Tong Jiang

Influence on Inertia the Moment of Inertia Matrix of Three Degrees of Freedom Air-Bearing Testbed

To improve the accuracy of attitude determination and control stabilization when simulating attitude motion of satellites in the space, the finite element model of the platform of 3-DOF spacecraft attitude control simulator was founded. Gravity field of air bearing testbed and formula for platform’s moment of inertia on the action of gravity was induced The result shows platform’s attitude accuracy error exist because of main principal axis of inertia change of direction.on the action of gravity, The more large value it is, the more error is .Error of inertia main axis changes as sine curve with the change of two horizontal Euler angle.

Cutter Location without Interference Based on Nine Points Optimization Algorithm

Cutter location without interference is the key question in complicated surface NC machining. Starting with the theory of minimum directed distance, this paper, aiming at the problem of cutter location path without interference in the NC machining, reaches an important conclusion that the nine points optimization algorithm based on change step and change search range can get the global optimal solution. Meanwhile, this algorithm solves the astringency problem in iteration algorithm, and avoids a number of point set calculations in the whole area. Due to its features of fast calculation, simple principal and so on, it turns out to be a very effective method to calculate cutter path in NC machining of complicated curved surface.

Product Rapid Response Design Based on Knowledge Engineering

This paper introduces a mechanical product intelligent design platform. It presents a product information representation model, gives out the store structure, retrieving process of product cases and the usage of their knowledge for a new design. Finally, it gives an example of product design using this method, proving that it is quite good for product rapid responding design to meet fast changing market requirement and customer’s individual demand.

Investigations of Tool Wear with Water Vapor as Coolant and Lubricant in Green Cutting

Green cutting is one of the developing tends in the industry field. Water vapor can be introduced in metal cutting as coolant and lubricant due to its pollution-free, generating easily and unneeded disposal. Therefore, a special generating system is developed to produce suitable water vapor, and a simulation to the velocity of water vapor jet flow is presented. Then tool wear was investigated and a new capillary model is proposed, based on the experimental results. According to the boundary-layer theory, the kinetics equations of flow were solute. The velocity and flux of molecule are presented. In the capillary, the adsorption of tool-chip interface results in boundary lubricating film; the conical shape of capillary limits the depth of coolant and lubricant penetrating; and the negative press is the motility for coolant and lubricant penetrating. The study results show water vapor can decrease tool wear about 10% times and 20% comparing to cutting fluids and dry cutting, and water vapor could be a potential solution of green cutting.

A New Method for Hardened Gears Machining - Ausform Finishing Process

Ausform finishing process plastically deforms the surface of a steel component, generates compressive residual stresses in the surface layer, and imparts added strength and durability to the component. It integrates heat treatment, roll finishing and hardening of steel components into a single in-line manufacturing operation. The gear steel 20CrMo is introduced to determine various operation parameter of this process. The experiment results shown that ausform finished gears have the advantages of improved surface finish and profile accuracy.

Preliminary Approach to Mechanical Characteristics of Cement Mixed Superfine Iron Tailings

A large number of specimens with different contents of cement mixed superfine tailings, which took superfine iron tailings as aggregate, were produced to carry out a series of experiments on the mechanical properties of different ages and freeze-thaw cycling tests. The strength, load -deformation curve, frost resistance and other performances of cement mixed superfine tailings were obtained. The experiment data were compared with cement mortar and cement-mixed soil ones under the same conditions. The results are listed as follows: on even ground, the strength of cement-superfine tailings can be 4-6 times higher than that of cement-mixed soil, and about 10% lower than that of cement mortar; the relation of load-deformation and the characteristics of freeze-thaw cycles are basically the same as cement mortar under the same conditions.