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1.
This paper introduces hardware connections between computer and intellectualized instrument based on 89c51 sin-glechip .It gives the techniques to compile internet applications of Virtual Instruments with Delphi6.  相似文献   

2.
An online asymmetric trajectory generation method for biped robots is proposed to maintain dynamical postural stability and increase energy autonomy, based on the running stability criterion defined in phases. In a support phase, an asymmetric trajectories for the hip and swing leg of the biped robots is obtained from an approximated running model with two springless legs and a spring-loaded inverted pendulum model so that the zero moment point should exist inside the safety boundary of a supporting foot, and the supporting leg should absorb large reaction forces, take off and fly through the air. The biped robot is under-actuated with six degrees of under-actuation during flight. The trajectory generation strategies for the hip and both legs in a flight phase use the approximated running model and non-holonomic constraints based on the linear and angular momenta at the mass center. Next, we present an impedance control with a force modulation strategy to guarantee a stable landing on the ground and simultaneously track the desired trajectories where the desired impedance at the hip link and both legs is specified. A series of computer simulations for two different types of biped robots show that the proposed running trajectory and impedance control method satisfy the two conditions for running stability and make the biped robot more robust to variations in the desired running speed, gait transitions between walking and running, and parametric modeling errors. We have examined the feasibility of this method with running experiments on a 12-DOF biped robot without arms. The biped robot could run successfully with average forward speed of about 0.3359 [m/s]. Electronic Supplementary Material  The online version of this article () contains supplementary material, which is available to authorized users.
Jong Hyeon Park (Corresponding author)Email:
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3.
This paper presents a robot architecture with spatial cognition and navigation capabilities that captures some properties of the rat brain structures involved in learning and memory. This architecture relies on the integration of kinesthetic and visual information derived from artificial landmarks, as well as on Hebbian learning, to build a holistic topological-metric spatial representation during exploration, and employs reinforcement learning by means of an Actor-Critic architecture to enable learning and unlearning of goal locations. From a robotics perspective, this work can be placed in the gap between mapping and map exploitation currently existent in the SLAM literature. The exploitation of the cognitive map allows the robot to recognize places already visited and to find a target from any given departure location, thus enabling goal-directed navigation. From a biological perspective, this study aims at initiating a contribution to experimental neuroscience by providing the system as a tool to test with robots hypotheses concerned with the underlying mechanisms of rats’ spatial cognition. Results from different experiments with a mobile AIBO robot inspired on classical spatial tasks with rats are described, and a comparative analysis is provided in reference to the reversal task devised by O’Keefe in 1983.  相似文献   

4.
We hereby acknowledge that the published paper on our journal, “Balance recovery control for biped robot based on reaction null space method” by Baoping Wang, Renxi Hu, Jinming Zhang and Chuangfeng Huai, is a plagiarism of “Balance control of a humanoid robot based on the reaction null space method” by Akinori Nishio, Kentaro Takahashi and Dragomir N. Nenchev. We withdrew the plagiarized paper from the Springer website, and sent a formal notification letter to each author’s affiliation. Any submission from Baoping Wang, Renxi Hu, Jinming Zhang or Chuangfeng Huai will not be accepted in three years from now on. The above comment and this notification are published not only in this printed version, but also on the Springer website and our journal website. We have used plagiarism scanning software and started the online detection of plagiarism in the received papers in September 2010 for screening the plagiarized submission.  相似文献   

