Professor Nigel Crook
Associate Dean: Research and Knowledge Exchange (ADRKE)
School of Engineering, Computing and Mathematics
Research
Centres and institutes
Groups
Projects as Principal Investigator, or Lead Academic if project is led by another Institution
- Get strong to fight childhood cancer: an exercise intervention for children and adolescents undergoing anti-cancer treatment (FORTE-e) (led by UNIVERSITAETSMEDIZIN DER JOHANNES GUTENBERG-UNIVERSITAET MAINZ) (led by HLS) (01/03/2021 - 31/08/2026), funded by: European Commission, funding amount received by Brookes: £19,472
- Innovation Caucus - ‘Understanding the Funding and Investment of Diverse Innovators in the UK: A Market Analysis - uplift of project (original costing WT779308) (led by OBBS) (09/11/2020 - 08/06/2021), funded by: Economic & Social Research Council (ESRC), funding amount received by Brookes: £5,108
Publications
Journal articles
-
Crook N, Nugent S, Rolf M, Baimel A, Raper R, 'Computing morality: Synthetic ethical decision making and behaviour'
Cognitive Computation and Systems 3 (2) (2021) pp.79-82
ISSN: 2517-7567 eISSN: 2517-7567AbstractPublished hereWe find ourselves at a unique point of time in history. Following over two millennia of debate amongst some of the greatest minds that ever existed about the nature of morality, the philosophy of ethics and the attributes of moral agency, and after all that time still not having reached consensus, we are coming to a point where artificial intelligence (AI) technology is enabling the creation of machines that will possess a convincing degree of moral competence. The existence of these machines will undoubtedly have an impact on this age old debate, but we believe that they will have a greater impact on society at large, as AI technology deepens its integration into the social fabric of our world. The purpose of this special issue on Computing Morality is to bring together different perspectives on this technology and its impact on society. The special issue contains four very different and inspiring contributions.
-
Crook N, Corneli J, 'The anatomy of moral agency: A theological and neuroscience inspired model of virtue ethics'
Cognitive Computation and Systems 3 (2) (2021) pp.109-122
ISSN: 2517-7567 eISSN: 2517-7567AbstractPublished here Open Access on RADARVirtuosA (‘virtuous algorithm’) is introduced, a model in which artificial intelligence (AI) systems learn ethical behaviour based on a framework adapted from Christian philosopher Dallas Willard and brought together with associated neurobiological structures and broader systems thinking. To make the inquiry concrete, the authors present a simple example scenario that illustrates how a robot might acquire behaviour akin to the virtue of kindness that can be attributed to humans. References to philosophical work by Peter Sloterdijk help contextualise Willard’s virtue ethics framework. The VirtuosA architecture can be implemented using state-of-the-art computing practices and plausibly redescribes several concrete scenarios implemented from the computing literature and exhibits broad coverage relative to other work in ethical AI. Strategies are described for using the model for systems evaluation —particularly the role of ‘embedded evaluation’ within the system—and its broader application as a meta-ethical device is discussed.
-
Aldea A, Crook N, Duce D, Marshall P, Martin C, Sutton D, 'Reflections on the evolution of the teaching of programming to undergraduates at Oxford Brookes University'
Brookes eJournal of Learning and Teaching 7 (1) (2015)
ISSN: 1744-7747AbstractPublished hereUndergraduate computing courses inevitably include a high degree of regeneration in order to keep abreast of this rapidly changing field. Introductory programming modules in particular need to adapt to changing trends and languages. Until recently, the focus of debate within the Oxford Brookes University curriculum has therefore been on the course content, but since 2012 there has been a major change in the method of delivery through the introduction of a new apprenticeship model. This paper seeks to reflect on this, and other recent changes which have led to improved student engagement and results. The data is limited however, and so the results presented here are not conclusive.
