Ni nanowires (NWs) are driven in water using a rotating magnetic field. The NWs show various locomotion performances under different boundary conditions. Pure rotation occurs when the two ends of the NWs are homogenou...
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ISBN:
(纸本)9781424448326
Ni nanowires (NWs) are driven in water using a rotating magnetic field. The NWs show various locomotion performances under different boundary conditions. Pure rotation occurs when the two ends of the NWs are homogenously constrained. However, if the boundary conditions are different at the two ends of the NWs, tumbling motion, i.e., rotation plus translation, will be generated, which leads to the propulsion of NWs near a wall. These motions of NWs can be steered by the magnetic field. In addition, we present that the two NWs self-assemble to form a single NW with the magnetic field. The results imply that magnetic field is a promising approach for noncontact manipulation of Ni NWs or other 1-D ferromagnetic nanostructures at low Reynolds number aqueous environment in a controllable fashion.
The typical problems of the requirements elicitation stage increase when stakeholders are working on a Global software Development project. In order to fulfil the challenge of successfully carrying out the requirement...
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ISBN:
(纸本)9781424452583
The typical problems of the requirements elicitation stage increase when stakeholders are working on a Global software Development project. In order to fulfil the challenge of successfully carrying out the requirements elicitation process in a GSD environment, requirements specialists need suitable preparation. An improvement in this preparation necessitates an update of the contents, techniques and tools used in the teaching of the requirements elicitation process. In this paper we discuss these issues, show a list of knowledge and skills which are desirable for requirements elicitation engineers in GSD (obtained from a review of literature), and we also propose a simulator environment with which to develop certain skills that are appropriate for students and engineers in GSD requirements elicitation.
This paper describes an efficient method for retrieving the 3-dimensional shape associated to novelties in the environment of an autonomous robot, which is equipped with a laser range finder. First, changes are detect...
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This paper describes an efficient method for retrieving the 3-dimensional shape associated to novelties in the environment of an autonomous robot, which is equipped with a laser range finder. First, changes are detected over the point clouds using a combination of the Gaussian mixture model (GMM) and the earth mover's distance (EMD) algorithms. Next, the shape retrieval is achieved using two different algorithms. First, new samplings are generated from each Gaussian function, followed by a random sampling consensus (RANSAC) algorithm to retrieve geometric primitives. Furthermore, a new algorithm is developed to directly retrieve the shape according to the mathematical space of Gaussian mixture. In this paper, the set of geometric primitives has been limited to the set C = {sphere, cylinder, plane} . The two shape retrieval methods are compared in terms of computational cost and accuracy. Experimental results in various real and simulated scenarios demonstrate the feasibility of the approach.
Modes of melting and evaporation of metal at attogram level from individual carbon nanotubes (CNTs) are investigated experimentally using nanorobotic manipulation inside a transmission electron microscope. We compared...
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Modes of melting and evaporation of metal at attogram level from individual carbon nanotubes (CNTs) are investigated experimentally using nanorobotic manipulation inside a transmission electron microscope. We compared the melting and evaporation induced by electric current, Joule heating, charge, and ionization. Experiments show that the most effective method is by positively ionizing the encapsulated metal, therefore, an electrostatic field can be used to guide the flow. Applications and potential applications of mass transport and deposition in nanofluidic systems have been presented including self-welding, actuation, and storage.
Skid-steered mobile robots are widely used because of the simplicity of mechanism and high reliability. However, understanding of the kinematics and dynamics of such a robotic platform is challenging due to the comple...
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Skid-steered mobile robots are widely used because of the simplicity of mechanism and high reliability. However, understanding of the kinematics and dynamics of such a robotic platform is challenging due to the complex wheel/ground interactions and kinematic constraints. In this paper, we attempt to develop a kinematic and dynamic modeling scheme to analyze the skid-steered mobile robot. We model wheel/ground interaction and analyze the robot motion stability. As an application example, we present how to utilize the kinematic and dynamic modeling and analysis for robot localization and slip estimation using only low-cost strapdown inertial measurement units (IMU). The extended Kalman filter (EKF)-based localization scheme incorporates the kinematic constraints. The performance of the EKF-based localization and slip estimation scheme are presented. The estimation methodology is tested and validated on a robotic testbed.