5.
Fault detection in autonomous robots based on fault injection and learning   总被引:1,自引:0,他引:1  
In this paper, we study a new approach to fault detection for autonomous robots. Our hypothesis is that hardware faults change the flow of sensory data and the actions performed by the control program. By detecting these changes, the presence of faults can be inferred. In order to test our hypothesis, we collect data from three different tasks performed by real robots. During a number of training runs, we record sensory data from the robots while they are operating normally and after a fault has been injected. We use back-propagation neural networks to synthesize fault detection components based on the data collected in the training runs. We evaluate the performance of the trained fault detectors in terms of number of false positives and time it takes to detect a fault. The results show that good fault detectors can be obtained. We extend the set of possible faults and go on to show that a single fault detector can be trained to detect several faults in both a robot’s sensors and actuators. We show that fault detectors can be synthesized that are robust to variations in the task, and we show how a fault detector can be trained to allow one robot to detect faults that occur in another robot.
Marco DorigoEmail:
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6.
In practice, the clearances of joints in a great number of mechanical systems are well under control. In these cases, some of the existing methods become unpractical because of the little differences in the order of magnitude between relative movements and computational errors. Assuming that the effects of impacts are negligible, we proved that both locations and forces of contacts in joints can be fully determined by parts of joint reaction forces. Based on this fact, a method particularly suited for multibody systems possessing frictional joints with tiny clearances is presented. In order to improve the efficiency of computation, recursive formulations are proposed based on the interactions between bodies. The proposed recursive formulations can improve the computation of joint reaction forces. With the methodology presented in this paper, not only the motion of bodies in a multibody system but also the details about the contacts in joints, such as forces of contacts and locations of contact points, can be obtained. Even with the assumption of impact free, the instants of possible impacts can be detected without relying upon any ambiguous parameters, as indicated by numerical examples in this paper.  相似文献   

7.
An increasing number of applications for dialogue systems presuppose an ability to deal appropriately with space. Dialogues with assistance systems, intelligent mobility devices and navigation systems all commonly involve the use of spatial language. For smooth interaction, this spatial language cannot be interpreted ‘in the abstract’—it must instead be related directly to a user’s physical location, orientation, goals and needs and be embedded appropriately in a system’s interaction. This is far from straightforward. The situated interpretation of natural language concerning space, spatial relationships and spatial activities represents an unsolved challenge at this time. Despite extensive work on spatial language involving many disciplines, there are no generally accepted accounts that provide support for the kind of flexible language use observed in real human-human spatial dialogues. In this paper, I review some recent approaches to the semantics for natural language expressions concerning space in order to motivate a two-level semantic-based approach to the interpretation of spatial language. This draws on a new combination of natural language processing and principles of ontological engineering and stands as a foundation for more sophisticated and natural dialogue system behavior where spatial information is involved.  相似文献   

8.
In this study, Reissner’s classical nonlinear rod formulation, as implemented by Simo and Vu-Quoc by means of the large rotation vector approach, is implemented into the framework of the absolute nodal coordinate formulation. The implementation is accomplished in the planar case accounting for coupled axial, bending, and shear deformation. By employing the virtual work of elastic forces similarly to Simo and Vu-Quoc in the absolute nodal coordinate formulation, the numerical results of the formulation are identical to those of the large rotation vector formulation. It is noteworthy, however, that the material definition in the absolute nodal coordinate formulation can differ from the material definition used in Reissner’s beam formulation. Based on an analytical eigenvalue analysis, it turns out that the high frequencies of cross section deformation modes in the absolute nodal coordinate formulation are only slightly higher than frequencies of common shear modes, which are present in the classical large rotation vector formulation of Simo and Vu-Quoc, as well. Thus, previous claims that the absolute nodal coordinate formulation is inefficient or would lead to ill-conditioned finite element matrices, as compared to classical approaches, could be refuted. In the introduced beam element, locking is prevented by means of reduced integration of certain parts of the elastic forces. Several classical large deformation static and dynamic examples as well as an eigenvalue analysis document the equivalence of classical nonlinear rod theories and the absolute nodal coordinate formulation for the case of appropriate material definitions. The results also agree highly with those computed in commercial finite element codes.  相似文献   

9.
Optimal and online preemptive scheduling on uniformly related machines   总被引:1,自引:0,他引:1  
We consider the problem of preemptive scheduling on uniformly related machines. We present a semi-online algorithm which, if the optimal makespan is given in advance, produces an optimal schedule. Using the standard doubling technique, this yields a 4-competitive deterministic and an e≈2.71-competitive randomized online algorithm. In addition, it matches the performance of the previously known algorithms for the offline case, with a considerably simpler proof. Finally, we study the performance of greedy heuristics for the same problem.  相似文献   