-
Cheng M, Zheng S, Lin WY, Vineet V, Sturgess P, Crook N, Mitra NJ, Torr P, 'Imagespirit:verbal guided image parsing'
ACM Transactions on Graphics 34 (1) (2014)
ISSN: 0730-0301AbstractPublished hereHumans describe images in terms of nouns and adjectives while algorithms
operate on images represented as sets of pixels. Bridging this gap between
how humans would like to access images versus their typical representation
is the goal of image parsing, which involves assigning object and attribute
labels to pixel. In this paper we propose treating nouns as object labels and
adjectives as visual attribute labels. This allows us to formulate the image
parsing problem as one of jointly estimating per-pixel object and attribute
labels from a set of training images. We propose an efficient (interactive
time) solution. Using the extracted labels as handles, our system empowers
a user to verbally refine the results. This enables hands-free parsing of an
image into pixel-wise object/attribute labels that correspond to human semantics.
Verbally selecting objects of interests enables a novel and natural
interaction modality that can possibly be used to interact with new generation
devices (e.g. smart phones, Google Glass, living room devices). We
demonstrate our system on a large number of real-world images with varying
complexity. To help understand the tradeoffs compared to traditional
mouse based interactions, results are reported for both a large scale quantitative
evaluation and a user study.
-
Smith C, Crook N, Charlton D, Boye J, Pulman S, Santos de la Camara R, Turunen M, Benyon D, 'Interaction Strategies for an Affective Conversational Agent'
Presence: Teleoperators and Virtual Environments 20 (5) (2012)
ISSN: 1054-7460Published here -
Crook N, Field D, Smith C, Harding S, Pulman S, Cavazza M, Moore R, Boye J, 'Generating context-sensitive ECA responses to user barge-in interruptions'
Journal on Multimodal User Interfaces 6 (40940) (2012) pp.13-25
ISSN: 1783-7677AbstractPublished hereWe present an Embodied Conversational Agent(ECA) that incorporates a context-sensitive mechanism for handling user barge-in. The affective ECA engages the user in social conversation, and is fully implemented. We will use actual examples of system behaviour to illustrate. The ECA is designed to recognise and be empathetic to the emotional state of the user. It is able to detect, react quickly to, and then follow up with considered responses to different kinds of user interruptions. The design of the rules which enable the ECA to respond intelligently to different types of interruptions was informed by manually analysed real data from human-human dialogue. The rules represent recoveries from interruptions as two-part structures: an address followed by a resumption. The system is robust enough to man- age long, multi-utterance turns by both user and system, which creates good opportunities for the user to interrupt while the ECA is speaking.
-
Crook N, Goh W, 'Nonlinear transient computation as a potential 'kernel trick' in cortical processing'
BioSystems 94 (1) (2008) pp.55-59
ISSN: 0303-2647 eISSN: 1872-8324AbstractEvidence has been found for the presence of chaotic dynamics at all levels of the mammalian brain. This has led to some searching questions about the potential role that nonlinear dynamics may have in neural information processing. We propose that chaos equips the brain with the equivalent of a kernel trick for solving hard nonlinear problems. The approach presented, which is described as nonlinear transient computation, uses the dynamics of a well known chaotic attractor. The paper provides experimental results to show that this approach can be used to solve some challenging pattern recognition tasks. The paper also offers evidence to suggest that the efficacy of nonlinear transient computation for nonlinear pattern classification is dependent only on the generic properties of chaotic attractors and is not sensitive to the particular dynamics of specific sub-regions of chaotic phase space. If, as this work suggests, nonlinear transient computation is independent of the particulars of any given chaotic attractor, then it could be offered as a possible explanation of how the chaotic dynamics that have been observed in brain structures contribute to neural information processing tasks.Published here -
Crook N, 'Nonlinear Transient Computation'
Neurocomputing 70 (2006) pp.1167-1176
ISSN: 0925-2312Published here -
Crook N, Scheper TO, Pathirana V, 'Self-organised Dynamic Recognition States for Chaotic Neural Networks'
Information Sciences 150 (1-2) (2003) pp.59-75
