共查询到20条相似文献,搜索用时 31 毫秒
1.
目的提高包装机混合式定量的称重精度。方法针对包装机混合式定量称重系统具有非线性和时滞性的特点,构造三支路结构的双自由度数字控制器(RST控制器),等效为前向预测控制器和无延时控制器,以消除系统扰动和滞后的影响,设计基于RST的包装机定量称重控制系统。运用Simulink工具与传统PID控制器和PID-Smith控制器进行仿真对比。结果 RST控制器相较于PID控制器和PID-Smith控制器超调量小、调节时间短、跟踪能力好、鲁棒性强,能够有效地提高包装机称重控制系统的稳定性和控制精度。结论 RST控制器能够提高包装机混合式定量称重精度,从而提高包装机的包装精度。 相似文献
2.
基于PLC的定量称量包装控制系统设计 总被引:1,自引:1,他引:0
目的提高定量称量包装机的包装精度。方法在传统包装机械的基础上,基于PLC设计一种定量称量包装控制系统。结合RBF神经网络和PID控制方法,提出一种定量称量包装控制策略,以实现闭环控制。利用RBF神经网络的快速自学习能力调整PID控制的比例、积分、微分系数。以PLC为核心设计控制系统硬件结构并给出人机界面组成。结果通过多次实验,包装精度得到大幅提高,最大相对误差不超过0.6%。结论文中方法提高了定量称量包装机的精度、可靠性和可操作性。 相似文献
3.
General specifications are drawn up for methods of checking weighing machines for vehicles: automobiles,railroad wagons, and compound vehicles in motion, from which standards have been derived for methods of checking such weighing machines.Translated from Izmeritelnaya Tekhnika, No. 9, pp. 13–16, September, 2004. 相似文献
4.
5.
Material damages in fluid flow machines which are charged by cavitation cause costs due to service and downtime of the affected machines. Therefore the aim of engineering needs to be cutback of cavitation by the optimization of fluid flows and suitable selection of materials relating to cavitation. Cavitation has to be moved to temporally uncritical time ranges. This is why the cavitation resistance of materials and coatings that may be used to increase product durability need to be tested. In regard to extensive test series the adequacy of different evaluation methods like touch slice measurement, white light profilometry, weighing and optical comparison got tested in regard to suggest a suiting evaluation method for all possible applications. The results are showing that for evaluation of material tests the weighing method with a highly resolving scale suites best. In fact the use of white light profilometry is much better for accurate evaluation of coating tests. The optical comparison method supports quick comparisons of specimen in both cases. Broader research shows the impressive cavitation resistance of G‐CuAl8Mn8 compared to the probed steel specimen. 相似文献
6.
Conclusions When testing weighing machines by means of a piston loading device, the kinematic and dynamic characteristics of the machines differ from those encountered in practical service. Theoretical and experimental investigations have enabled us to establish relationships between the parameters of the testing apparatus such as will allow reliable testing to be carried out.Translated from Izmeritel'naya Tekhnika, No. 4, pp. 40–43, April, 1976. 相似文献
7.
针对目前粘性块状食品动态定量过程中,遇到的一些影响称重精度的问题,分别对机械结构、电路系统和软件算法进行了设计改进和方法研究.机械结构采用带搅拌机构的双管螺旋喂料机,以及带刮板的称斗结构,并在机械部件表面喷涂特氟龙涂料,减少粘结;硬件电路采用数字可编程放大器MAX4194作为称重传感器微弱电信号的放大器,采用32位单片微处理器LPC2134作为电路系统核心,可以对称重信号进行快速的处理;软件设计中,主程序采用分阶段称重,加入微分算法,以便于有效地滤除误差信号,并根据速度和重量对数据进行判断处理,对执行机构发送命令. 相似文献
8.
