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In this study, a mesh stiffness model of spur gear drives considering the tooth corrosion effect, which is based on Ishikawa model, is proposed. The fidelity of mesh stiffness based on the proposed model is checked by comparing the result with a benchmark result from the reference and the effect of the tooth corrosion on mesh stiffness is analyzed. The prediction indicates mesh stiffness is insensitive to the tooth corrosion, but this conclusion has a signification for assessing the stability of inherent properties of a spur gear drive when the tooth corrosion is produced.

For small area estimation (SAE) Spatial Empirical Best Linear Unbiased Prediction, SEBLUP, is involved in linear mixed model with spatial correlation while Empirical Best Linear Unbiased Prediction, EBLUP, often with mutual independence. In this paper, we discussed maximum likelihood estimation (MLE) and compared the efficiency. Simulation shows that SEBLUP with spatial correlation data of spatial small area is more effective than EBLUP.

Damping property analysis of laminated composite structures have been done based on the complex stiffness method (CSM). In view of laminated plates with viscoelastic material cores, investigation is conducted using CSM and numerical methods of finite element method and spectral finite element method. Simulation results show that analytical solutions by CSM are in good agreement with the two kinds of numerical solutions. The proposed analytical method is well suited to calculate and optimize the damping property of laminated structures especially composites with constrained layer damping treatment.

The ANSYS harmonic response results are post-processed with the energy method to obtain the damping loss factor (DLF) of different types of free damping structures. Firstly, the DLF of free damping cylindrical shell in air is compared with DLF of free damping plate in air. Secondly, the DLF of free damping cylindrical shell with stiffened ribs in air is compared with that without stiffened ribs in air. Thirdly, the DLF of free damping cylindrical shell in water is compared with the DLF of free damping plate in water. Fourthly, the DLF of free damping cylindrical shell with stiffened ribs in water is compared with that without stiffened ribs in water. In the end, based on the above analysis, the backing design problem in air and water are discussed. Studies have shown that: DLF of free damping cylindrical shell is close to that of free damping plate in air; DLF of free damping cylindrical shell with stiffened ring ribs is close to that without stiffened ring ribs in air; When testing free damping cylindrical shells DLF in air, plate with the same thickness can be used as the backing; DLF of free damping plate is close to that of free damping cylindrical shell in water; DLF of free damping cylindrical shell with stiffened ring ribs is close to that without stiffened ring ribs in water; When testing free damping cylindrical shells DLF in water, plate with the same thickness can be used as the backing.

Due to the problem of the mutual interaction between the polishing tool system and the control of poses and positions, it is difficult to hybrid-synchronizationally control the polishing force, the posture of polishing tool head and the polishing trajectory. So the article designed a set of compliant tools that take the pneumatic servo system as the control system, which was used for active polishing aspheric surface of Robot. It was to accomplish the Robots self-adaptive control to the posture of the polishing tool as well as to figure out the correlation of the contact deformation between the polishing tool and the work piece surface, which makes a theoretical analysis on dynamic and steady characteristics of the contact deformation of the tool system. It applied the meek and polishing tools to the polishing processing of the rough machining of large aspheric surface samples to obtain the data. According to the statistics, the polishing tools can effectively solve the problem of the mutual interaction between the polishing tool system and the control of poses and positions. It also owns good adaptive ability and its machining aspheric surface quality can achieve nanoscale.

Unbalance is one of the main vibration sources of rotating machinery. Study on the response of unbalance is important for the machine tool spindle dynamic performance evaluation and balancing technology. How to simulate the unbalance automatic generation and how to effectively analyze the unbalance vibration signal are two main problems. In this paper, an electromagnetic balancer is used to act as the unbalance generator to imitate the tool unbalance during machine tool operation. An integrated spindle with the balancer is developed and the acceleration and displacement sensors are applied to pick up the unbalance vibration. The filtering, linear FFT and averaging are applied to extract the fundamental component from the original signal. The displacement peak-peak value and acceleration peak value are chosen as the characteristic parameter evaluating unbalance response and the shaft orbit is adopted to recognize unbalance intuitively. The experimental results show that the unbalance simulation and signal analysis method are feasible and effective.

Based on wet paper code, integer wavelet and matrix coding, this paper constructs a new steganographic algorithm. Combine with the advantage in integer wavelet domain, which more close to HVS, a part of secret messages are embedded by LSB in high-frequency coefficients after integer wavelet switch, wet paper code is used to change the direction of embedding. Another part of secret messages are embedded by matrix coding in low-frequency coefficients after integer wavelet switch, wet paper code is still used to change the direction of embedding. The performance of the proposed approach shows that security and capacity of secret messages are improved in integer wavelet domain.

For coupled plate-shell structure, restraining the vibration transmitted from plate to shell is an important approach to reduce the mechanical noise from the shell. In this paper, a damping sandwich arch profile with rubber as the material of the damping layer is presented and manufactured. Structure vibration response with arch profile applied to the coupled plate-shell test model is measured. And then Statistics Energy Analysis method is used to analyze the effects of major parameters on anti-vibration performance of the arch profile. Research indicates that using damping sandwich arch profile can restrain the vibration response of the shell effectively.

First it sets up a kinematical model for a kind of industrial robots by D-H notation, and inverse kinematics solutions of its end effector are deduced according to its motion trail. By transforming the rotation angles of the robot’s joints into impulse signals, pulse signals could be used to interpolate its motion trail. Finally, it uses Matlab software to join various curve of each joint impulse signal, and formulation a mathematical model about various curve of each joint impulse signal. In this way, it could simplify program in INFORM Ⅲ language. Simulation shows that direct pulse signal interpolation improves the accuracy of trajectory positioning.

In order to process the hardened face-gear, the worm for face-gear is studied. The research includes designing and dressing method of worm. According to the meshing relationship of face-gear, worm and shaper, coordinate systems of face-gear, worm and shaper are established. By envelope theory, the face-gear tooth surface are obtained, worm tooth surface and shaper tooth surface. The solid models of face-gear, worm and shaper were built, and the approach of dressing was simulated for hardened face-gear processed.

Machining slender workpiece is still a technical difficulty. This paper investigates the dynamic behavior of a slender shaft subject to constant feedrate moving cutting forces in twin-spindle turning process. The Euler-Bernoulli theory is used to model the rotating shaft. A dynamic cutting force model is formulated considering the flexibility of workpiece and rigid machine tool. The modal analysis method is employed to solve the dynamic response of the shaft. The parametric influence to the response and natural frequencies of shaft is discussed. Finally, the results are presented and compared between constant cutting forces and deflection-dependent force model introduced in this paper. It is found that there exists a stiffening effect due to the cutting process.

In order to process the hardened face-gear, and improve the surface’s accuracy, the grinding process of face gear is studied. According to the equation of tooth surface, the tooth surface is drawn by a series of space curve, the contact point’s trajectory and velocity at the processing of grinding are determined in three coordinate directions. The model of grinding machine is set up, and analyses the movement of relationship between tool and face-gear. The simple grinding wheel apply complex movement to grinding process the face-gear is successful.