Development of a Semi-Autonomous Robotic System to Assist Children with Autism in Developing Visual Perspective Taking Skills

Robot-assisted therapy has been successfully used to help children with Autism Spectrum Condition (ASC) develop their social skills, but very often with the robot being fully controlled remotely by an adult operator. Although this method is reliable and allows the operator to conduct a therapy session in a customised child-centred manner, it increases the cognitive workload on the human operator since it requires them to divide their attention between the robot and the child to ensure that the robot is responding appropriately to the child's behaviour. In addition, a remote-controlled robot is not aware of the information regarding the interaction with children (e.g., body gesture and head pose, proximity etc) and consequently it does not have the ability to shape live HRIs. Further to this, a remote-controlled robot typically does not have the capacity to record this information and additional effort is required to analyse the interaction data. For these reasons, using a remote-controlled robot in robot-assisted therapy may be unsustainable for long-term interactions. To lighten the cognitive burden on the human operator and to provide a consistent therapeutic experience, it is essential to create some degrees of autonomy and enable the robot to perform some autonomous behaviours during interactions with children. Our previous research with the Kaspar robot either implemented a fully autonomous scenario involving pairs of children, which then lacked the often important input of the supervising adult, or, in most of our research, has used a remote control in the hand of the adult or the children to operate the robot. Alternatively, this paper provides an overview of the design and implementation of a robotic system called Sense- Think-Act which converts the remote-controlled scenarios of our humanoid robot into a semi-autonomous social agent with the capacity to play games autonomously (under human supervision) with children in the real-world school settings. The developed system has been implemented on the humanoid robot Kaspar and evaluated in a trial with four children with ASC at a local specialist secondary school in the UK where the data of 11 Child-Robot Interactions (CRIs) was collected. The results from this trial demonstrated that the system was successful in providing the robot with appropriate control signals to operate in a semi-autonomous manner without any latency, which supports autonomous CRIs, suggesting that the proposed architecture appears to have promising potential in supporting CRIs for real-world applications.Peer reviewe

The Iterative Development of the Humanoid Robot Kaspar: An Assistive Robot for Children with Autism

This paper gives an overview of the design and development of the humanoid robot Kaspar. Since the first Kaspar robot was developed in 2005, the robotic platform has undergone continuous development driven by the needs of users and technological advancements enabling the integration of new features. We discuss in detail the iterative development of Kaspar’s design and clearly explain the rational of each development, which has been based on the user requirements as well as our years of experience in robot assisted therapy for children with autism, particularly focusing on how the developments benefit the children we work with. Further to this, we discuss the role and benefits of robotic autonomy on both children and therapist along with the progress that we have made on the Kaspar robot’s autonomy towards achieving a semi-autonomous child-robot interaction in a real world setting.Peer reviewe

A Novel Reinforcement-Based Paradigm for Children to Teach the Humanoid Kaspar Robot

© The Author(s) 2019. This is the final published version of an article published in Psychological Research, licensed under a Creative Commons Attri-bution 4.0 International License. Available online at: https://doi.org/10.1007/s12369-019-00607-xThis paper presents a contribution to the active field of robotics research with the aim of supporting the development of social and collaborative skills of children with Autism Spectrum Disorders (ASD). We present a novel experiment where the classical roles are reversed: in this scenario the children are the teachers providing positive or negative reinforcement to the Kaspar robot in order for the robot to learn arbitrary associations between different toy names and the locations where they are positioned. The objective of this work is to develop games which help children with ASD develop collaborative skills and also provide them tangible example to understand that sometimes learning requires several repetitions. To facilitate this game we developed a reinforcement learning algorithm enabling Kaspar to verbally convey its level of uncertainty during the learning process, so as to better inform the children interacting with Kaspar the reasons behind the successes and failures made by the robot. Overall, 30 Typically Developing (TD) children aged between 7 and 8 (19 girls, 11 boys) and 6 children with ASD performed 22 sessions (16 for TD; 6 for ASD) of the experiment in groups, and managed to teach Kaspar all associations in 2 to 7 trials. During the course of study Kaspar only made rare unexpected associations (2 perseverative errors and 1 win-shift, within a total of 272 trials), primarily due to exploratory choices, and eventually reached minimal uncertainty. Thus the robot's behavior was clear and consistent for the children, who all expressed enthusiasm in the experiment.Peer reviewe

Development of a selection to recover improved DNA ligase enzymes during directed evolution

DNA ligases are essential enzymes used in many molecular biology applications. Of particular note, they are important enzymes in next generation sequencing (NGS) technologies. The improved speed, efficiency, and affordability of NGS over Sanger sequencing has greatly expanded the applications of DNA sequencing. In most NGS technologies ligase enzymes play a crucial role, for instance in ligating adaptors onto sequence fragments during sample preparation. This key step requires a blunt-ended ligation reaction, with highly efficient ligases required in order to create a sample library of high quality. The current go-to enzyme is T4 DNA ligase, which has not evolved in Nature to perform blunt ended ligations, and as such has relatively poor levels of activity when compared to other substrates. There is therefore potential to improve upon this enzyme and engineer a ligase that is more efficient with blunt-ended substrates. We have developed a novel function-based directed evolution selection to evolve blunt-ended ligases that have greater catalytic efficiency. The basis for this approach is the over-expression of a ligase enzyme variant which is then incubated with a linearised plasmid encoding for that same ligase variant. More efficient ligases will ligate the plasmid encoding for their own gene variant more efficiently (in a blunt-ended ligation), and so greater numbers of the circularised plasmid will be produced. Through successive rounds of transformation, amplification and ligation the most improved enzyme variants are enriched. This selection approach is being used to evaluate a panel of ligase variants in order to identify the best ligases for blunt-ended ligation applications. Please click Additional Files below to see the full abstract

The Viscous and Inviscid Strato-Rotational Instabilities

Using computational and analytical methods, we investigate the viscous and inviscid forms of the Strato-Rotational Instability (SRI) for the stratified Taylor-Couette system. We use an eigenfunction solver to find instability modes. We are able to vary the stratification, radius ratio η and rotation-rate ratio µ, and optimise the Reynolds number and relevant wavenumbers. We investigate the viscous and inviscid stability limits, extending the range of instability compared to prior results. Our results are consistent with the findings of Yavneh et al. [2001], Shalybkov and Rüdiger [2005], Le Bars and Le Gal [2007], Rüdiger and Shalybkov [2009], and Ibanez et al. [2016]. Building upon the results of Park and Billant [2013], we demonstrate that the µ < 1 inviscid system is unconditionally unstable if the buoyancy frequency is more than twice the inner cylinder rotation rate. For any given weaker stratification, we provide sufficient conditions for instability upon η and µ. We explore the structure of the SRI’s critical mode throughout the [η, µ]-parameter space, for fixed stratification. The considerable variation in structural appearance suggests that various instability mechanisms exist. We also find closed domain loops, for which the SRI becomes unstable for only a finite range of Reynolds numbers. This phenomenon is associated with a discontinuous change in the critical mode within the [η, µ]-parameter space. We find considerable differences between the viscous and inviscid systems, including a region of the parameter space which for weak stratifications is only unstable in the presence of viscosity. For the SRI to persist as a critical mode in the narrow-gap limit, we show that a near-solid-body-rotation limit is also necessary. This leads to the rotating stratified shear flow system described by Yavneh et al. [2001] for inviscid flows