Traditional vibration sensor of ship machinery using cable for power supply cannot meet the requirements of a large number of distributed sensors of the intelligent ship. A bouncing-ball based ...triboelectric nanogenerator (BB-TENG) to be used as a self-powered vibration frequency monitoring sensor is proposed. In the sensing test, the vibration frequency of 15 ∼ 50 Hz under different amplitudes can be measured accurately. The frequency calculation of the voltage signal can accurately reflect external vibration frequency, while the change of short-circuit current has linear relationship with the frequency, and the correlation coefficient is about 0.99. In addition, electrical signal test results and photos taken by high-speed cameras show that the limit of the available detection frequency of BB-TENG increases with the increase of amplitude and support height. The electrical output of BB-TENG under different working conditions are tested, which provides the basis for selecting suitable BB-TENG according to different vibration characteristics.
The transmission and control system is the core of the latest-twisting machine. For overcoming the shortcoming of the single-chip control system, which is used in the latest-twisting machine, a ...multi-motor transmission and control system of Latest-twisting machine based on PCI bus is developed. The transmission system is a multi-motor transmission system of four motors. An appropriate mathematic model has been developed based on multi-twisting theory. The running of spindles, the winding of bobbins and the reciprocate of guiding-yarns are controlled in phase by the control system, which is based on the integration of the AC servo technology, the frequency conversion technology, the PCI local bus technology and the twisting theory. The Visual Basic program language is used to realize modularized design in the software system. The dynamic-link library of the PCI board is called by the main program. The experiment results shows that the design of the transmission and control system can achieve the process objectives of twisting and winding of the latest twisting machine.
The key problem needed to be solved for digital textile printing technology lies in its low printing speed, which cannot meet the need of textile industry printing. For this problem, in this paper ...the processing tasks of host-side and device-side of control system are redistributed reasonably, and accordingly, a new direct printing data format is put forward, on the basis of which the inkjet printing data is processed by host-side controller, and the device-side controller directly receives the spraying signal. The features of the corresponding control system of the digital printing machine is analyzed here. By use of this method of task redistribution and the new direct printing data format, not only the printing speed can be increased, but also the control system of printing machine can be simplified, and thus it has important practical significance.
The spindle is an important component of two-for-one twisting machine. It gives the yarn twisting through high speed revolving. To solve the problems of resonance and noises, it is necessary to ...calculate frequency and analysis for spindle. With the establishment of math model, vibrating simulation is applied to natural frequency and vibration mode. It avoids the frequency of exciting force and natural frequency to be same or close. The finite element method studies the structure statics, the dynamics question effective method. It has some steps such as solid model establishment, restraint and load steps increasing, and modal analysis and so on. This method can accurately obtain the result high speed and become the structure mechanical analysis the powerful tool.
PCI-1240 is a 4-axis motion control card based on PCI bus. It is suitable for tube bender controlling system. To solve the problems of complexity in controlling and complicated operation in the ...conventional tube bender, a new multi-motor based on PCI-1240 is developed. With the establishment of the instruction code, a multi-motor driving mechanism and the controlling of reading bending data are applied in the new tube bender, which employs three servo motors. With the three mechanisms controlling, the machine structure is simplified. The tube quality is improved. The productivity is promoted. And mechanical-electrical integration level of the tube bender is enhanced.
In order to overcome the shortage in the traditional mechanical needle selecting machine of jacquard circle knitting machine, a new needle selecting machine based on piezoelectric ceramics is ...designed. This paper expands on the structure of needle selecting machine and its principle. The piezoelectric ceramics have a micro-displacement with the different flower type. The movement is enlarged by the needle piece and the needle moves to the requested location. Therefore, the three movements of needle selecting machine are realized such as the loop formation, loop accumutional and float adjustment loop.
To solve the problems of complexity in structure and huge time and energy consumption in operation for different twist yarn in the conventional mechanical twisting machine, a new multi-parameter ...driving system is developed. With the establishment of the math models of twisting, winding, and guiding-yarn, a multi-motor driving mechanism and the frequency communications technologies are applied in the new twisting machine, which employs two asynchronous motors and two servo motors. With the multi-parameter controlling, the machine structure is simplified. The yarn quality is improved. The productivity is promoted. And mechanical-electrical integration level of the twisting machine is enhanced.
A data acquisition system based on Advantech PCI-1710 is designed. PCI-1710 is used as the hardware platform of the system. The program is developed with Microsoft Visual Basic 6.0 by dint of ...Advantech 32 bit DLL drivers, drive and control of PCI-1710, which makes data acquisition, data transfer and data storage. The system has good commonality as well as extensibility and can be widely used in many dada acquisition areas.
The employment of energy-saving dispatching could reduce energy consumption and pollution emissions. The State Development and Reform Commission of China issued the policy of energy-saving generation ...dispatching, and it is expected that this dispatching scheme will be implemented in China soon. In this dispatching scheme, the ranking of generation dispatching will be based on the energy consumption and pollutant emission levels of different kinds of generation units, representing a significant change from the current dispatching practice in which each generation unit is allocated almost average utilization hours. Hence, the qualitative analysis of the impacts of this new dispatching scheme on the economical benefit of generation companies is a very important issue of extensive concern by itself. In this work, an effort is made to investigate the comprehensive impacts of the energy-saving dispatching scheme on generation companies. Simulations based on a sample example are employed for demonstration. Finally, some important problems to be studied are addressed from the viewpoint of generation companies.
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