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For automated fiber placement machine, tensioner is one of the important modules, which precisely generates and controls the tension of fibers.This paper performs a system analysis and synthesis of the key technologies of tensioner in recent years by summing up the development course of the tensioner. A new type of tensioner specially designed for fiber placment technology is presented. Experiments results prove the feasibility of the proposed mechanism and control algorithm. In addition, this paper also aims at giving a perspective in such area in the future.

To overcome the difficult in modeling the mode theory for magnetic flywheel, by non-parametric frequency domain identification method for identification of system model, this paper select the PID neural network nonlinear intelligent control methods based on GA. Used a method based on iterative process to suppress the resonance, combined with zero-pole theory, this research designed a GA-based PID neural network identification controller to address the modal vibration suppression problems in the external rotor flywheel .The experiments for this paper proved the effectiveness of iterative process, and the controller can restrain the system mode vibration well.

Micro-end-milling tools are suitable for machining miniature parts which have complex shape. As the diameters of tools are too small, cannot directly obtain the frequency response functions (FRFs) through impact hammer test at tool tip. This paper employs Receptance Coupling method (RC), couple the tool tip’s FRFs with machine-toolholder system’s FRF, and then get the micro-end-milling tool’s FRF. Establish the coupling model, then finite element and hammer test of the blank gauge tools are used to obtain the coupling transfer functions (TFs). Then analyze the tool tip model by finite element, couple with the machine-toolholder system hammer test result and coupling transfer functions, finally the micro-end-milling tool’s FRFs are obtained. Through the hammer test of blank gauge tool, the effectiveness and feasibility of RC method are verified. The result shows that the RC method is accurate at micro-end-milling tool in steady state milling.

The micro crowled integral impeller is one of the key parts of aeroengine. It is difficult to machine for its complex structure and small dimension. In this paper, the tool path planning scheme of micro crowled integral impeller is researched, which lays foundation for the numerical control machining of the part. To begin with, considering the feature of impeller’s structure, a kind of processing route is proposed and the processing regions are divided, which satisfy the demand of accuracy and efficiency. Then, the tool path planning scheme of the impeller is put forward, which is regular and is more suitable for a large-diameter tool to fulfill the machining process. Finally, machining simulation is carried out to prove the feasibility and correctness of the proposed path planning scheme.

To improve production quality and reduce machining time, machining parameters need to be monitored and adjusted automatically in milling. An integrated controller which is modular, configurable and based on OMAC, is established. The hardware platform, resultant cutting force constraint and its fuzzy control rules have been introduced in detail. In the fuzzy controller designed, two inputs and one output are used with five fuzzy sets for the controller, and the output rate of feed-rate can be changed from 50% to 200%. This controller has the abilities of reducing fluctuation range of cutting force, adjusting feed-rate intelligently, which is a part of CNC system. The experiment results show it can realize the real time status monitoring with this system, reduce the cutting force fluctuation, and adjust the feed-rate intelligently during machining.

The influence of preheating adopted and preheating unadopted on manufacturing speed during the automated fiber placement process has been analyzed. According to Fourier heat equation and assuming the towpreg with uniform material properties, a heat transfer model of towpreg has been established. The boundary conditions and initial conditions of this model at different stages have been given based on energy exchange principle. The research chooses thermoplastic composite APC-2(carbon/PEEK) as the towpreg material and utilizes the finite element method to investigate the temperature history of the fiber placement process. Since fiber placement speed is related with the response time of temperature, it can be obtained by the temperature history. Finally, the results demonstrate preheating can significantly improve the fiber placement speed.

The numerical simulation of hot-stamping process was carried out for UHSS square-cup parts, and the influence of dies temperature on the hot-stamping process was anlysised. Besides, through the microstructure analysis and mechanical properties testing of the formed parts, effects of dies temperature on microstructures and mechanical properties of hot-stamping square-cup parts were obtained. The experiment and simulation results showed that the mechanical properties of the UHSS are strongly dependent on the temperature, so the dies temperature is one of the most important parameters that have to be taken into account in designing the hot-forming dies and the hot-forming process.