26,788 research outputs found

    Integrating Multiple 3D Views through Frame-of-reference Interaction

    Get PDF
    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

    Get PDF
    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?

    Get PDF
    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

    Full text link
    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

    Full text link
    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
    • …
    corecore