1 Using Voxelization and Ray-Tracing to Identify Wall Thinness of ...

for printing. This technique can be used to quickly identify issues with models before sendingthem to the 3D printer, which can prevent troublesome prints, saving both material and time.The algorithm uses a series of three repeating steps. First it voxelizes a portion of theinput model. Next it uses ray-casting to define the voxels that are interior to the model. Finally, ituses a sort of flooding technique to characterize each voxel according to its distance from the'center' of the nearest interior wall. These steps repeat until the entire model has been processed,and then a highly customizable visualization of the result is printed to an X3D file. This filehighlights overly-narrow sections of the input model that are possibly structurally instable andthat could lose detail in the printing process, compromising the customer's vision of the finishedproduct.To save space, the algorithm utilizes an octree implementation. It is very efficient interms of memory consumption, accepting input models of varying sizes and processing them to auser-defined level of resolution. It allows scaling up to and beyond volumes of 1024x1024x1024voxels. It is computationally efficient as well, traversing the geometric model just once.Additionally, the method does not depend on GPU (graphics process unit) hardware in order toperform its computation, so it can be used on any personal computer.4Figure 1: Example of a 3-D model created by a 3D printer [1]