建立了铅酸蓄电池组的数学模型,采用对大容量铅酸蓄电池组进行突加扰动的试验方法,对不同容量的蓄电池组开展了实验研究,验证了所建模型并辨识出蓄电池组的参数。通过对不同状态的蓄电池组的参数辨识,发现其参数几乎不变。 相似文献
9.
10.
In this work a real automobile assembly line and the correspondent preassembly lines have been analyzed as a network of closed loops of machines decoupled by intermediate buffers. This work deals with some important aspects, which have still not been investigated in earlier literature, such as: machines processing pallets, which are not related to each other and depend on an external variable in a network with closed loops of machines and intermediate buffers, machines working at different cycle times in a network of closed loops of machines and intermediate buffers, machines working in both, stationary and transitory regime and the relationships between the cycle times of the machines in the stationary working regime in order to guarantee the production rate of the system. Finally how the transient results can be used to improve the performance of the system under certain working conditions is discussed. 相似文献
11.
This article considers a series manufacturing line composed of several machines separated by intermediate buffers of finite capacity. The goal is to find the optimal number of preventive maintenance actions performed on each machine, the optimal selection of machines and the optimal buffer allocation plan that minimize the total system cost, while providing the desired system throughput level. The mean times between failures of all machines are assumed to increase when applying periodic preventive maintenance. To estimate the production line throughput, a decomposition method is used. The decision variables in the formulated optimal design problem are buffer levels, types of machines and times between preventive maintenance actions. Three heuristic approaches are developed to solve the formulated combinatorial optimization problem. The first heuristic consists of a genetic algorithm, the second is based on the nonlinear threshold accepting metaheuristic and the third is an ant colony system. The proposed heuristics are compared and their efficiency is shown through several numerical examples. It is found that the nonlinear threshold accepting algorithm outperforms the genetic algorithm and ant colony system, while the genetic algorithm provides better results than the ant colony system for longer manufacturing lines. 相似文献
12.
A. J. Tew 《Quality and Reliability Engineering International》1987,3(1):3-13
Digital optical systems represent the current advance in submarine communications. Modern system designs require rapid evaluation of new components without relaxation of the stringent reliability requirements demanded for submarine applications. This article describes the development of integrated circuits (ICs) for submarine use. It goes on to show the design methodology, and discusses some limitations and the demanding reliability assurance aspects. The current IC designs are being used in both long-haul and short-haul links. The technology discussed is providing a major role in the future development of high-capacity optical submarine systems. 相似文献
13.
Muhammad Irfan Farman Ali Fazal Muhammad Saifur Rahman Ammar Armghan Yousaf Khan Faisal Althobiani Rehan Shafiq Mohammed Alshareef Mohammad E. Gommosani 《计算机、材料和连续体(英文)》2022,73(3):4885-4895
The fiber nonlinearity and phase noise (PN) are the focused impairments in the optical communication system, induced by high-capacity transmission and high laser input power. The channels include high-capacity transmissions that cannot be achieved at the end side without aliasing because of fiber nonlinearity and PN impairments. Thus, addressing of these distortions is the basic objective for the 5G mobile network. In this paper, the fiber nonlinearity and PN are investigated using the assembled methodology of millimeter-wave and radio over fiber (mmWave-RoF). The analytical model is designed in terms of outage probability for the proposed mmWave-RoF system. The performance of mmWave-RoF against fiber nonlinearity and PN is studied for input power, output power and length using peak to average power ratio (PAPR) and bit error rate (BER) measuring parameters. The simulation outcomes present that the impacts of fiber nonlinearity and PN can be balanced for a huge capacity mmWave-RoF model applying input power carefully. 相似文献
14.
