基于数字化模型的自由曲面打印研究

Research on freeform surface printing based on digital models

为实现手部自由曲面的精准功能化打印,提出了一种结合三维点云数字化成型工艺和自由曲面功能化成型工艺的方法。首先,通过三维扫描仪收集手部点云数据,并采用自适应加权引导滤波技术对曲面特征点进行平滑降噪处理;接着,使用基于曲率的自适应曲面几何采样算法在不丢失细节特征的同时对点云进行精简;随后,利用优化后的点云数据精确重构手部数字化模型,提取其自由曲面坐标并在其上设计功能化电路图案;最终,通过计算机辅助设计和矢量图形编辑软件生成的数控代码导入熔融沉积成型系统打印手部结构,并使用气溶胶喷射打印技术在手部自由曲面打印电子皮肤。试验结果表明,本试验采取的点云数据策略使手部扫描点的数量减少了80%,达到了明显精简的效果。手部逆向重构模型的误差在0.4 mm以内,相对于实物原型的拟合度较高。实证展现了电子皮肤在手部自由曲面一体化成型的潜力,并为高精度功能化打印提供了技术参考。

To achieve precise functional printing on the freeform surface of the hand,a method combining 3D point cloud digital molding process and freeform surface functionalization molding process is proposed.Firstly,the point cloud data of the hand is collected through a 3D scanner,and the surface feature points are smoothed and denoised using adaptive weighted guided filtering technology.Next,a curvature-based adaptive surface geometric sampling algorithm is employed to simplify the point cloud without losing detail features.Subsequently,the optimized point cloud data is used to accurately reconstruct the digital model of the hand,extract its freeform surface coordinates,and design functional circuit patterns on it.Finally,the hand structure is printed using a Fused Deposition Modeling(FDM)system with the NC code generated by computer-aided design and vector graphic editing software,followed by printing electronic skin on the freeform surface of the hand using aerosol jet printing technology.Experimental results show that the point cloud data strategy adopted in this experiment reduces the number of hand scanning points by 80%,achieving significant simplification.The error range of the hand reverse reconstruction model is within 0.4 mm,showing a high degree of fitting to the physical prototype.The empirical demonstration showcases the potential of electronic skin in the integrated molding of the freeform surface of the hand and provides a technical reference for high-precision functional printing.