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1.
The cutting room is currently the most highly automated part of the garment industry's manufacturing cycle. The next step, stripping the pieces from the cutting table and sorting them for assembly, is still highly labor intensive. At De Montfort University a robotic handling cell to perform the stripping operation has been developed and demonstrated  相似文献   

2.
A formal model based on Petri net transducers has been developed to specify the coordination and communication among the various task units in the CIRSSE platform system for robotic construction in space stations. The specification guarantees a mechanism of coherent control and communication for the effective cooperation among the different task units, and outlines the major steps toward the integration of the robotic platform system. The model is based on a coordination structure consisting of one dispatcher and three coordinators representing, respectively, the motion, vision, and gripper units of the platform system. The coordination structure insures some desired process properties for the system, such as boundedness, liveness, and reversibility, and easier translation from the formal specifications to the program codes based on Petri net transducer models. The model also assists with the system development in many ways, including (i) reducing the number of errors introduced while converting specifications to codes; (ii) assisting the developers in program implementation and verification (iii) allowing quicker adaptation to changed specifications; and (iv) allowing easier testing of the results for specification modifications. Therefore, it provides a useful tool for the design, simulation, performance evaluation, and implementation verification of the CIRSSE robotic platform system.  相似文献   

3.
瞬时蛋白-蛋白作用在细胞内有着重要的生理作用,所形成的界面为瞬时蛋白-蛋白界面.作为电子传递功能相关瞬时界面的代表,细胞色素P450被广泛的研究.本文选取具有高效电子传递效率的P450BM3蛋白作为研究素材,在其HEME域上选择了9个设计位点.通过在能量函数中引入特异性能量函数项,取得了较好的设计结果,有6个位点的残基类型与天然蛋白的残基类型一致.另外,本文还探讨了计算模型中加入水分子的重要性,说明了水分子在提供范德华能和氢键能方面的作用.  相似文献   

4.
Journal of Intelligent Manufacturing - In this paper, an automated layer defect detection system for construction 3D printing is proposed. Initially, a step-by-step procedure is implemented to...  相似文献   

5.
设计和构建了一个基于结构化对等网络的计算资源共享平台DHT-CRSP。它可以把因特网上用户提交的科学计算作业高效地映射到平台中合适的工作节点上运行,通过容错和安全机制,能保证系统的可靠性和正确性。描述了DHT-CRSP中支持的两种分布式哈希表:Chord协议节点树和CAN协议空间区域;分析了DHT-CRSP中高效的资源匹配算法。通过构建评测环境,运行各种负载与作业场景下的结果表明,DHT-CRSP系统可以获得好的负载均衡性能、低的资源匹配代价,它提供了一种构建高性能的桌面网格平台的新思路。  相似文献   

6.
目的:我们先前的体外肝微粒体抑制活性实验,已证实芹菜素和山萘酚对细胞色素CYP 1A2有较强的抑制作用。然而,其抑制机理仍然未知。分子模拟方法能更好了解这2个天然产物对1A2的抑制机理。方法:采用分子对接、分子动力学模拟及结合自由能计算的方法,研究它们对1A2的抑制作用。结果:芹菜素和山萘酚对1A2的预测结合自由能分别是-18.01和-16.40 kcal/mol,这与实验抑制活性结果一致。在1A2结合口袋中,残基呈平面性排列,与平面芹菜素和山萘酚存在紧密的范德华和疏水相互作用,因而小分子有较强的抑制作用。此外,活性位点残基也与小分子发生氢键和盐桥等相互作用,使小分子在结合口袋中的位置得到固定。  相似文献   

7.
In this study, we investigated the effect of genetic polymorphism on the three-dimensional (3D) conformation of cytochrome P450 1A2 (CYP1A2) using molecular dynamics (MD) simulations. CYP1A2, a major drug-metabolizing enzyme among cytochrome P450 enzymes (CYPs), is known to have many variant alleles. The genetic polymorphism of CYP1A2 may cause individual differences in the pharmacokinetics of medicines. By performing 100 ns or longer MD simulations, we investigated the influence of amino acid mutation on the 3D structures and the dynamic properties of proteins. The results show that the static structures were changed by the mutations of amino acid residues, not only near the mutated residues but also in distant portions of the proteins. Moreover, the mutation of only one amino acid was shown to change the structural flexibility of proteins, which may influence the substrate recognition and enzymatic activity. Our results clearly suggest that it is necessary to investigate the dynamic property as well as the static 3D structure for understanding the change of the enzymatic activity of mutant CYP1A2.  相似文献   

