advance. We propose a general Markov decision process (MDP) model for difficulty-aware problems, and propose varia…
PurchaseWenxing Liu Hanlin Niu Wei Pan Guido Herrmann Joaquin Carrasco
Sim-and-real training is a promising alternative to sim-to-real training for robot manipulations. However, the current sim-and-real training is neither efficient, i.e., slow convergence to the optimal policy, nor effective, i.e., sizeable real-world robot data. Given limited time and hardware budgets, the performance of sim-and-real training is …
PurchaseKwame Akowua Lee Aucott David Wallis Raphael Hery Remi Carrat Emmanuel Brau Chris Lamb Heather Lewtas Helena Livesey.
ITER In-Vessel Components (IVCs) will have limited lifetimes and need to be maintained and/or replaced during the operational life of ITER. IVCs are attached to the plant cooling water system via pipework to enable active cooling of the components during plasma operations. When maintenance is required, Remote Handling Systems (RHS) will be used …
PublishedThomas Stokes Mirjana Damjanovic Joe Berriman Stephen Reynolds
Investigations were undertaken into the thermal treatment of beryllium and tungsten to see if these materials can be detritiated in the Material Detritiation Facility (MDF) at UKAEA, allowing for the declassification of intermediate level waste (ILW) to low level waste (LLW). When heated in oxygen, both tungsten and beryllium readily oxidise, wi…
Preprint PublishedLuca Stefanescu Max Boleininger Pui-Wai Ma
We investigated the athermal irradiation-induced swelling and creep in iron subjecting to the application of external uniaxial stress. We studied this through atomic scale simulations using the creation-relaxation algorithm. We also calculated the defect relaxation volume density tensors (or eigenstrain) as a function of external uniaxial stress. B…
Preprint PublishedP.A. Ferreirós S.O. von Tiedemann N. Parkes D. Gurah D.J.M. King P. Norman M.R. Gilbert A.J. Knowles
Refractory high-entropy alloys (RHEAs) with high melting points and low neutron absorption cross-section are sought for generation-IV fission and fusion reactors. A high throughput computational screening tool, Alloy Search and Predict (ASAP), was used to identify promising RHEA candidates from over 1 million four-element equimolar combinations. Th…
Preprint Published