Applied Mechanics and Materials Vols. 433-435

Abstract: Designed a Bluetooth-based wearable SAHS (sleep apnea hypopnea syndrome) monitoring device, the device can be real-time monitoring in the SAHS patient's respiratory state. Meanwhile, wearable technology achieves basic respiratory signal acquisition for low physiological and psychological load; Bluetooth achieves short-distance wireless transmission of respiration data and convenient communication with the handheld terminal such as PDA or smart phone, to ensure the continuous real-time monitoring of the patient.

Abstract: Shape memory alloy (SMA) has a property that when the temperature of SMA is stabilized, the fraction of Martensite phase keeps the same, and output force of SMA actuator also keeps constant. Based on that, a control strategy for set point force control of SMA actuators is proposed that during the process of driving, to stabilize output forces of SMA actuator, some voltages called balance voltages which can stabilize the temperature of SMA at the point will be input to SMA actuator. Besides, in order to shorten force rising times, before output force reaches the desired force, the max control voltage will be input to SMA actuator. Those balance voltages are related to output forces, therefore, its impossible to get all balance voltages. In this thesis, some balance voltages at different output forces are acquired by experiments. Based on this data, a series of fuzzy rules are used to fit the curve of all balance voltages. Since the balance voltages line is not accurate, balance voltages are needed to be slightly adjusted near the fitting curve according to force errors. Based on the control strategy, a fuzzy controller, with two input variables-desired force and force error and one output-control voltage, is designed. Finally, for testing the performance of the proposed controller, an experimental prototype is implemented. Experiment results show that the proposed controller is successfully applied to SMA actuator, and have a better control performance than conventional PI controller.

Abstract: The continuous development of the mechatronics technology provides important means for the mine electromechanical products to achieve safe, efficient and mechanized. First, mechatronics technology is introduced by this paper. Then the application of Mechatronics in the coal mine machinery are elaborated.

Abstract: Positioning control is widely used in many fields of applications, such as CNC machine tools, robotic motion control. This paper presents a novel method for position offset detection with a multi-switch type Hall sensors and a control design of tracking the moving object system based on PLC (programmable logic controller). The experimental results showed that the Hall switch sensor could follow the magnets in the different position without departing from each other when the rotating speed of the magnets is no more than 100 [rpm].

Abstract: In order to solve the air supply pressure instability problem in mine compressor, a fuzzy-PID controller is designed to be combined with conventional proportional-integral-derivative (PID) control and fuzzy control technology based on the programmable logic controller (PLC), where the compressor air supply system can achieve optimal control based on the system requirements and the actual usage, realizing air supply with constant pressure for compressor.

Abstract: The external rotor doubly salient permanent magnet (DSPM) generator with PM rotor tooth is designed. The two-dimensional model of the generator is analyzed by finite element method. Without changing the structure of generator, the magnet circuit is kept in the saturated state as soon as possible by paralleling capacitor besides the windings. By comparing the two kinds of rectifier topology structure, the results show that the average electromagnetic torque and the output voltage is significantly enhanced in series multiple rectifier circuit. The torque ripple of generator can be effectively suppressed in the case of load, which has a certain guiding significance for improving the output performance of the generator.

Abstract: The finite element method is adopted to simulate the vibration control effectiveness of autobody thin-walled structure by using the piezoelectric patches. The geometric parameters of thickness and area are chosen as the influence factors to analyze the control effectiveness of piezoelectric vibration control system. The simulation results show that the base metal thickness, piezoelectric patch thickness and the area of piezoelectric patch are main parameters and influence the control effectiveness obviously. The influence rules of these geometric parameters are obtained.

Abstract: The modern fuze technology puts forward higher and higher requirements of the fuze power, especially the fast feature of supplying power. Capacitor energy storage power whose energy is from the setter can supply power for fuze before launching the projectile, but its energy is little, so it couldnt satisfy the energy for the fuze work. The turbine alternator can generate power in all the trajectory, so its energy is enough, but it has the hysteresis characteristics of the start-up. This paper puts forward a composite power supply of using two kinds of power supply to solve the requirement of the fast feature of supplying power. Finally, the experiments demonstrate the composite power supply is feasible.

Abstract: Side discharging lorry is widely used for the transportation of coal and gravels in the coal mine and the highway tunnel. Automatic, safe and efficient tilting mechanism is a challenge for side discharging lorry. Driven by hydraulic cylinders, the tilting mechanism of conventional side discharging lorry needs an additional equipment to coordinate its action,which makes the side discharging lorry more complex and increases the cost. Based on conventional tilting mechanism, a novel tilting mechanism was proposed. The control mechanism, mainly consisted of several connecting rods, can achieving sequential motions of the tilting mechanism. With actual working condition, a mechanism analysis was done to simulate working procedure of the mechanism. The simulation demonstrates the feasibility of proposed mechanical structure for side discharging lorry.

Abstract: Researchers have successfully prepared reflection-mode hydrogen sensor by coating Palladium (Pd) alloy in the end of the fiber and it has been proved to be in good effect. Characteristics of the hydrogen sensors are influenced by several factors, such as thickness of thin film, substrate, light wavelength and the film material, etc. For best performance, an optical model of reflection-mode fiber hydrogen sensor is established. The effecting law of each factor is analyzed and discussed through model-based simulation method. The results can provide credible design methods for the reflection-mode fiber hydrogen sensor.