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Precision spherical joints are widely employed in parallel mechanisms, but its rotation orientation and angle can not be known in its passive motion. Measurement of multi-dimensional angular displacement will be very of great significance in the prediction, feedback and control of motion errors of parallel mechanism. Based on the magnetic effect, a new method to identify the orientation and rotation angle with Hall sensors array matched by permanent magnet is proposed. The basic idea is embedding a permanent magnet(PM) in the ball head and several hall sensors are distributed in the ball socket. When the ball head carrying the permanent magnet rotates together, the Hall sensors array will detect the variation of magnetic induction intensity, and then the angle can be calculated by mathematics model.

Based on the concept of dynamic servo, an electromagnetic coupling hybrid electric vehicle is developed. The system structure, working principle and control strategy of the vehicle are analyzed respectively. The simulation model of the vehicle is built using Matlab/Simulink software, and the output torque of ICE, EM and DRM is simulated in UDDS driving cycle. The simulation and test results show that the output torque can meet the requirements of driving cycle, and the efficiency of EM is always in high efficiency area.

Shearography is widely used in nondestructive testing because it has the advantages of full-field, robust, non-contact and high sensitivity. However, conventional shearography can only measure the first derivative of deformation in a single direction; multiple tests need to be done to obtain the first derivative of 3D deformation in different shearing directions. This paper presents a novel shearography system that simultaneously measures the first derivative of 3D deformation in two orthogonal shearing directions, one is in the x direction and the other is in the y direction. This system achieves dual-directional shearography by a modified Michelson interferometer. The object surface is illuminated by three different wavelengths of laser in different directions and a 3CCD color camera is used to record images. Different color shearograms recorded by 3CCD color camera were extracted respectively through channel separation, and cross talk does not exist.

The actual engine (especially vehicle engine) does not always operate under rated operating condition and its operating condition changes constantly. However, only the lubrication performance of crankshaft bearing at rated engine operating condition has been generally analyzed in current design and research of engine crankshaft bearing. In this paper, a four-stroke four-cylinder engine is taken as the studying object, the load and lubrication of crankshaft bearing under different operating conditions are analyzed systematically and comprehensively. The load of connecting-rod bearing is calculated by the dynamic calculation method, the loads of all crankshaft main bearings are calculated by the whole crankshaft solid-element finite element method, and the lubrication performance of crankshaft bearings are analyzed by the dynamic method.

This paper describes a simplified model to identify sprung mass using golden section method, the model treats the unsprung mass vertical acceleration as input and the sprung mass vertical acceleration as output, which can avoid the nonlinear influence of trye. Unsprung mass can be also calculated by axle load and the identified sprung mass. This study carries out road test on the vehicle ride comfort and takes a scheme that the group of 20 km/h is used to identify sprung mass and the group of 80 km/h is used to verify the identification result. The similarity of the results from the simulation and experiments performed are, for the sprung mass, 98.59%. A conclusion can be drawn that the simple method to measure the sprung mass in the suspension systems in used vehicles, such as the vehicle shown here, is useful, simple and has sufficient precision.

Light-weighting vehicles cause an increase in Aluminum Alloy stamping processes in the Automotive Industry. Surface finish and lubricants of aluminum alloy (AA) sheet play an important role in the deep drawing processes as they can affect the friction condition between the die and the sheet. This paper aims to develop a reliable and practical laboratory test method to experimentally investigate the influence of surface finish, lubricant conditions, draw-bead clearances and pulling speed on the frictional sliding behavior of AA 6XXX sheet metal. A new double-beads draw-bead-simulator (DBS) system was used to conduct the simulated test to determine the frictional behavior of an aluminium alloy with three surface lubricant conditions: mill finish (MF) with oil lube, electric discharge texture (EDT) finish with oil lube and mill finish (MF) with dry lube (DL).

It was simulated the temperature and thermal stress distributions of ceramics/metal functional gradient piston coating based on the third type boundary conditions of piston in IC engine under stable working conditions using the indirect solution method of thermal analysis and subsequently structural analysis by means of ANSYS10.0 finite element software. It was studied the effect of gradient composition distribution index p on the temperature of piston head and the thermal stress at the gradient layers of ceramics/metal. The optimal design result, as the gradient composition distribution index p = 0.6, could be obtained to relax the thermal stress.

The left-turn condition is the most complicated one at the unsignalized intersection, which is one of the key factors that affect traffic safety and efficiency. To solve this problem, this study proposes a distributed trajectory optimization framework based on the Gauss pseudospectral method (GPM). First, a circular obstacle based on the road size is constructed to replace the actual path constraint. The movement of obstacle is used for iterative calculations, and the trajectory of the left-turn vehicle is approached to the theoretical path. Then, for the multi-vehicle coordinated condition, the collision free constraints between vehicles is added to the optimization framework several times. In addition, the previous calculation result is used as the initial guess solution for the next calculation until all constraints are set.