414 research outputs found
Bimanual rope manipulation skill synthesis through context dependent correction policy learning from human demonstration
Learning from demonstration (LfD) provides a convenient means to equip robots
with dexterous skills when demonstration can be obtained in robot intrinsic
coordinates. However, the problem of compounding errors in long and complex
skills reduces its wide deployment. Since most such complex skills are composed
of smaller movements that are combined, considering the target skill as a
sequence of compact motor primitives seems reasonable. Here the problem that
needs to be tackled is to ensure that a motor primitive ends in a state that
allows the successful execution of the subsequent primitive. In this study, we
focus on this problem by proposing to learn an explicit correction policy when
the expected transition state between primitives is not achieved. The
correction policy is itself learned via behavior cloning by the use of a
state-of-the-art movement primitive learning architecture, Conditional Neural
Motor Primitives (CNMPs). The learned correction policy is then able to produce
diverse movement trajectories in a context dependent way. The advantage of the
proposed system over learning the complete task as a single action is shown
with a table-top setup in simulation, where an object has to be pushed through
a corridor in two steps. Then, the applicability of the proposed method to
bi-manual knotting in the real world is shown by equipping an upper-body
humanoid robot with the skill of making knots over a bar in 3D space. The
experiments show that the robot can perform successful knotting even when the
faced correction cases are not part of the human demonstration set
The Descriptive Challenges of Fiber Art
published or submitted for publicatio
Survey on model-based manipulation planning of deformable objects
A systematic overview on the subject of model-based manipulation planning of deformable objects is presented. Existing modelling techniques of volumetric, planar and linear deformable objects are described, emphasizing the different types of deformation. Planning strategies are categorized according to the type of manipulation goal: path planning, folding/unfolding, topology modifications and assembly. Most current contributions fit naturally into these categories, and thus the presented algorithms constitute an adequate basis for future developments.Preprin
Becoming Human with Humanoid
Nowadays, our expectations of robots have been significantly increases. The robot, which was initially only doing simple jobs, is now expected to be smarter and more dynamic. People want a robot that resembles a human (humanoid) has and has emotional intelligence that can perform action-reaction interactions. This book consists of two sections. The first section focuses on emotional intelligence, while the second section discusses the control of robotics. The contents of the book reveal the outcomes of research conducted by scholars in robotics fields to accommodate needs of society and industry
Data-driven robotic manipulation of cloth-like deformable objects : the present, challenges and future prospects
Manipulating cloth-like deformable objects (CDOs) is a long-standing problem in the robotics community. CDOs are flexible (non-rigid) objects that do not show a detectable level of compression strength while two points on the article are pushed towards each other and include objects such as ropes (1D), fabrics (2D) and bags (3D). In general, CDOs’ many degrees of freedom (DoF) introduce severe self-occlusion and complex state–action dynamics as significant obstacles to perception and manipulation systems. These challenges exacerbate existing issues of modern robotic control methods such as imitation learning (IL) and reinforcement learning (RL). This review focuses on the application details of data-driven control methods on four major task families in this domain: cloth shaping, knot tying/untying, dressing and bag manipulation. Furthermore, we identify specific inductive biases in these four domains that present challenges for more general IL and RL algorithms.Publisher PDFPeer reviewe
Robotics 2010
Without a doubt, robotics has made an incredible progress over the last decades. The vision of developing, designing and creating technical systems that help humans to achieve hard and complex tasks, has intelligently led to an incredible variety of solutions. There are barely technical fields that could exhibit more interdisciplinary interconnections like robotics. This fact is generated by highly complex challenges imposed by robotic systems, especially the requirement on intelligent and autonomous operation. This book tries to give an insight into the evolutionary process that takes place in robotics. It provides articles covering a wide range of this exciting area. The progress of technical challenges and concepts may illuminate the relationship between developments that seem to be completely different at first sight. The robotics remains an exciting scientific and engineering field. The community looks optimistically ahead and also looks forward for the future challenges and new development