This paper presents a motion planner for a vigilant humanoid robot. In this context of surveillance, the robot task is to keep a distinctive point in the environment in sight during all of its motion. The method we pr...
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ISBN:
(纸本)9781424445875
This paper presents a motion planner for a vigilant humanoid robot. In this context of surveillance, the robot task is to keep a distinctive point in the environment in sight during all of its motion. The method we propose consists of three main ingredients: (1) A motion planner for an appropriate simplified model of the walking robot, adapted to the particular needs of humanoid robots, that outputs an admissible path with local optimality properties. This path is guaranteed to satisfy the visibility constraints resulting both from the landmark and from the angular limits of the mechanical system; (2) A generic walking pattern generator that produces stable walking motions; (3) A generalized inverse-kinematics module to satisfy the remaining collisions and posture constraints, in particular the gaze direction. The effectiveness of this method is shown with several examples on the humanoid robot plataform HRP-2.
The run-time support mechanism usually deployed for monitoring the timing requirements of real-timesystems is based on deadline monitoring, i.e., the system calls specific application code whenever a deadline is viol...
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The recent video coding standard H.264/AVC show extremely higher coding efficiency compare to any other previous standards. H.264/AVC can achieve over 50% of bit rate saving with same quality using the rate-distortion...
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The recent video coding standard H.264/AVC show extremely higher coding efficiency compare to any other previous standards. H.264/AVC can achieve over 50% of bit rate saving with same quality using the rate-distortion process, but it brings high computational complexity. In this paper, we propose an algorithm that can reduce the complexity of the codec by reducing the block mode decision process adaptively. Block mode decision process in H.264/AVC consists of inter mode decision process and intra mode decision process. We deal with reduction method for inter and intra mode decision. In this paper an efficient method is proposed to reduce the inter mode decision complexity using the direct prediction methods based on block correlation and adaptive rate distortion cost threshold for early stopping. The fast intra mode reduction algorithm based on inter mode information is also proposed to reduce the computational complexity. The experimental results show that the proposed algorithm can achieve up to 63.34-77.39% speed up ratio with a little PSNR loss. Increment in bit requirement is also not much noticeable. (c) 2007 Elsevier Inc. All rights reserved.
Medical and medication devices are real-timesystems with safety and timing requirements. They range from hard-real-time, embedded, and reactive systems such as pacemakers to soft-real-time, standalone medication disp...
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Even if outdoor robotics is gaining increasing interest, universal systems are rare to find up to now. One of them is the autonomous mobile outdoor robot (AMOR), which operates in rough terrain under arbitrary weather...
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Even if outdoor robotics is gaining increasing interest, universal systems are rare to find up to now. One of them is the autonomous mobile outdoor robot (AMOR), which operates in rough terrain under arbitrary weather condition. This paper presents its software architecture and some performance figures. The whole system is designed by a modular and layered paradigm, to allow for easy reconfiguration and adaptation to new tasks. Elementary behaviours act as the fundament, which delivers the basic abilities and secures the robot. Model based components are utilized for more intelligent tasks like obstacle avoidance and local/global path planning. Robust operation in complex terrain is achieved by combining a multitude of sensors. The software architecture unifies them by introducing a virtualisation layer, which hides all hardware specific consideration from the application programmer. This way the overall system configuration can be easily adapted to the actual task without changing the high level software. Above the medium layer an object oriented system has been implemented, that is able to localise, navigate and avoid obstacles in rough terrain. The overall performance of the system has been proven by winning the first price in autonomous driving in the European Land Robot Trial (ELROB 2007) for urban and non-urban terrain. Details of the performance are given in the results.
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