10.
A notable requirement of heterogeneous parallel and distributed computing systems is to maximize their processing performance and agreed upon QoS. Lots of work in this field has been done to optimize the system performance by improving certain metrics such as reliability, robustness, security, and so on. However, most of them assume that systems are running without interruption all the time and seldom consider the system’s intrinsic characteristics, such as failure rate, repair rate, and lifetime. In this paper, we study how to achieve high availability based on residual lifetime analysis for heterogeneous distributed computational systems with considering their essential features. First, we provide an availability model taking into account system’s expected residual lifetime. Second, we propose an objective function about the model and develop a heuristic scheduling algorithm to maximize the availability with the makespan constraint. At last, we demonstrate these advantages through the extensive simulated experiments.
Xin JiangEmail:
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11.
Dear Editor, I am coauthor of the paper entitled "Balance control of a humanoid robot based on the reaction null space method" by Akinori Nishio, Kentaro Takahashi and Dragomir N. Nenchev, published on pages 1996 - 2001 in the Proceeding of the 2006 IEEE/RSJ International Conference on Intelligent Robots and Systems held 9-15 October 2006 in Beijing, China.  相似文献   

12.
Energy saving is the crucial task of green architecture,energy-saving design and evaluation should be interactive.Low Energy Certificate(LEC),an interactive computer program for energy efficiency and certification of building envelope,is briefly introduced in this paper in aspects of certification standards,procedure,methods etc.Through the evaluation report of Innovation-pavilion PoI features,reference values of LEC are presented.  相似文献   

13.
We propose a discrete regularization framework on weighted graphs of arbitrary topology, which unifies local and nonlocal processing of images, meshes, and more generally discrete data. The approach considers the problem as a variational one, which consists in minimizing a weighted sum of two energy terms: a regularization one that uses the discrete p-Dirichlet form, and an approximation one. The proposed model is parametrized by the degree p of regularity, by the graph structure and by the weight function. The minimization solution leads to a family of simple linear and nonlinear processing methods. In particular, this family includes the exact expression or the discrete version of several neighborhood filters, such as the bilateral and the nonlocal means filter. In the context of images, local and nonlocal regularizations, based on the total variation models, are the continuous analog of the proposed model. Indirectly and naturally, it provides a discrete extension of these regularization methods for any discrete data or functions.  相似文献   

14.
Especially in a constrained virtual environment, precise control of foot placement during character locomotion is crucial to avoid collisions and to ensure a natural locomotion. In this paper, we present an extension of the step space: a novel technique for generating animations of a character walking over a set of desired foot steps in real time. We use an efficient greedy nearest-neighbor approach and warp the resulting animation so that it adheres to both spatial and temporal constraints. We will show that our technique can generate realistic locomotion animations over an input path very efficiently even though we impose many constraints on the animation. We also present a simple footstep planning technique that automatically plans regular stepping and sidestepping based on an input path with clearance information generated by a path planner.  相似文献   

15.
Tracing computations is a widely used methodology for program debugging. Lazy languages, however, pose new demands on tracing techniques because following the actual trace of a computation is generally useless. Typically, tracers for lazy languages rely on the construction of a redex trail, a graph that stores the reductions performed in a computation. While tracing provides a significant help for locating bugs, the task still remains complex. A well-known debugging technique for imperative programs is based on dynamic slicing, a method for finding the program statements that influence the computation of a value for a specific program input. In this work, we introduce a novel technique for dynamic slicing in first-order lazy functional languages. Rather than starting from scratch, our technique relies on (a slight extension of) redex trails. We provide a notion of dynamic slice and introduce a method to compute it from the redex trail of a computation. We also sketch the extension of our technique to deal with a functional logic language. A clear advantage of our proposal is that one can enhance existing tracers with slicing capabilities with a modest implementation effort, since the same data structure (the redex trail) can be used for both tracing and slicing.  相似文献   

