Cherry-Picking with Reinforcement Learning : Robust Dynamic Grasping in Unstable Conditions

Grasping small objects surrounded by unstable or non-rigid material plays a crucial role in applications such as surgery, harvesting, construction, disaster recovery, and assisted feeding. This task is especially difficult when fine manipulation is required in the presence of sensor noise and perception errors; errors inevitably trigger dynamic motion, which is challenging to model precisely. Circumventing the difficulty to build accurate models for contacts and dynamics, data-driven methods like reinforcement learning (RL) can optimize task performance via trial and error, reducing the need for accurate models of contacts and dynamics. Applying RL methods to real robots, however, has been hindered by factors such as prohibitively high sample complexity or the high training infrastructure cost for providing resets on hardware. This work presents CherryBot, an RL system that uses chopsticks for fine manipulation that surpasses human reactiveness for some dynamic grasping tasks. By integrating imprecise simulators, suboptimal demonstrations and external state estimation, we study how to make a real-world robot learning system sample efficient and general while reducing the human effort required for supervision. Our system shows continual improvement through 30 minutes of real-world interaction: through reactive retry, it achieves an almost 100% success rate on the demanding task of using chopsticks to grasp small objects swinging in the air. We demonstrate the reactiveness, robustness and generalizability of CherryBot to varying object shapes and dynamics (e.g., external disturbances like wind and human perturbations). Videos are available at https://goodcherrybot.github.io/

Conceção, projeto e desenvolvimento de um dispositivo de auxílio à alimentação de indivíduos com deficiência

Dissertação de mestrado integrado em Engenharia BiomédicaA alimentação é uma atividade básica do dia-a-dia, mas existem pessoas que não se conseguem alimentar sozinhas, afetando a sua qualidade de vida, bem como a qualidade de vida dos que o rodeiam. Assim, com este projeto, pretende-se projetar e desenvolver um dispositivo de autoalimentação para estas pessoas. Após o levantamento dos dispositivos já existentes, foi estabelecida uma metodologia onde se definiram os objetivos, funções e especificações. Posteriormente, definiu-se a solução final através de várias soluções alternativas, onde este dispositivo final incorporará algumas características funcionais dos dispositivos de autoalimentação existentes no mercado, bem como apresentará uma utilização mais simples e prática. Por último, foram realizados testes de esforços e deformações a várias peças críticas, que verificam o bom funcionamento do dispositivo criado. De referir que todo o projeto foi realizado com o intuito de tornar o dispositivo desenvolvido o mais barato possível em comparação com os existentes no mercado, de forma a poder ser implementado em centros de dia, hospitais e casas particulares de modo economicamente viável.Feeding is a basic daily activity, but there are people who cannot feed themselves, affecting their quality of life, as well the quality of life of those around them. So, the goal with this project is to design and develop a self-feeding device for these people. After surveying the existing devices, a methodology was established where the objectives, functions and specifications were defined. Afterwards, the final solution was defined through several alternative solutions, where this final device will incorporate some functional characteristics of the existing self-feeding devices in the market, as well as present a simpler and more practical use. Finally, stress and strain tests were performed on several critical parts, which verify the proper functioning of the final device. It should be noted that the whole project was carried out with the intention of making the developed device as inexpensive as possible compared to those on the market, so that it can be implemented in day-care centres, hospitals, and private homes in an economically viable way

Kinematics and Robot Design II (KaRD2019) and III (KaRD2020)

This volume collects papers published in two Special Issues “Kinematics and Robot Design II, KaRD2019” (https://www.mdpi.com/journal/robotics/special_issues/KRD2019) and “Kinematics and Robot Design III, KaRD2020” (https://www.mdpi.com/journal/robotics/special_issues/KaRD2020), which are the second and third issues of the KaRD Special Issue series hosted by the open access journal robotics.The KaRD series is an open environment where researchers present their works and discuss all topics focused on the many aspects that involve kinematics in the design of robotic/automatic systems. It aims at being an established reference for researchers in the field as other serial international conferences/publications are. Even though the KaRD series publishes one Special Issue per year, all the received papers are peer-reviewed as soon as they are submitted and, if accepted, they are immediately published in MDPI Robotics. Kinematics is so intimately related to the design of robotic/automatic systems that the admitted topics of the KaRD series practically cover all the subjects normally present in well-established international conferences on “mechanisms and robotics”.KaRD2019 together with KaRD2020 received 22 papers and, after the peer-review process, accepted only 17 papers. The accepted papers cover problems related to theoretical/computational kinematics, to biomedical engineering and to other design/applicative aspects

