Ya Zhe Chen

Pedestal Looseness Fault Analysis of Overhanging Dual-Disc Rotor-Bearing

Looseness fault can occur in rotor part, bearing and pedestal for the vibration caused by alteration of operating craft and inappropriate installation. In the paper, a new pedestal looseness model is proposed by comprehensively considering the advantages and disadvantages of current models of pedestal looseness. By using nonlinear finite element method, the nonlinear characters of overhanging dual-disc rotor bearing for pedestal looseness fault are studied. The work has important significance on safe running and prolonging the life span of machines.

Research on the Product Quality Control Based on the Systematic Design Process

It expounded the design quality connotation, product generalized quality was “the integrated embodiment of product function and performance”, the generalized product quality and the whole function and performance are equivalent. Clearly it made the design quality concretized into the product function and three performances. Expounded the concept of product design quality control, analyzed the influencing factors of product design quality, formed the design idea of quality control; aiming at the existing problems of traditional product design, established design quality control preliminary model by applying systematic design theory.

Dynamic Analysis of Rubbing Rotor System Based on Hertz Contact Theory

When discussing the rubbing issue of rotor system, the effect of nonlinear rubbing force is needed to be considered. In this paper, modeling and numerical simulation were carried out by using the nonlinear rubbing force based on Hertz contact theory, and researching the dynamic response of fault rotor system in the conditions of the different rubbing stiffness. Through the analysis we found that, in the case of larger rubbing stiffness the result simulated by using rubbing force model based on Hertz contact theory has stronger nonlinear and more obvious rubbing feature, compared to the rubbing model of linear stiffness. It is beneficial to determine the occurrence of rubbing. Refer to the relevant experimental results, the correctness of the Hertz rubbing model and the feasibility of applying it in the modeling of rubbing rotor system were confirmed.

Failure Analysis and Reliability Evaluation of a Planetary Gear Box

With the qualities of smooth operation, high efficiency and small size, the planetary gear box was widely used in transmission field. In this paper, a 2-stage planetary gear box was studied. CAXA and Pro/E were used for modeling. The FEA analysis results were obtained by ANSYS, both the contact stress and the bending stress of the gear tooth root. The results showed that with the continuous action of cyclic loads, the excessive contact stress is the direct reason of the failure. Then, the system reliability evaluation was made, which can provide guidance for engineering practice.

Research on Optimization Model Based on House of Quality Fuzzy Theory in Industrial Environment

In this paper, under House of Quality(HOQ) Fuzzy Theory, taking product planning House of Quality(HOQ) as an example, systematically considers fuzzy auto-correlation matrix of engineering properties influence on engineering properties target value and development cost, by definition some concepts, such as engineering properties plan improvement level, practice improvement level, fuzzy planning cost coefficient and fuzzy actual cost coefficient, establish properties target value optimization model based on House of Quality(HOQ) Fuzzy Theory, and validate this method by a case study.

The Research Status and Existing Problems of Microscopic Visual Servoing Based on Image

This paper introduces the basic principle of the microscopic visual servoing system based on image and summarizes systematically about the researching situation of microscopic visual servo based on image at home and abroad. From three aspects, which are Jacobin matrix calculating, automatic focusing technology of microscopic lens, and microscopic image fusing technology, it proposes some key problems to be urgently solved about the microscopic visual servoing based on image.

Experimental Investigation of Rotor Rubbing Faults

Established a single-disc rubbing rotor system test-bench ,and can simulate the design of a single point of rubbing and rubbing of the rotor part. In the case of constant speed to ensure that observed in the rubbing rotor vibration under different conditions, the use of waveform, frequency spectrum, Orbit and other detailed analysis of the system before and after rubbing and chaotic properties of nonlinear response the experimental. results show that the occurrence rub rotor system, the system will stimulate a high frequency and fractional-octave, when there will be a serious rub chaos.

Nonlinear Dynamics of Jeffcott Rotor System with Rub-Impact Fault

The rub-impact fault of Jeffcott rotor system which is generally made of an elastic shaft with supported by two bearings at ends and a lumped mass at the mid-span of shaft is the main research subject of this paper. The mechanical model and finite element model of a lump mass at the mid-span of shaft is set up. The dynamics of it are studied by nonlinear finite element method under the rub-impact conditions, and by investigating the effects of stiffness of stator and the clearance between rotor-stator. From the study results, use finite element method to study the rotor system failure problem is intuitive and convenient, high accuracy, high reliability, can be widely applied.

Comprehensive Evaluation for Generalized Product Quality Based on Fuzzy Entropy

With a view to improving product quality, the concept of generalized product quality is proposed and analyzed in depth to frame a comprehensive fuzzy evaluation system for generalized product quality, which includes all the constructional, operational and technological performance and function and takes account of the hierarchy and complexity of such an evaluation system. In the system the weighted value for each and every evaluation index is determined by combining entropy weight with subjective weight so as to make the evaluation more objective and scientific. Comparing with the method of comprehensive fuzzy evaluation, the evaluation system thus framed gets rid of the empirical subjectivity in determining index weight, thus enhancing the dependability of the weight, as a result, such an evaluation will be more reliable.

The Mechanism Design of the Upper Air Crawling Robot

The thesis designed a robot which can crawl along the mast or the rope, introduced this robot’s composition and his function, and carried on the kinematics modeling, analysis and simulation design to the robot. The crawling robot can carry the detector set to inspect the mast or the rope.