ISSN: 0020-0255AbstractChaos offers several advantages to the Engineer over other non-chaotic dynamics. One is that chaotic systems are often significantly easier to control than other linear or non-linear systems, requiring only small, appropriately timed perturbations to constrain them within specific unstable periodic orbits (UPOs). Another is that chaotic attractors contain an infinite number of these UPOs. If individual UPOs can be made to represent specific internal states of a system, then a chaotic attractor can be turned into an infinite state machine. In this paper we investigate this possibility with respect to chaotic neural networks. We present a method by which a network can self-select UPOs in response to specific input values. These UPOs correspond to network recognition states for these input values.Published here -
Crook NT, olde Scheper T, Pathirana V, 'Self organised dynamic recognition states for chaotic neural networks'
Information Sciences 150 (1-2) (2003) pp.59-75
ISSN: 0020-0255AbstractChaos offers several advantages to the Engineer over other non-chaotic dynamics. One is that chaotic systems are often significantly easier to control than other linear or non-linear systems, requiring only small, appropriately timed perturbations to constrain them within specific unstable periodic orbits (UPOs). Another is that chaotic attractors contain an infinite number of these UPOs. If individual UPOs can be made to represent specific internal states of a system, then a chaotic attractor can be turned into an infinite state machine. In this paper we investigate this possibility with respect to chaotic neural networks. We present a method by which a network can self-select UPOs in response to specific input values. These UPOs correspond to network recognition states for these input values.Published here -
Crook NT, olde Scheper T, 'Adaptation based on memory dynamics in a chaotic neural network'
Cybernetics and Systems 33 (4) (2002) pp.341-378
ISSN: 0196-9722AbstractThe complex dynamics that emerge from systems governed by deterministic chaos offer significant advantages to the neuromorphic engineer. Included in these is the potential for a very large memory store and the ease with which chaotic systems can be controlled. By definition, a chaotic system is a periodic. However, during the course of its trajectory through state space, the chaotic system will come infinitely close to points that it has previously visited. These almost repeating trajectories are referred to as Unstable Periodic Orbits (UPOs). Normally, under the influence of chaos, the trajectory would move away exponentially fast from its previous path, thereby describing a new path on the surface of the attractor. It is possible to apply a simple delayed feedback control mechanism to a chaotic system that will constrain it within one of its UPOs. This article presents a neural implementation of this delayed feedback mechanism. The network presented here is able to stabilize different UPOs in response to different input signals, with each UPO corresponding to a dynamic recognition state for that input. We also present two learning rules for this network, which enables it to adapt to novel inputs in a self-organized manner.Published here -
Howes P, Crook N, 'Using Input Parameter Influences to Support the Decisions of Feedforward Neural Networks'
Neurocomputing 24 (1-3) (1999) pp.191-206
ISSN: 0925-2312Published here
Book chapters
-
Beton L, Hughes P, Barker S, Pilling M, Fuente L, Crook NT, 'Leader-Follower Strategies for Robot-Human Collaboration' in Aldinhas Ferreira MA, Silva Sequeira J, Osman Tokhi M, Kadar EE, Singh Virk G (ed.), A World with Robots, Springer (2017)
ISBN: 9783319466651 eISBN: 9783319466675AbstractThis paper considers the impact that robot collaboration strategies have on their human collaborators. In particular, we are interested in how robot leader/follower strategies affect perceived safety and perceived intelligence, which, we argue, are essential for establishing trust and enabling true collaboration between human and robot. We propose an experiment which will enable us to evaluate the impact of leader/follower collaboration strategies on perceived safety and intelligence.Published here -
Fuente LA, Lones MA, Crook NT, Olde Scheper TV, 'Harmonic versus chaos controlled oscillators in hexapedal locomotion' in Information Processing in Cells and Tissues, (2015)
AbstractPublished here Open Access on RADARThe behavioural diversity of chaotic oscillator can be controlled into periodic dynamics and used to model locomotion using central pattern generators. This paper shows how controlled chaotic oscillators may improve the adaptation of the robot locomotion behaviour to terrain uncertainties when compared to nonlinear harmonic oscillators. This is quantitatively assesses by the stability, changes of direction and steadiness of the robotic movements. Our results show that the controlled Wu oscillator promotes the emergence of adaptive locomotion when deterministic sensory feedback is used. They also suggest that the chaotic nature of chaos controlled oscillators increases the expressiveness of pattern generators to explore new locomotion gaits.