8.
Serum peptide profiling by MS is an emerging approach for disease diagnosis and biomarker discovery. A magnetic bead‐based method for off‐line serum peptide capture coupled to MALDI‐TOF‐MS has been recently introduced. However, the reagents are not available to the general scientific community. Here, we developed a protocol for serum peptide capture using novel magnetic C18 beads, and automated the procedure on a high‐throughput magnetic particle processor. We investigated bead equilibration, peptide binding and peptide elution conditions. The method is evaluated in terms of peaks counts and reproducibility of ion intensities in control serum. Overall, the DynaBead‐RPC18‐based serum sample processing protocol reported here is reproducible, robust and allows for the detection of ?200 peptides at m/z 800–4000 of serum that was allowed to clot for 1 h. The average intra‐experiment %CV of normalized ion intensities for crude serum and 0.5% TFA/0.15% n‐octyl glucoside‐treated serum, respectively, were 12% (range 2–38%) and 10% (3–21%) and the inter‐experiment %CVs were 24% (10–53%) and 31% (10–59%). Importantly, this method can be used for serum peptide profiling by anyone in possession of a MALDI‐TOF instrument. In conjunction with the KingFisher® 96, the whole serum peptide capture procedure is high‐throughput (?20 min per isolation of 96 samples in parallel), thereby facilitating large‐scale disease profiling studies.  相似文献   

9.
This paper presents the newly introduced class of (simple) kernel P systems ((s)kP systems) and investigates through a 3-colouring problem case study the expressive power and efficiency of kernel P systems. It describes two skP systems that model the problem and analyses them in terms of efficiency and complexity. The skP models prove to be more succinct (in terms of number of rules, objects, number of cells and execution steps) than the corresponding tissue P system, available in the literature, that solves the same problem, at the expense of a greater length of the rules.  相似文献   

10.
An uncalibrated, vision-guided robotic system, based on the method of camera-space manipulation, has been developed to reduce the time and cost associated with teaching a robot a suitable trajectory for plasma coating. The system achieves a high level of precision in both position and orientation control of a 6-DOF robotic arm  相似文献   

11.
12.
Mobile robots and smart environments are two areas of research that can easily profit from each other. Smart environments, which are spaces unobtrusively equipped with sensors and actuators, providing ambient services to the people living within. Mobile robots inside those smart environments can use the existing infrastructure to increase their performance while decreasing the cost of local sensor systems. On the other side, evaluation of ambient services is often a laborious task. This work presents an approach that simplifies the evaluation by making use of two frameworks from robotics to perform tests in simulated smart environments. A method based on the language as action principle is used to extract realistic behavior of people living in real-world smart environments. Using this data, many different scenarios with varying configurations (different floor layouts, numbers and types of sensors, different number of people and pets) can easily be simulated and the performance of the ambient services evaluated.  相似文献   

13.
At Los Alamos National Laboratory, a unique sample management robotic system has been developed that automates plutonium metal acid dissolutions, the aliquoting of resulting solutions to be analyzed using several analytical chemistry methods, and automates the barcode labeling of the solution containment vial providing positive solution identification. This system is based upon a commercial laboratory robot from Zymark, Inc. that has been enhanced by the addition of custom robotic workstations engineered and fabricated at our facility. This system will significantly reduce personnel radiation exposure and eliminate the redundancy of each analytical area producing separate dissolved plutonium solutions, which are used in chemical analyses.  相似文献   

14.
Automatic folding of cartons using a reconfigurable robotic system   总被引:3,自引:0,他引:3  
This paper proposes new theories and methodology for the study of folding carton and reconfigurable packaging systems and presents both virtual and experimental systems to support the theories. Equivalent mechanisms of cartons were established by describing carton creases as joints and carton panels as links. With the analysis of the equivalent mechanism, the gusset vertexes of cartons were analyzed based on their equivalent spherical linkages and were identified as guiding linkages that determine folding. A reconfigurable robotic system was developed to demonstrate the ability to erect diverted cartons in the reconfigurable packaging system which could previously only be achieved manually.  相似文献   

