Loading trajectory is the key factor in skin stretch forming. First the loading trajectory of double curve skin was designed through the analytic method, then the parameters were changed to the machine-s instructions which were used as design variables. The method of combining finite element analysis and optimization algorithms was proposed to acquire the reasonable loading trajectory. Optimization mathematics model was set up in order to reduce springback and improve the fittability. The reasonable loading trajectory was found through the numerical simulation and sequential quadratic programming optimization algorithm under the restrictive of maximal thickness strain. Experiment was done according to the reasonable loading trajectory. Both numerical simulation and experiment results show that the precision, strain distributing and thickness uniformity of skin are improved greatly.
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��,���ͱ�,���,��. �ɻ�������Ƥ������ֵģ��ϵͳ�������ؼ������о�[J]. ����ѧ��,2004,25(6):606-610 Bai Di, Zhou Xianbin, Li Dongsheng, et al. Key technology research and system development of complex aircraft skin stretch forming simulation[J].Acta Aeronautical et Astronautic Sincia, 2004,25(6):606-610(in Chinese)
�����,���ͱ�. ��Ƥ���λ������˶�����[J]. �������켼��,2004(1):85-88 Liu Yicheng, Zhou Xianbin. Mechanism motion analysis of the skin stretch-forming machine[J].Aeronautical Manufacturing Technology, 2004(1):85-88 (in Chinese)
Liu Gang, Lin Zhongqin, Bao Youxia. Optimization design of drawbead in drawing tools of autobody coverpanel[J].Journal of Engineering Materials and Technology.2002,124(2):278-285
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