Planning to Minimize the Human Muscular Effort during Forceful Human-Robot Collaboration

This work addresses the problem of planning a robot configuration and grasp to position a shared object during forceful human-robot collaboration, such as a puncturing or a cutting task. Particularly, our goal is to find a robot configuration that positions the jointly manipulated object such that the muscular effort of the human, operating on the same object, is minimized while also ensuring the stability of the interaction for the robot. This raises three challenges. First, we predict the human muscular effort given a human-robot combined kinematic configuration and the interaction forces of a task. To do this, we perform task-space to muscle-space mapping for two different musculoskeletal models of the human arm. Second, we predict the human body kinematic configuration given a robot configuration and the resulting object pose in the workspace. To do this, we assume that the human prefers the body configuration that minimizes the muscular effort. And third, we ensure that, under the forces applied by the human, the robot grasp on the object is stable and the robot joint torques are within limits. Addressing these three challenges, we build a planner that, given a forceful task description, can output the robot grasp on an object and the robot configuration to position the shared object in space. We quantitatively analyze the performance of the planner and the validity of our assumptions. We conduct experiments with human subjects to measure their kinematic configurations, muscular activity, and force output during collaborative puncturing and cutting tasks. The results illustrate the effectiveness of our planner in reducing the human muscular load. For instance, for the puncturing task, our planner is able to reduce muscular load by 69.5\% compared to a user-based selection of object poses.

La progression d’un objet partagé par une classe du primaire dans un environnement d’apprentissage en réseau en contexte d’éducation artistique

Résumé : Cet article traite du travail d’une classe du primaire qui a utilisé un espace numérique de collaboration (Knowledge Forum) pour la création d’un objet d’art lors d’un projet intitulé De jeunes artistes sans frontières. Nous avons observé l’évolution de la création de cet objet en analysant le discours de la classe qui l’a réalisé. Nos résultats montrent qu’en interagissant entre eux à l’écrit ou par la création d’une variété d’artéfacts, les élèves se sont engagés dans une démarche qui leur a permis de faire progresser leurs interactions de manière à créer un objet partagé. Ils ont aussi également utilisé un langage artistique propre à leur culture. Mots-clefs : Éducation artistique; environnement d’apprentissage en réseau; primaire; objet partagé. Abstract: An elementary class of the Remote Networked School initiative used Knowledge Forum for the creation of an art object during the Young Artists Without Borders projects. We observed the evolution of the creation of this object by analyzing the class’s discourse. Our results show that by interacting with each other in writing and/or by creating a variety of artifacts, students engaged in a process that allowed them to interact in a way to create a shared object. They also used an artistic language specific to their culture. Keywords: Arts Education; Networked Learning Environment; Primary; Shared Object.

Aristotle on the Unity of the Nutritive and Reproductive Functions

In De Anima 2.4, Aristotle claims that nutritive soul encompasses two distinct biological functions: nutrition and reproduction. We challenge a pervasive interpretation which posits ‘nutrients’ as the correlative object (antikeimenon) of the nutritive capacity. Instead, the shared object of nutrition and reproduction is that which is nourished and reproduced: the ensouled body, qua ensouled. Both functions aim at preserving this object, and thus at preserving the form, life, and being of the individual organism. In each case, we show how Aristotle’s detailed biological analysis supports this ontological argument.

Storytelling and stance-taking in group interaction

This paper looks at two highly prevalent actions in naturally-occurring talk: stance-taking and storytelling. Stance-taking and storytelling have been shown to co-occur often (e.g. Siromaa, 2012), and this is especially the case in reading group talk, a discursive environment in which speakers are engaged in the joint enterprise of assessing the meaning and quality of a shared object: a written narrative text (e.g. a novel). Insights from conversation analysis and dialogic syntax are used to analyse interactional data from several reading group meetings, with a focus on the types of storytelling that are found in this talk, the relationship between the various stories told in sequence in the talk – including the relationship between the written narrative text and the spoken narratives, and the ways in which stance-taking and storytelling are intertwined.

Building Academic Support in Preservice Teacher Education Using Peer Tutors: An Educational Action Research Project

In this paper, the authors report on the process of designing and implementing an academic support programme using peer tutors at a newly established rural university. The need for support for the development of first-year preservice student teachers' English language academic proficiency motivated the programme. In educational action research mode, the authors tracked changes and improvements to the programme and its implementation over a four-year period. Data in the form of questionnaires, interviews, video recorded lessons, and observations were generated in four cycles to inform reflections and new actions. The data were analysed using procedures associated with content analysis, and interpreted through the lens of cultural historical activity theory. The results show that competing tensions and a lack of focus on a shared object initially led to a delay in building shared knowledge in the beginning of the project. The authors interpret the results from a CHAT perspective and show the value of these tensions for identifying levers of change in a developmental process in the project. In this respect, the missteps of the researchers led to multiple iterations of reflection and action in order to arrive at a shared object, while defining the legitimacy of mediating tools, organisation of division of labour, and effective rules in a higher education programme.