15.
The direct electrochemistry of house fly cytochrome P4506A1 (CYP6A1) confined in dioctadecyl dimethyl ammonium bromide (DDAB) film was achieved. The immobilized CYP6A1 displayed a pair of redox peaks with a formal potential of −0.36 mV in pH 7.0 O2-free phosphate buffers at scan rate of 1 V s−1 and the direct electron transfer of CYP6A1 was characterized by voltammetry. The CYP6A1 in the DDAB film retained its bioactivity and could catalyze the reduction of dissolved oxygen. Upon addition of its substrate aldrin or heptachlor to the air-saturated solution, the reduction peak current of dissolved oxygen increased, which indicates the catalytic behavior of CYP6A1 to its substrates. By amperometry a calibration linear range was obtained to be 9.08 × 10−6-4.54 × 10−5 mol L−1 with a sensitivity of 80 μA mM−1 for aldrin or 8.91 × 10−6-4.46 × 10−5 mol L−1 with a sensitivity of 66 μA mM−1 for heptachlor. The apparent Michaelis-Menten constant for the electrocatalytic activity of CYP6A1 was found to be 7.468 × 10−5 mol L−1 for aldrin and 4.316 × 10−5 mol L−1 for heptachlor. The bioelectrocatalytic products were analysed using gas chromatography (GC) and electron ionization-mass spectrometry (EI-MS). The results confirmed that epoxidation was the main pathways of CYP6A1-mediated organochlorine pesticides oxidation.  相似文献   

16.
This paper presents a novel actuation mechanism to enable the span-wise undulating motion of the caudal fin of a robotic fish. To minimize the mechanical components such as cams, pulleys and gears, a flexible joint-based wave machine mechanism is adopted to generate the waving motion of the caudal fin. In particular, the proposed mechanism has the advantages of minimum total weight and few mechanical components because of its simplicity. Through analysis and experiments, the efficacy of the proposed mechanism is validated.  相似文献   

17.
Seventy cases of computed tomography (CT) data were selected from The Cancer Imaging Archive to aid in the design of a magnetically-guided capsule endoscope platform. According to the distance between the large bowel and the abdomen skin measured on CT images, the supine position showed the advantage in reducing the distance between internal and external magnets; thus, we used the supine position as the detection posture for magnetically-guided capsule colonoscopy. From the selected 70 cases of CT data, we chose 30 supine cases with different waistline lengths to extract the centerline of the large bowel as the motion trajectory of the capsule. We analyzed these trajectories to define the workspace of the capsule and simulated the motion of the capsule inside the large bowel. The distance between the large bowel and the abdomen surface, which can be regarded as the minimum distance of the internal and external magnets, was calculated and used as the reference for designing the magnet. Based on the abdomen volume and the workspace of the capsule, we provided a minimum workspace of the external magnet and designed an auxiliary degree of freedom for the manipulator to control the capsule to pass through the large bowel.  相似文献   

18.
This paper presents a backstepping control method using radial‐basis‐function neural network (RBFNN) for improving trajectory tracking performance of a robotic helicopter. Many well‐known nonlinear controllers for robotic helicopters have been constructed based on the approximate dynamic model in which the coupling effect is neglected; their qualitative behavior must be further analyzed to ensure that the unmodeled dynamics do not destroy the stability of the closed‐loop system. In order to improve the controller design process, the proposed controller is developed based on the complete dynamic model of robotic helicopters by using an RBFNN function approximation to the neglected dynamic uncertainties, and then proving that all the trajectory tracking error variables are globally ultimately bounded and converge to a neighborhood of the origin. The merits of the proposal controller are exemplified by four numerical simulations, showing that the proposed controller outperforms a well‐known controller in (J. Robust Nonlinear Control 2004; 14 (12):1035–1059). Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

19.
《Advanced Robotics》2013,27(3):247-267
We conducted a micro-gravity flight experiment on a space robotic arm, which is a part of the Reconfigurable Brachiating space Robot (RBR) unit arm developed by the authors. We used a 4-d.o.f. arm and an end-effector in the experiment. The airplane (MU-300) generates the micro-gravity environment for approximately 20 s in parabolic flight operation. After the flight, we conducted the corresponding ground experiments, and obtained the data of the motor current, servo control characteristics and manipulation performances, which were compared with the flight experiment data. Then, we conducted the numerical analysis of the 4-d.o.f. RBR arm based on the experiment results. In the analysis, we investigated feasibility of simulation model and identified model parameters. In this paper, we report the results of the flight experiments and numerical analysis.  相似文献   

20.
The paper presents the identification issues of the self-tuning nonlinear controller ASPECT (Advanced control algorithmS for ProgrammablE logiC conTrollers). The controller is implemented on a simple PLC platform with an extra mathematical coprocessor, but is intended for the advanced control of complex processes. The model of the controlled plant is obtained by means of experimental modelling. A special batch-wise algorithm that is based on the Takagi–Sugeno model and uses “fuzzy instrumental variables” technique is described in the paper. Many robustness problems of the classical adaptive approaches can be circumvented to some extent by the proposed batch-wise approach combined with a supervisory mechanism. The paper also includes some experimental results on the hydraulic pilot plant and some simulation case studies.  相似文献   

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