March 1, 2004

The Breeze is the student newspaper of James Madison University in Harrisonburg, Virginia

Système autonome d’assistance au repas pour les personnes avec un handicap du haut du corps

RÉSUMÉ Pour les personnes souffrant de troubles de mobilité du haut du corps, des tâches quotidiennes qui semblent anodines peuvent devenir extrêmement complexes. La tâche d’alimentation en est un excellent exemple. Dans les 20 dernières années, une multitude de solutions à cette tâche ont été proposées par des laboratoires de recherche ou des entreprises afin d’assister ces personnes. Toutefois, la plupart de ces solutions ont d’importantes limitations : complexité d’installation et de transport, difficulté à contrôler, peu intuitif, etc. L’objectif de ce mémoire est de présenter une preuve de concept de solution abordable permettant à des personnes à mobilité réduite au niveau du haut du corps de s’alimenter plus aisément. La solution proposée inclut d’abord une caméra de stéréovision combinée à un système de reconnaissance d’objets basé sur l’apprentissage profond afin de repérer et localiser la nourriture dans une assiette située devant l’utilisateur. Cette partie permet à l’utilisateur d’éviter de se soucier de spécifier la position de la nourriture qu’il veut manger; le système le fait pour lui, ce qui rend le tout beaucoup plus intuitif et simple à contrôler. La caméra permet également d’établir un modèle de la scène et des obstacles présents, ce qui permet au système d’éviter ces obstacles. Les coordonnées de la nourriture à aller chercher sont ensuite envoyées au bras robotique MICO de Kinova, simulé avec ROS et Gazebo. Il s’agit d’un bras de réadaptation conçu pour être monté sur une chaise roulante, ce qui réduit la complexité d’installation et de transport. Un calcul de trajectoire est alors effectué et la cinématique inverse du bras robotique est calculée afin que le bras puisse approcher la nourriture avec l’effecteur choisi, une fourchette, selon un angle d’approche prédéfini. La nourriture est ensuite ramenée à une position fixe près de la bouche de l’utilisateur, le tout de manière entièrement autonome. En utilisant le système développé, l’utilisateur peut donc se nourrir de manière intuitive et autonome. Selon les tests effectués, le système constitue une preuve de concept valide, n’ayant échoué aucun des cinq essais effectués, et permet à l’utilisateur de manger deux morceaux de nourriture en un temps moyen de 90,22 secondes (dont 18,3% sont dédiés aux calculs). Le reste est donc entièrement utilisé pour le déplacement du bras, qui est une limitation physique du système robotique.----------ABSTRACT For people who suffer from upper-body disabilities, some casual tasks that seem innocuous can actually become extremely complex. Eating is an excellent example of such a task. In the last 20 years, multiple solutions have been suggested by academia and industries in order to help those people. However, most of these solutions have important limitations: complexity of installation or transport, control difficulty, lack of intuitiveness, etc. The goal of this thesis is to present a proof of concept of a low-cost solution that addresses this difficulty in carrying out the feeding task for people with disabilities. The suggested solution includes a stereovision camera combined with an object recognition system based on deep learning in order to detect and locate food on a plate in front of the user. This part of the system removes the need for the user to specify the exact position of the food he wants to eat; the robotic system does it for him or her, reducing significatively the complexity of the task and making it a lot more intuitive. The camera also allows the system to build a model of the scene, including obstacles, allowing the system to build a collision-free trajectory. The coordinates for the food to reach is then sent to the robot arm MICO by Kinova, which is simulated using ROS and Gazebo. This arm is specifically made to fit on wheelchairs, thus reducing the complexity of required installation and transport. The path planning is then completed and the inverse kinematics of the robot arm is computed in order to reach the food with the tool selected for the project, a fork, at a predefined angle of approach. The food is then brought back to a constant position near the user’s mouth. Everything is done autonomously. By using the developed system, the user can feed himself in an autonomous and intuitive manner. According to the tests, the system is a good proof of concept, having failed none of the 5 attempts, and allows the user to eat two pieces of food in an average time of 90.22 seconds (of which only 18.3% is dedicated to computations). The remaining 81.7% is thus used entirely for the movement of the robot arm, which is due to a physical limitation of the system