-
Crook N, Dobbyn C, olde Scheper T, 'Chaos as a Desirable Stable State of Artificial Neural Networks' in Advances in Soft Computing: Soft Computing Techniques and Applications, Physica-Verlag (2000)
Conference papers
-
Rolf M, Crook N, Steil J, 'From Social Interaction to Ethical AI: A Developmental Roadmap'
(2018)
eISSN: 2161-9484AbstractPublished here Open Access on RADARAI and robot ethics have recently gained a lot of attention because adaptive machines are increasingly involved in ethically sensitive scenarios and cause incidents of public outcry. Much of the debate has been focused on achieving highest moral standards in handling ethical dilemmas on which not even humans can agree, which indicates that the wrong questions are being asked. We suggest to address this ethics debate strictly through the lens of what behavior seems socially acceptable, rather than idealistically ethical. Learning such behavior puts the debate into the very heart of developmental robotics. This paper poses a roadmap of computational and experimental questions to address the development of socially acceptable machines. We emphasize the need for social reward mechanisms and learning architectures that integrate these while reaching beyond limitations of plain reinforcement learning agents. We suggest to use the metaphor of “needs” to bridge rewards and higher level abstractions such as goals for both communication and action generation in a social context. We then suggest a series of experimental questions and possible platforms and paradigms to guide future research in the area.
-
Barker S, Izadi H, Crook NT, Hayatleh K, Rolf M, Hughes P, Fellows N, 'Natural head movement for HRI with a muscular-skeletal head and neck robot'
(2017) pp.587-592
eISSN: 1944-9437 ISBN: 9781538635186AbstractThis paper presents a study of the movements of a humanoid head-and-neck robot called Eddie. Eddie has a musculo-skeletal structure similar to that found in human necks enabling it to perform head movements that are comparable with human head movements. This study compares the movements of Eddie with those of a more conventional robotic neck structure and with those of a human head. Results show that Eddie’s movements are perceived as significantly more natural and by trend more lifelike than the conventional head’s. No differences were found with respect to the impression of humanlikeness, consciousness, and elegance.Published here Open Access on RADAR -
Rolf M, Crook NT, 'What if: robots create novel goals? Ethics based on social value systems'
1668 (2016) pp.20-25
AbstractFuture personal robots might possess the capability to autonomously generate novel goals that exceed their initial programming as well as their past experience. We discuss the ethical challenges involved in such a scenario, ranging from the construction of ethics into such machines to the standard of ethics we could actually demand from such machines. We argue that we might have to accept those machines committing human-like ethical failures if they should ever reach human-level autonomy and intentionality. We base our discussion on recent ideas that novel goals could be originated from agents’ value system that express a subjective goodness of world or internal states. Novel goals could then be generated by extrapolating what future states would be good to achieve. Ethics could be built into such systems not just by simple utilitarian measures but also by constructing a value for the expected social acceptance of a the agent’s conduct.Published here Open Access on RADAR -
Barker S, Fuente L, Hayatleh K, Fellows N, Steil JJ, Crook N, 'Design of a Biologically Inspired Humanoid Neck'
(15820238) (2015) pp.25-30
ISBN: 978-1-4673-9674-5 eISBN: 978-1-4673-9675-2AbstractThis paper presents the design of a novel anthropomorphic robotic neck. It mimics the range of movements found in the human neck, actuated by pneumatic artificial muscles. The proposed humanoid neck simulates the anatomical functionality and structure of a human neck. Specifications are made according to biological, anatomical and behavioural data. The preliminary results show that the proposed humanoid neck is able to deliver the range of movements and head velocities comparable to those observed in human necks. These results also demonstrate that biologically inspired musculoskeletal robotic systems represent a reliable and robust platform to investigate motion development.Published here Open Access on RADAR -
Fuente LA, Ierardi H, Pilling M, Crook NT, 'Influence of Upper Body Pose Mirroring in Human-Robot Interaction'
9388 (2015) pp.214-223
