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Epoxy is a polymeric material that is widely used in various fields as an adhesive, coating, and bulk material due to its outstanding properties. Many research studies on reinforced polymers have been conducted by adding micro/nanoparticles or fibers to attain better tribological properties. However, the tribological properties of patterning on the epoxy surface are relatively obscure. In this study, friction and wear properties of flat and V-groove patterned epoxy specimens were analyzed in dry and water lubricated sliding conditions to assess the effectiveness of the surface pattern in reducing friction and wear. It was found that under low applied force conditions in which the V grooves remained almost intact, the surface pattern contributed to decreasing the friction coefficient as much as 0.12 and increasing the stability of frictional behavior in dry sliding condition. This outcome was attributed to the ability of the grooves to trap wear debris inside the cavities. However, under water lubrication with polytetrafluoroethylene (PTFE) particles used as additives, the V-groove specimens were less effective in reducing friction due to the relatively small contact area. As the contact area increased, the effect of water lubrication with PTFE particles in reducing friction could be enhanced. These results are expected to serve as a fundamental basis for designing and fabricating the surface of polymeric components for tribological applications in dry and lubricated conditions.

With continuous improvement and update of embedded Linux kernel, embedded technology has been widely used in handheld devices and industrial control field. Therefore, a user-friendly graphical user interface (GUI) is essential for these applications. This paper firstly presents the design method for transplanting Qt on embedded platform of ARM9. Secondly it elaborates the device driver development and Qt interface development in Linux system with a Qt test program. All transplantation method of Qt and test program have been tested and verified on the ARM9 platform.

In this paper, 0.05 grade three-phase main control system of multi-station meter testing equipment (MTE) is presented. This design is based on the S3C2440 core board as the control core, and the software is based on Windows CE(WINCE) embedded operating system. The device is displayed and controlled by 7-inch Touch Screen. The main control system communicate with the error instrument and PC through Controller Area Network (CAN) bus, and the largest number of error instruments can connect to CAN bus is 100. The main control system communicates through RS232 bus with three-phase signal source and standard electric energy meter, through RS485 bus with programmable power amplifier. In this device, calibration of energy meters can not only through the PC software, but also use the main control system. Compared to the traditional design of the electric energy meter calibration device, the design’s the man-machine interface is more optimized, the number of electric energy meters can be test in the same time is more, faster communication, stronger anti-interference ability, and calibration is more efficiency.

This paper is about how to design an improved anti-ribboning method for the winder system. The system is based on the principle of a brushless DC motor control, which constantly changes relative velocity between the grooved drum and the yarn bobbin. This in turn, causes the changing of the winding ratio value. Therefore, it will accomplish the anti-ribboning control. Compared with the traditional anti-ribboning methods, the improved method can save more mechanical components and maintenance costs. Also, this method can develop different programs for different yarns. Therefore, this method is more efficient and versatile.

This paper analyzes the negative influence of dead-time,point out the shortcomings of traditional dead-time compensation methods , and then present a dead-time compensation method. Simulink simulation shows that the proposed method is effective. The proposed method is applied to a 15kW inverter which is controlled by STM32F103 MCU,and it can significantly reduce the THD value of the inverter output voltage waveform. The experiment proved that this method is simple and reliable, with good results.

In order to improve the step accuracy of two-phase hybrid stepping motors, this paper presents a high-performance stepping motor driver based on controllable dead-time compensation. After CPLD(Complex Programmable Logic Device) logical processing, the subdivision drive signal created by microcontroller STM32 becomes a complementary dead-time compensation drive signal which can realize precise control of stepper motor. The experiment shows that this program not only has effectively reduced the power consumption of the stepping motor, but also made whole system cost less.

In this paper, a gas stove and range hood integrated intelligent control system based on wireless communication is introduced. This system enables range hood running through wireless communication without human intervention, and gas stove can directly and automatically control the opening, the wind speed and closed of range hood. Compared to traditional gas stove and range hood, it implements the gas stove and range hood work together to make the operation more safe, convenient and fast. Through experimental test, the proposed design is feasible to achieve the gas stove and range hood integrated intelligent control system design requirements.

In this paper, a kind of variable frequency and multi-pressure water supply control system based on STM32 processor is designed. It can adjust the water pressure dynamically, according to the changes of water flow. Therefore, it can economize the energy consumption significantly. In order to improve real-time performance, the system adopts STs STM32F407 series processor which is based on ARM® CortexTM-M4 32-bit RISC core. It is used to collect the water flow, pressure and other data in real time, and automatically adjust the output frequency to control the motor speed, according to the set pressure value, and ultimately control the flow and pressure of the water supply system. According to the test, this variable frequency and multi-pressure water supply control system based on STM32 processor can meet the design requirements.

