Applied Mechanics and Materials Vols. 556-562

Abstract: As the crawler vehicle with the excellent off-road performance, the battlefield survival ability, etc , are widely used in modern weapons systems In order to make teaching model close to the real equipment , designed a tracked vehicle of anti-aircraft gun based on the STM32F103 microcontroller, combined with the H-bridge motor circuit ,photoelectric encoder angle measurement and control principle of single lever operation, experimental results show that the tracked vehicle can complete forward, backward , turning and braking actions in accordance with the control command , with fast dynamic response , high control precision , to meet the design requirements.

Abstract: Because the parallel machine tool have high speed, high precision, high rigidity and the mechanical structure is simple, the parallel machine tool have been used in many field widely. In the research and application of parallel machine, the effect of processing parameter on machine processing is the most important problem. In the paper the improved artificial neural network is applied to the roughness prediction model of parallel machine tools, the model predict the roughness when the feed rate, spindle speed, processing angle and machining force are changed effectively.

Abstract: Friction wear testing machine is generally used in researches of various friction wear mechanisms, explorations of influences factors, and property evaluations of friction pair materials. Measurement accuracy and automation level of the friction wear testing machine directly influence the precision of data acquisition and analysis processing, as well as the intuition of data displaying. Based on virtual instrument LabVIEW, a data acquisition system of friction wear testing machine was developed. Hardware of this data acquisition system mainly consists of sensors utilized as acquiring information on rotate speed, normal pressure, friction force and temperature, as well as signal conditioning module and data acquisition card. Utilizing the LabVIEW, data processing and interface displaying software was programmed. Debugging results confirmed that the developed system can accurately acquire the demand information when operating the friction wear testing machine, also intuitively display these obtained information in real-time. Therefore, the developed data acquisition system satisfies the demand of precisely acquiring information related to friction wear testing of experimental materials.

Abstract: To research the radiation properties of heat flow around the aircrafts’ surface in hypersonic flight, a fusion algorithm to calculate the radiation of flow around hypersonic aircrafts is proposed in this paper. Firstly, the algorithm use the computational fluid dynamics (CFD) to calculate the basic aerodynamic parameters of the aircrafts which are inside boundary layer, such as pressure, density, etc. Subsequently, the model of the radiation of flow around aircrafts is built by using the engineering algorithm. Then, we can build the model of the radiation properties of heat flow around the surface of the aircrafts effectively. The result can reflect the distribution of the radiation of heat flow around surfaces of the aircrafts accurately, and provide data support to study its optical detection and thermal protection.

Abstract: The paper introduces the procedure of building model equation for thread rolling machine. Based on the model, show the machine has overshoot and takes minimal step method as the control algorithm. By the Simulink, prove the algorithm is correct for the machine.

Abstract: CAD/CAM system is one of the most widely used software in the field of mechanical design and manufacturing. The design of the mechanical parts generally uses CAD/CAM software, such as SolidWorks, Unigraphic, Pro/Engineer etc.. In this paper, by using UG software as a development platform, we use the software of UG/OPEN GRIP and UG MACRO as secondary development tool to realize the customization and development of general model of CAD/CAM system, and apply it in the design of professional free format machine parts. In the CAD/CAM system we put free format into parts manufacturing process and technology, and put forward the simple and effective process flow, so as to realize the optimization of CAD/CAM system. It provides the technical reference for the design and process of mechanical components.

Abstract: The traditional vehicle baking model can’t analyze the uncontrolled factors of the drivers at night due to moods fluctuation which cause large errors for estimation of the brake distance, thus the effective driving emergency braking reaction model can’t be built. This paper proposes an intelligent emergency braking reaction model under moods fluctuation which can analyze the drivers’ control features under different moods and build the relation models between the braking distance and driving speeds. The paper selects driving speeds, average road brightness and moods fluctuation as three indexes to calculate the best braking reaction speeds in order to control the emergency brake intelligently. The experiment illustrates the drivers’ braking reaction speeds and the stability can be greatly improved under the model with strong robustness.

Abstract: This paper presents a mathematical method to analyze the influence of each machine tool part deformation on the machining accuracy. Taking a 3-axis machine tool as an example, this paper divides the machine tool into the cutting tool sub-system and workpiece sub-system. Taking the deformation of lower surface of the machine bed as the research target, the mathematical model of the deformation on the displacement of the cutting point was established. In order to distribute the stiffness of each part, the contribution degree of each part on the machining accuracy was analyzed. Using this mathematical model, the stiffness of each part can be distributed at the design stage of the machine tool, and the machining accuracy of the machine tool can be improved economically.

Abstract: Wire of the brake pedal is not directly connected to the hydraulic environment in the braking By-wire system so the driver has no direct pedal feel. Then pedal simulator is an important part in the brake-by-wire system. A pedal force simulator was designed based on the traditional brake pedal curve of pedal force and pedal travel, AMESim and Matlab / Simulink were used as a platform to build simulation models and control algorithms. The simulation results show that the pedal stroke simulator and the control strategy meet the performance requirements of traditional braking system. It can be used in brake by wire system.

Abstract: Firstly, a new type of Movable Wedge – Ball Overrunning Clutch (MWBOC) with separable control part has been proposed in this paper. With the axial arranged and detachable structure, the clutch could adjust the self-locking components conveniently and its driven part could rotate freely to control part. The mentioned special structures make the clutch more universal, flexible and lower maintenance costs. Then, according to Hertz Contact Theory, the static structural design and stress check has been implemented. Finally, relying on simulation on the established dynamic model, it can be proved that: With the designed structural parameters, the newly-designed controllable overrunning clutch could realize the designed functions reliably, and the requirements for dynamic performance indexes could be met also. Project supported by National Natural Science Foundation of China (Grant No. : 61074104 )