Between beeps: An autoethnographic study on Type 1 Diabetes, intersectionality and the body in chaos

This autoethnographic study examines Type 1 Diabetes through the lens of intersectionality framework, power and discipline, and the chaotic story of the body. As an Adult Type 1 Diabetic at diagnosis, I explore the tensions between my already established identities as an Asian American woman in academia attempting to incorporate and accept another identity, an identity of illness. This study utilizes sensory discourses and aesthetic arrangement of ten illness narratives to delve into my experience, placing the points of tension between my identities in conversation with my body’s silenced story of chaos as it undergoes acts of power and discipline. In teasing out my illness narratives, I invite the reader with me to sit with illness and to imagine the usually silenced affects as the muted body is engaged through self-reflection and interactions with others. Through the storied experience of my illness, I hope to evoke action in the form of reflection and mindful-action

AN ENACTIVE APPROACH TO TECHNOLOGICALLY MEDIATED LEARNING THROUGH PLAY

This thesis investigated the application of enactive principles to the design of classroom technolo- gies for young children’s learning through play. This study identified the attributes of an enactive pedagogy, in order to develop a design framework to accommodate enactive learning processes. From an enactive perspective, the learner is defined as an autonomous agent, capable of adapta- tion via the recursive consumption of self generated meaning within the constraints of a social and material world. Adaptation is the parallel development of mind and body that occurs through inter- action, which renders knowledge contingent on the environment from which it emerged. Parallel development means that action and perception in learning are as critical as thinking. An enactive approach to design therefore aspires to make the physical and social interaction with technology meaningful to the learning objective, rather than an aside to cognitive tasks. The design framework considered in detail the necessary affordances in terms of interaction, activity and context. In a further interpretation of enactive principles, this thesis recognised play and pretence as vehicles for designing and evaluating enactive learning and the embodied use of technology. In answering the research question, the interpreted framework was applied as a novel approach to designing and analysing children’s engagement with technology for learning, and worked towards a paradigm where interaction is part of the learning experience. The aspiration for the framework was to inform the design of interaction modalities to allow users’ to exercise the inherent mechanisms they have for making sense of the world. However, before making the claim to support enactive learning processes, there was a question as to whether technologically mediated realities were suitable environments to apply this framework. Given the emphasis on the physical world and action, it was the intention of the research and design activities to explore whether digital artefacts and spaces were an impoverished reality for enactive learning; or if digital objects and spaces could afford sufficient ’reality’ to be referents in social play behaviours. The project embedded in this research was tasked with creating deployable technologies that could be used in the classroom. Consequently, this framework was applied in practice, whereby the design practice and deployed technologies served as pragmatic tools to investigate the potential for interactive technologies in children’s physical, social and cognitive learning. To understand the context, underpin the design framework, and evaluate the impact of any techno- logical interventions in school life, the design practice was informed by ethnographic methodologies. The design process responded to cascading findings from phased research activities. The initial fieldwork located meaning making activities within the classroom, with a view to to re-appropriating situated and familiar practices. In the next stage of the design practice, this formative analysis determined the objectives of the participatory sessions, which in turn contributed to the creation of technologies suitable for an inquiry of enactive learning. The final technologies used standard school equipment with bespoke software, enabling children to engage with real time compositing and tracking applications installed in the classrooms’ role play spaces. The evaluation of the play space technologies in the wild revealed under certain conditions, there was evidence of embodied presence in the children’s social, physical and affective behaviour - illustrating how mediated realities can extend physical spaces. These findings suggest that the attention to meaningful interaction, a presence in the environment as a result of an active role, and a social presence - as outlined in the design framework - can lead to the emergence of observable enactive learning processes. As the design framework was applied, these principles could be examined and revised. Two notable examples of revisions to the design framework, in light of the applied practice, related to: (1) a key affordance for meaningful action to emerge required opportunities for direct and immediate engagement; and (2) a situated awareness of the self and other inhabitants in the mediated space required support across the spectrum of social interaction. The application of the design framework enabled this investigation to move beyond a theoretical discourse