Delta DLP 3D Printing of Large Model
Published in IEEE Transactions on Automation Science and Engineering, 2017
Abstract: This paper presents a 3-D printing system that uses a low-cost off-the-shelf consumer projector to fabricate large models. Compared with traditional digital light processing (DLP) 3-D printers using a single vertical carriage, the platform of our DLP 3-D printer using delta mechanism can also move horizontally in the plane. We show that this system can print 3-D models much larger than traditional DLP 3-D printers. The major challenge to realize 3-D printing of large models in our system comes from how to cover a planar polygonal domain by a minimum number of rectangles with fixed size, which is NP-hard. We propose a simple yet efficient approximation algorithm to solve this problem. The key idea is to segment a polygonal domain using its medial axis and afterward merge small parts in the segmentation. Given an arbitrary polygon Q with n generators (i.e., line segments and reflex vertices in Q), we show that the time complexity of our algorithm is $O(n^{2}\log^{2}n)$ and the number of output rectangles covering Q is $O(kn)$, where K is an input-polygon-dependent constant. A physical prototype system is built and several large 3-D models with complex geometric structures have been printed as examples to demonstrate the effectiveness of our approach.
Recommended citation: Ran Yi, Chenming Wu, Yong-Jin Liu*, Ying He, Charlie C. L. Wang (2018) Delta DLP 3D Printing of Large Model. IEEE Transactions on Automation Science and Engineering, Vol. 15, No. 3, pp. 1193-1204, 2018.