Abstract: A kind of multiple parameter data acquisition system was designed based on single-chip microcomputer which can realized the data acquisition of temperature and DC motor speed. The data acquisition system consists of sensor, signal processing circuit, single-chip microcomputer and LED digital tube. The speed signal is acquired by photoelectric sensor, put into the Single-chip microcomputer processed after processed by signal processing circuit, and displayed the value in the digital tubes. The temperature signal is acquired by digital sensor, and the Single-chip microcomputer can read the data directly. Through two independent keyboards, the test system realized the data acquisition and data switch displaying of the multiple parameters.
Abstract: Computational Fluid Dynamics (CFD) is used for the investigation of the aerodynamic characteristics of the truck. The gap between the truck and the container of the heavy truck on its aerodynamic characteristics were simulated by using equations and dynamic mesh method. The finite volume method is used to discrete the governing equations, the second-order up wind difference scheme is adopted for the convection term and the centric difference scheme for the dissipation term. The discretion of time is carried out by a full-implicit time integral scheme. Analysis of the simulated flow fields and the change pattern of the aerodynamic drag under different gap length demonstrate that when the gap length change and the aerodynamic characteristics change. This paper provides a theoretical reference for the development of truck products determining the gap distance between the truck and the container.
Abstract: A special vehicle frame as the research object, its topology optimization mathematical model and its algorithm is established based on variable density method. Topology optimization method of continuum structures is applied to the frame structural design of this special vehicle using Optistruct solver. Take the least flexibility of frame as design goal; topology optimization design of frame structure was carried under the condition of flexure, torsion and flexure-torsion. New structural model of frame was determined according to results of topology optimization and engineering experience. The calculation of the stress, deformation and the volume for optimization results was conducted with ANSYS software, and compared with the data before optimization. The results showed that the safety performance of optimized frame improved, and the weight reduced.
Abstract: An optimization on Thin-walled Curved Surface Part (TCSP) position is proposed in order to meet the increasing flexibility need of airplane, automobile industry etc. The position process comes down to coordinate transformation problem. A method based on Oriented Bounding Box (OBB) iteration for TCSP position in array-type fixture is proposed to solve parameters of part coordinate transformation matrix, and comparisons between OBB and OBB iteration is shown. The calculation example shows that the proposed method is feasible, and can effectively solve position parameters of the TCSP position process.
Abstract: The integral axle housing of a special vehicle was taken as the research object, with the 3D model of the drive axle housing built by using 3D CAD software UG. The ANSYS is taken as the FEA computing platform, the strength and stiffness of the axle housing under the five load conditions is calculated by it. The results show that the impact of such conditions, the drive axle housing can happen to be yield easily. While in the remaining conditions, the drive axle housing is not too much security reserves, which exit some certain security risks. The method used in this paper for great guiding significance to reduce product development costs, shorten development cycles and improve product quality.
Abstract: In this paper the basic structure of frame is optimized through homogenization method in the basic frame structure loaded with bending conditions under the conditions that ANSYS is regarded as the optimal design platform, the flexibility of frame is taken as the objective function and the volume is used as a constraint The optimization topology structure of the frame is obtained which meets the volume constraints and total compliance smallest. Using the ANSYS software calculates and verifies the security of frame structural strength under the fully loaded bending condition. Model and optimization methods used in this paper also can apply to other types of optimization design of the frame, and provides a useful reference for the optimized design of the similar structure.
Abstract: The locomotive coupling came from the development of heavy-haul transportation in railway. Considering the insufficiencies of cable and radio in locomotive coupling at present, a new method of locomotive coupling is presented in this paper. The overall design of system scheme is provided based on WLAN. The system feasibility is analyzed and verified by using OPNET Modeler. The hardware structure of coupling transmission device and development process of embedded operating system are described briefly. Finally, taking measures guarantees the system reliability of data transmission.
Abstract: The aim of this study is to evaluate the blood compatibility of disposable burette transfusion apparatus and provide the basis for the clinical safety of medical products. Whole blood clotting time (WBCT), prothrombin time(PT),partial prothrombin time(PTT), hemolytic rate and bacterial endotoxin were measured. The results showed that there was no significant difference between the samples and the negative control on indexes of WBCT, PT and PTT (p>0.05), hemolysis test showed that the hemolysis rate of the sample was 1.38% (less than 5%), which was coincident with the criteria of the medical devices. Endotoxin levels were lower than 0. 5 EU/ml. All of the results above suggested that the disposable burette transfusion apparatus had a good blood compatibility and no pyrogen.
Abstract: In order to research the fatigue life characteristics of the pivotal load carrying structure equalizing beam of a heavy-duty truck, a fatigue damage simulation calculation method is presented based on the digital proving ground. The typical proving ground durability virtual digital pavement is built by the ADAMS, with the simulation and pavement test should obtain the dynamic load of the equalizing beam in the running state, LMSTecWare software is used to calculate fatigue damage of the pivotal load carrying structure. The contrast results of simulation and test indicate that the simulation results of the cumulative fatigue damage of the equalizing beam coincide with the pavement test very wel1, and the method can be use to carry out the fatigue life simulation and the fatigue life prediction of the pivotal structure of the heavy-duty truck, and reduce the new product development period and reduce the development cost.
Abstract: The inclinometers play a key role in the measurement of attitude angles of TBM. During the tunneling process, TBM suffers larger vibration and impact, because its construction environment is mostly mountain which is quite different from the ordinary shield tunneling machine whose is city soft soil. It will have an effect on the correct output of inclinometers in the position and orientation measurement system. Based on the principle of wavelet transform and vibration isolation, this paper presents a vibration error compensation method of the inclinometer to reduce the vibration error and fulfill the accuracy requirements of the attitude angles of TBM. On the basis of error analysis of the vibration measurement experiment of the inclinometer, process the vibration experiment data in different calibration angle and verify the efficiency of this method. Based on this method, it can eliminate the vibration error of inclinometers in any angle in time to achieve the purpose of output correction.