495 research outputs found

    Real-Time Online Re-Planning for Grasping Under Clutter and Uncertainty

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    We consider the problem of grasping in clutter. While there have been motion planners developed to address this problem in recent years, these planners are mostly tailored for open-loop execution. Open-loop execution in this domain, however, is likely to fail, since it is not possible to model the dynamics of the multi-body multi-contact physical system with enough accuracy, neither is it reasonable to expect robots to know the exact physical properties of objects, such as frictional, inertial, and geometrical. Therefore, we propose an online re-planning approach for grasping through clutter. The main challenge is the long planning times this domain requires, which makes fast re-planning and fluent execution difficult to realize. In order to address this, we propose an easily parallelizable stochastic trajectory optimization based algorithm that generates a sequence of optimal controls. We show that by running this optimizer only for a small number of iterations, it is possible to perform real time re-planning cycles to achieve reactive manipulation under clutter and uncertainty.Comment: Published as a conference paper in IEEE Humanoids 201

    Relations between organizational commitment and demographic factors: a research in banking sector

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    Aim of this research is to answer if organizational commitment changes according to demografic factors. Inputs gained from 200 person sample group from banking sector. According to the analysis it is found that affective and continuance commitment increases with age and job experience, and all componenets of commitment increase according to time in the last job. With the results derived from analysis, research’s support to organizational theory is discussed and some advices put forward

    RNAi dependent epigenetic marks on a geminivirus promoter

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    Nicotiana benthamiana plants were stably transformed with an intron-spliced dsRNA producing construct cognate to bidirectional promoter of African cassava mosaic geminivirus (ACMV) DNA A. Transgenic lines expressed multiple siRNAs species upon ACMV infection. The de novo DNA methylation and an increased proportion of histone H3 Lysine-9 methylation (H3K9) at intergenic region (IGR) of ACMV DNA A were observed

    CASPR: Judiciously Using the Cloud for Wide-Area Packet Recovery

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    We revisit a classic networking problem -- how to recover from lost packets in the best-effort Internet. We propose CASPR, a system that judiciously leverages the cloud to recover from lost or delayed packets. CASPR supplements and protects best-effort connections by sending a small number of coded packets along the highly reliable but expensive cloud paths. When receivers detect packet loss, they recover packets with the help of the nearby data center, not the sender, thus providing quick and reliable packet recovery for latency-sensitive applications. Using a prototype implementation and its deployment on the public cloud and the PlanetLab testbed, we quantify the benefits of CASPR in providing fast, cost effective packet recovery. Using controlled experiments, we also explore how these benefits translate into improvements up and down the network stack

    Kaji Sistem Peralatan Penyerap Kalor pada Kotak Penyimpan Darah

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    This research aims to produce an effective heat sink with thermoelectric which is a semi conductor devices having several pairs of type P (positive) and N (negative) S content. Type P has a lower energy level while type N had a higher energy level. This tool, equipped with a heat sink as the heater, is mounted on a chamber to create a heat exchanger for a portable cooler box. Three types of thermoelectric modules were used with different fin types to find out the their effects on the temperature, T, and the rate of heat transfer, Q, inside the cooler box. The results shows that with the blood volume of 250 cc, the blood temperature can be decreased from 29 oC to 5.8 oC within 145 minutes. The ideal temperature for the blood storage ranges from 1 oC to 6 oC. Among the three types of fins that were tested, the most effective heat transfer was given by fin type no. 3, the cylindrical-shaped fins. The heat transfer obtained is 12.83 W/m2 oC. The lowest heat transfer was given by fin type no. 2, which is a slot type, with heat transfer rate of 3.85 W/m2 oC

    Non-Prehensile Manipulation in Clutter with Human-In-The-Loop

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    We propose a human-operator guided planning approach to pushing-based manipulation in clutter. Most recent approaches to manipulation in clutter employs randomized planning. The problem, however, remains a challenging one where the planning times are still in the order of tens of seconds or minutes, and the success rates are low for difficult instances of the problem. We build on these control-based randomized planning approaches, but we investigate using them in conjunction with human-operator input. In our framework, the human operator supplies a high-level plan, in the form of an ordered sequence of objects and their approximate goal positions. We present experiments in simulation and on a real robotic setup, where we compare the success rate and planning times of our human-in-the-loop approach with fully autonomous sampling-based planners. We show that with a minimal amount of human input, the low-level planner can solve the problem faster and with higher success rates
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