We have designed a photoelectric yarn signal acquisition system, which is based on the STM32 processor, having a sample rate up to 270kHz, and uploading data collection through synchronous parallel communication mode; Owing to the large noise of yarn signal and the unobviousness of yarn defect, we respectively adopting wiener filter and mean filter to filter this signal; The simulation result of matlab has manifested that both the wiener filter and mean filter can effectively decrease the noise level of the yarn signal and make the nep defects easier to identify, and that the wiener filter applies to application where the yarn speed is higher , while the mean filter is appropriate to the lower speed spinner.

In this paper, the application of a FPGA-based large-screen and high-resolution display accelerator technology in full-automatic textile machinery (computerized flat knitting machine) is studied. The design of traditional computerized knitting machine system is difficult to support the display of large screen and high resolution operating interface. Therefore, a displaying accelerator is designed in this paper. It comprises of FPGA, configuration chip, SDRAM and LVDS transmitter chip, is located between the embedded main processor and high resolution TFT LCD screen of computerized flat knitting machine, and implements the modules such as display acceleration logic and SDRAM controller relying on Verilog HDL programming in FPGA. The computerized flat knitting machine, applying displaying acceleration technology, can present its dynamic color interface on an 800 x 600 resolution TFT LCD (10.4") on the condition that real time, reliability and cost can be ensured.

In this paper, the merit and disadvantage of existing measurement methods for battery internal resistance are firstly analyzed. Then an online internal resistance measurement based on AC impedance method is proposed, which can increase the stability of the excitation source and enhance the performance of the filtered feedback signal. The method can be used to measure the small resistance of lithium-ion battery precisely. Experimental results show that the proposed method is accurate.

CPUs in embedded systems sometimes have limited performance for the sake of cost, so there may be impossible for these systems to drive a LCD display with a high frame rate. An FPGA based schema is proposed to increase the frame rate of the LCD display so that the texts etc. can be seen fluently. The frame rate enhancer is composed of three parts, an FPGA for receiving the data to be displayed, an SDRAM for data storage and an LCD controller for display control. The designed frame rate enhancer can be used in an embedded system, which has a large LCD display but a low performance CPU, without any flicker.

The batteries in a battery pack may have different internal resistances, and this inconsistency may lead to fast aging of the whole pack. In order to overcome the shortcomings of existing equalizing charge method, a bidirectional energy transfer mechanism based battery equalizing charge schema is given. We detailed analysis the working principle of equalization circuit and equalization work process, and the program analysis and argument by experiments. Experiments show that the method structure is simple, and it can quickly realize the dynamic transfer of energy between the batteries. The battery power charging imbalance can be effectively solved.

In this paper, the application of a FPGA-based large-screen and high-resolution display accelerator technology in full-automatic textile machinery (computerized flat knitting machine) is studied. The design of traditional computerized knitting machine system is difficult to support the display of large screen and high resolution operating interface. Therefore, a displaying accelerator is designed in this paper. It comprises of FPGA, configuration chip, SDRAM and LVDS transmitter chip, is located between the embedded main processor and high resolution TFT LCD screen of computerized flat knitting machine, and implements the modules such as display acceleration logic and SDRAM controller relying on Verilog HDL programming in FPGA. The computerized flat knitting machine, applying displaying acceleration technology, can present its dynamic color interface on an 800 x 600 resolution TFT LCD (10.4") on the condition that real time, reliability and cost can be ensured.

The technology of Needle selection is one of the key technology for computerized flat knitting machines. Proceed from the structure of the needle selection system, the working area for needle selector, pattern data, selecting needle slice instruction, this article researched the needle selection control system in detail. On condition that computerized flat knitting machines' working accuracy, stability, real-time, high efficiency is guaranteed, it put forward the test plan to the control logic of needle selection. This article provided a theoretical reference and practical significance for the computerized flat knitting machine's research and development.

Given the traditional use of sensors of temperature, humidity, smoke to identify the fire hazard, this design adds the image recognition algorithm based on OpenCV to identify fire through capturing images with camera, and caculates the probability of fire hazard according to weight of four factors that influence fire occurrence. The weight is determined by integrated multifactor probability model. Integrated fieldbus Redundancy technology is used in transmission of data on Ethernet and CAN. The practice has showed that the system achieved stability, high reliability, fast, and accuracy. The alarm is given rapidly when fire hazard happens.