Compensation algorithm of springback error in complex 3D sheet metal forming and experiment validation

Aiming at spring-back errors, a closed-loop accuracy control system for complex 3D sheet metal stamping is constructed. The computational formula of DMA (dies-modification algorithm) is derived in the prerequisite of small spring-back deformation and steady-going stamping process parameter. The algorithm based on the theory of linearity closed loop control system, space Fourier transform, transfer function in frequency domain and die experiment alternate. The validity of DMA for typical sheet metal stamping is systematically approved by experiments of multi-curvature bending and spherical surface shallow drawing experiment. DMA is used for the first time in the fabricating of complex 3D sheet metal stamping dies.