16.
In order to construct 3D meshes from a single image quickly and intuitively, this paper presents a 3D reconstruction method based on control point grid. The key idea is to calculate the 2D control point grid of the target area and elevate each control point according to a parameterized 3D growing rule proposed from prior knowledge. First, the contour of the target object is divided into a major component and side components and the skeleton of each component is extracted. 2D control point grid is calculated combining the curvature and geometric feature of the contour and lifted into 3D space with corresponding height defined by parameter mapping. Finally, a complete 3D model is obtained after component combination and texturing. Experimental results show that this method can reasonably and efficiently recover the 3D shape of the target object while maintaining fine curvature and geometric features.  相似文献   

17.
An iterative algorithm is suited to reconstruct CT images from noisy or truncated projection data. However, as a disadvantage, the algorithm requires significant computational time. Although a parallel technique can be used to reduce the computational time, a large amount of communication overhead becomes an obstacle to its performance (Li et al. in J. X-Ray Sci. Technol. 13:1–10, 2005). To overcome this problem, we proposed an innovative parallel method based on the local iterative CT reconstruction algorithm (Wang et al. in Scanning 18:582–588, 1996 and IEEE Trans. Med. Imaging 15(5):657–664, 1996). The object to be reconstructed is partitioned into a number of subregions and assigned to different processing elements (PEs). Within each PE, local iterative reconstruction is performed to recover the subregion. Several numerical experiments were conducted on a high performance computing cluster. And the FORBILD head phantom (Lauritsch and Bruder ) was used as benchmark to measure the parallel performance. The experimental results showed that the proposed parallel algorithm significantly reduces the reconstruction time, hence achieving a high speedup and efficiency.
Jun NiEmail:
  相似文献   

18.
A multi-criteria feature selection method-sequential multi-criteria feature selection algorithm (SMCFS) has been proposed for the applications with high precision and low time cost. By combining the consistency and otherness of different evaluation criteria, the SMCFS adopts more than one evaluation criteria sequentially to improve the efficiency of feature selection. With one novel agent genetic algorithm (chain-like agent GA), the SMCFS can obtain high precision of feature selection and low time cost that is similar as filter method with single evaluation criterion. Several groups of experiments are carried out for comparison to demonstrate the performance of SMCFS. SMCFS is compared with different feature selection methods using three datasets from UCI database. The experimental results show that the SMCFS can get low time cost and high precision of feature selection, and is very suitable for this kind of applications of feature selection.  相似文献   

19.
As a newly discipline and methodology in the field of Artificial Intelligent, All Set Theory can be applied to describe macroscopic complex large systems and establish models in uncertain systems. The application of All Set Theory in controlling and decision-making for systems was discussed in the paper, furthermore, the Decision-making and Controlling System based on All Set Theory (AS-DCS) is put forward. At last, the model of AS-DCS and its structure as well as its program flow chart are presented.  相似文献   

20.
In this paper, we intend to show the basis of a general legged locomotion controller with the ability to integrate both posture and rhythmic motion controls and shift continuously from one control method to the other according to the walking speed. The rhythmic motion of each leg in the sagittal plane is generated by a single leg controller which controls the swing-to-stance and stance-to-swing phase transitions using respectively leg loading and unloading information. Since rolling motion induced by inverted pendulum motion during the two-legged stance phases results in the transfer of the load between the contralateral legs, leg loading/unloading involves posture information in the frontal plane. As a result of the phase modulations based on leg loading/unloading, rhythmic motion of each leg is achieved and inter-leg coordination (resulting in a gait) emerges, even without explicit coordination amongst the leg controllers, allowing to realize dynamic walking in the low- to medium-speed range. We show that the proposed method has resistance ability against lateral perturbations to some extent, but that an additional ascending coordination mechanism between ipsilateral legs is necessary to withstand perturbations decreasing the rolling motion amplitude. Even without stepping reflex using vestibular information, our control system, relying on phase modulations based on leg loading/unloading and the ascending coordination mechanism between ipsilateral legs, enables low speed dynamic walking on uneven terrain with long cyclic period, which was not realized in our former studies. Details of trajectory generation, movies of simulations and movies of preliminary experiments using a real robot are available at: http://robotics.mech.kit.ac.jp/kotetsu/.  相似文献   

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