Enormous efforts have been undertaken to develop rechargeable batteries with new electrode materials that not only have superior energy and power densities, but also are resistant to electrochemomechanical degradation despite huge volume changes. This review surveys recent progress in the experimental and modeling studies on the electrochemomechanical phenomena in high-capacity electrode materials for lithium-ion batteries. We highlight the integration of electrochemical and mechanical characterizations, in-situ transmission electron microscopy, multiscale modeling, and other techniques in understanding the strong mechanics-electrochemistry coupling during charge-discharge cycling. While anode materials for lithium ion batteries (LIBs) are the primary focus of this review, high-capacity electrode materials for sodium ion batteries (NIBs) are also briefly reviewed for comparison. Following the mechanistic studies, design strategies including nanostructuring, nanoporosity, surface coating, and compositing for mitigation of the electrochemomechanical degradation and promotion of self-healing of high-capacity electrodes are discussed. 相似文献
15.
Tahertalari Maryam Massoudi Abouzar Ji Xiaobo Javaheri M. Kalantarian M. M. 《Journal of Materials Science: Materials in Electronics》2022,33(5):2310-2321
Journal of Materials Science: Materials in Electronics - As a high-capacity cathode material with a considerable cycle life, lithium metal orthosilicates have attracted much attention. In this... 相似文献
16.
P. Komarek 《低温学》1976,16(3):131-142
Industrial applications of superconducting magnets are only feasible in the near future for superconducting homopolar machines and possibly MHD generators. In both cases there are no longer any major problems with the superconducting windings or cryogenic systems, but technological problems connected with other components are governing the chances of large scale applications.For superconducting synchronous machines, after the successful operation of machines in the MVA range, a new phase of basic investigations has started. Fundamental problems which could not be studied in the MVA machines, but which influence the design of large turbo-alternators, must now be investigated.Fusion power by magnetic confinement will probably be the largest field of application for superconducting magnets in the long run. The present research programmes require large superconducting magnets by the mid-1980s for the experimental reactors envisaged at that time.In addition to dc windings, pulse-operated superconducting windings are required in some systems, such as Tokamak. The high sensitivity of the overall plant efficiency and the active power demand of the pulsed windings require great efficiency from energy storage and transfer systems. Superconducting energy storage systems would be suitable for this, if transfer between inductances could be provided with sufficient efficiency. Basic experiments gave encouraging results.In power plant systems and electric machines an extremely high level of reliability and availability has been achieved. Less reliability will not be accepted for systems with superconducting magnets. This requires great efforts during the development work. 相似文献
17.
Journal of Materials Science: Materials in Electronics - Silicon is a promising high-capacity anode material for lithium ion batteries, but still suffers from the major issue of poor cyclability... 相似文献
18.
Wu Qili He Shiman Yang Xianfeng Yang Jingling Li Gaoren Meng Yuying Tong Shengfu Mai Liqiang Wu Mingmei 《Nano Research》2018,11(4):2116-2128
Nano Research - Nanostructured TiO2 has applications in solar cells, photocatalysts, and fast-charging, safe lithium ion batteries (LIBs). To meet the demand of high-capacity and high-rate LIBs... 相似文献
19.
测力称重计量的某些发展动向 总被引:2,自引:0,他引:2
本文从动态测量、自动在线测量及模型化测量三个方面,阐述了测力称重计量的某些近期发展动向.简要介绍了动态测力称重的特征及研究方法,叙述了自动在线测量的必要性及常见的自动秤,并指出模型化测量的意义及开发软件技术的重要性. 相似文献
20.
目的 针对面粉自动冲装称量生产加工要求,改进设计一种可实现多款称量功能的冲粉称量机构,并进行可变脉冲积分化控制设计,实现自动冲装称量应用.方法 采用可编程序控制器(PLC)的高速脉冲输出功能,设计分段高速脉冲控制驱动步进电机解决冲粉称量的生产控制要求,即在精确称量阶段通过设计匀速递减可变脉冲来快速无限逼近积分控制过程以达到精准称量.结果 该设计有效地抑制了称量中干扰和步进电机的高频振颤现象,最大过冲量小于3 g.结论 与传统的粉末自动冲装称量控制应用相比,该控制无整定参数且精准称量时间更短,设计更便于采用PLC编程来实现,称量精度更逼近称量传感器的分辨率. 相似文献