eISBN: 978-3-319-25554-5AbstractThis paper explores the effect of upper body pose mirroring in human-robot interaction. A group of participants is used to evaluate how imitation by a robot affects people’s perception of their conversation with it. A set of twelve questions about the participants’ university experience serves as a backbone for the dialogue structure. In our experimental evaluation, the robot reacts in one of three ways to the human upper body pose: ignoring it, displaying its own upper body pose, and mirroring it. The manner in which the robot behaviour influences human appraisal is analysed using the standard Godspeed questionnaire. Our results show that robot body mirroring/non-mirroring influences the perceived humanness of the robot. The results also indicate that body pose mirroring is an important factor in facilitating rapport and empathy in human social interactions with robots.Published here -
Cheng MM, Warrell J, Lin WY, Zheng S, Vineet V, Crook N, 'Efficient salient region detection with soft image abstraction'
(2013) pp.1529-1536
ISBN: 9781479928408AbstractPublished here Open Access on RADARDetecting visually salient regions in images is one of the fundamental problems in computer vision. We propose a novel method to decompose an image into large scale perceptually homogeneous elements for efficient salient region detection, using a soft image abstraction representation. By considering both appearance similarity and spatial distribution of image pixels, the proposed representation abstracts out unnecessary image details, allowing the assignment of comparable saliency values across similar regions, and producing perceptually accurate salient region detection. We evaluate our salient region detection approach on the largest publicly available dataset with pixel accurate annotations. The experimental results show that the proposed method outperforms 18 alternate methods, reducing the mean absolute error by 25.2% compared to the previous best result, while being computationally more efficient.
-
Zhang Z, Sturgess P, Sengupta S, Crooke N, Torr P, 'Efficient discriminative learning of parametric nearest neighbor classifiers'
(2012) pp.2232-2239
Published here -
Sheasby G, Warrell J, Zhang Y, Crook N, Torr P, 'Simultaneous human segmentation, depth and pose estimation via dual decomposition'
(2012) pp.1-12
AbstractThe tasks of stereo matching, segmentation, and human pose estimation have been popular in computer vision in recent years, but attempts to combine the three tasks have so far resulted in compromises: either using infra-red cameras, or a greatly simplified body model. We propose a framework for estimating a detailed human skeleton in 3D from a stereo pair of images. Within this framework, we define an energy function that incorporates the relationship between the segmentation results, the pose estimation results, and the disparity space image. Specifically, we codify the assertions that foreground pixels should relate to some body part, should correspond to a continuous surface in the disparityspace image, and should be closer to the camera than the surrounding background pixels. Our energy function is NP-hard, however we show how to efficiently optimize a relaxation of it using dual decomposition. We show that applying this approach leads to improved results in all three tasks, and also introduce an extensive and challenging new dataset, which we use as a benchmark for evaluating 3D human pose estimation. -
Crook N, Goh WJ, Hawarat M, 'Pattern Recall in Networks of Chaotic Neurons'
BioSystems 87 (2007) pp.267-274
ISSN: 0303-2647 eISSN: 1872-8324Published here -
Crook NT, olde Scheper T, 'Adaptive Memory Dynamics in a Chaotic Neural Network'
33 (4) (2002) pp.131-
ISBN: 3-906454-32-0Published here -
Crook N, Scheper TO, 'An Adaptive Chaotic Neural Network'
(2002) pp.2580-2585
-
olde Scheper T, Crook NT, 'Delay Control Aspects of the Chaotic Rossler System'
(2002) pp.132-
ISBN: 3-906454-32-0Published here -
Crook NT, olde Scheper T, 'Learning in a Chaotic Neural Network'
(2002) pp.401-406
ISBN: 2-930307-02-1Published here -
Crook NT, olde Scheper T, 'A novel chaotic neural network architecture'
(2001) pp.295-300
ISBN: 2930307013 -
Crook N, Scheper TO, 'Dynamic Recognition States for Chaotic Neural Networks'
(2001) pp.62-72
Published here -
Crook N, Dobbyn C, Scheper TO, 'Chaos As a Desirable Stable State of Artificial Neural Networks'
(2000) pp.52-60
Other publications
-
Crook N, Scheper TO, 'Special Edition of Biosystems: Information Processing in Cells and Tissues', (2008)
Published here