26,788 research outputs found
Integrating Multiple 3D Views through Frame-of-reference Interaction
Frame-of-reference interaction consists of a unified set of 3D interaction techniques for exploratory navigation of large virtual spaces in nonimmersive environments. It is based on a conceptual framework that considers navigation from a cognitive perspective, as a way of facilitating changes in user attention from one reference frame to another, rather than from the mechanical perspective of moving a camera between different points of interest. All of our techniques link multiple frames of reference in some meaningful way. Some techniques link multiple windows within a zooming environment while others allow seamless changes of user focus between static objects, moving objects, and groups of moving objects. We present our techniques as they are implemented in GeoZui3D, a geographic visualization system for ocean data
Coaxial Atomic Force Microscope Tweezers
We demonstrate coaxial atomic force microscope (AFM) tweezers that can trap
and place small objects using dielectrophoresis (DEP). An attractive force is
generated at the tip of a coaxial AFM probe by applying a radio frequency
voltage between the center conductor and a grounded shield; the origin of the
force is found to be DEP by measuring the pull-off force vs. applied voltage.
We show that the coaxial AFM tweezers (CAT) can perform three dimensional
assembly by picking up a specified silica microsphere, imaging with the
microsphere at the end of the tip, and placing it at a target destination.Comment: 9 pages, 3 figures, in review at Applied Physics Letter
Would humans without language be apes?
The bedrock of comparative psychology of cognition, especially where nonhuman primates are concerned, rests on Darwin's famous account according to which continuity would be the main trait leading from the animal to the human mind. This idea was popularized through the statement in which Darwin postulated only quantitative differences between humans and the other species, namely "the difference in mind between man and the higher animals, great as it is, certainly is one of degree and not of kind" (Darwin, 1871, p. 128)..
Fast Object Learning and Dual-arm Coordination for Cluttered Stowing, Picking, and Packing
Robotic picking from cluttered bins is a demanding task, for which Amazon
Robotics holds challenges. The 2017 Amazon Robotics Challenge (ARC) required
stowing items into a storage system, picking specific items, and packing them
into boxes. In this paper, we describe the entry of team NimbRo Picking. Our
deep object perception pipeline can be quickly and efficiently adapted to new
items using a custom turntable capture system and transfer learning. It
produces high-quality item segments, on which grasp poses are found. A planning
component coordinates manipulation actions between two robot arms, minimizing
execution time. The system has been demonstrated successfully at ARC, where our
team reached second places in both the picking task and the final stow-and-pick
task. We also evaluate individual components.Comment: In: Proceedings of the International Conference on Robotics and
Automation (ICRA) 201
Particle assembly with synchronized acoustical tweezers
The contactless selective manipulation of individual objects at the
microscale is powerfully enabled by acoustical tweezers based on acoustical
vortices [Baudoin et al., Sci. Adv., 5:eaav1967 (2019)]. Nevertheless, the
ability to assemble multiple objects with these tweezers has not yet been
demonstrated yet and is critical for many applications, such as tissue
engineering or microrobotics. To achieve this goal, it is necessary to overcome
a major difficulty: the ring of high intensity ensuring particles trapping at
the core of the vortex beam is repulsive for particles located outside the
trap. This prevents the assembly of multiple objects. In this paper, we show
(in the Rayleigh limit and in 2D) that this problem can be overcome by trapping
the target objects at the core of two synchronized vortices. Indeed, in this
case, the destructive interference between neighboring vortices enables to
create an attractive path between the captured objects. The present work may
pioneer particles precise assembly and patterning with multi-tweezers
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