Knowledge of knots: shapes in action
Logic is to natural language what knot theory is to natural knots. Logic is concerned with some cognitive performances; in particular, some natural language inferences are captured by various types of calculi (propositional, predicate, modal, deontic, quantum, probabilistic, etc.), which in turn may generate inferences that are arguably beyond natural logic abilities, or non-well synchronized therewith (eg. ex falso quodlibet, material implication). Mathematical knot theory accounts for some abilities - such as recognizing sameness or differences of some knots, and in turn generates a formalism for distinctions that common sense is blind to. Logic has proven useful in linguistics and in accounting for some aspects of reasoning, but which knotting performaces are there, over and beyond some intuitive discriminating abilities, that may require extensions or restrictions of the normative calculus of knots? Are they amenable to mathematical treatment? And what role is played in the game by mental representations? I shall draw from a corpus of techniques and practices to show to what extent compositionality, lexical and normative elements are present in natural knots, with the prospect of formally exploring an area of human competence that interfaces thought, perception and action in a complex fabric
In the weave: textile-based modes of making and the vocabulary of handcraft in selected contemporary artworks from South Africa
A thesis submitted in partial fulfillment of the requirements for the degree of
Doctor of Philosophy in Fine Art at the University of the Witwatersrand,
Johannesburg, South Africa
November 2017This research focuses on handcrafted artworks made by contemporary artists
working in South Africa who employ textile-based materials and processes of
fabrication related to weaving and/or unweaving in producing sculptural
objects, installations and performances. The primary aim is to investigate how
and to what ends contemporary artists working in South Africa have chosen to
engage in practices that are common to textile-based handcraft traditions of
weaving, stitching and tying. This is done with reference to indigenous southern
African textile-based traditions of making where appropriate. The focus is on
how artists have understood manual work and its philosophy, and how
conceptualization in their creative practice is accessed through the physical act
of repetitive making by hand, based particularly on those traditional textile craft
practices associated with weaving. In examining selected examples, such ‘textilic’
making practice is considered from a generative perspective involving a process
of ‘following materials’ through handcrafted fabrication (Ingold 2010a).
Furthermore, the study considers a material-conceptual interplay between ‘text,
textile and techne (craftsmanship)’ and the knowledge production that this
intertwining generates (Mitchell 2012). In South Africa, craft materials and
techniques are currently in use by contemporary artists in very particular ways,
and in relation to the historically politicized context of the country. I critically
examine how the selected artists’ works intersect with a politics of craft that is
particular to the country’s post-apartheid context, and how they subvert or
destabilize the hierarchical distinction between art and craft.MT 201
AR-MoCap: Using augmented reality to support motion capture acting
Technology is disrupting the way films involving visual effects are produced. Chroma-key, LED walls, motion capture (mocap), 3D visual storyboards, and simulcams are only a few examples of the many changes introduced in the cinema industry over the last years. Although these technologies are getting commonplace, they are presenting new, unexplored challenges to the actors. In particular, when mocap is used to record the actors’ movements with the aim of animating digital character models, an increase in the workload can be easily expected for people on stage. In fact, actors have to largely rely on their imagination to understand what the digitally created characters will be actually seeing and feeling. This paper focuses on this specific domain, and aims to demonstrate how Augmented Reality (AR) can be helpful for actors when shooting mocap scenes. To this purpose, we devised a system named AR-MoCap that can be used by actors for rehearsing the scene in AR on the real set before actually shooting it. Through an Optical See-Through Head- Mounted Display (OST-HMD), an actor can see, e.g., the digital characters of other actors wearing mocap suits overlapped in real- time to their bodies. Experimental results showed that, compared to the traditional approach based on physical props and other cues, the devised system can help the actors to position themselves and direct their gaze while shooting the scene, while also improving spatial and social presence, as well as perceived effectiveness
- …