Introduction: The First Snowfall Ornament: a Poetic Sphere
Step 1: Prepare the Text and Graphics
We started with the first stanza of the poem The First Snowfall by the American poet, James Russell Lowell (1819-1891). We centered the four lines of text and added some snowflake clipart in Powerpoint. The slide was then saved as an image.
Step 2: Time for MATLAB Coding!
We then imported the image into MATLAB for further processing. Our goal was to warp the image onto a sphere with the words and snowflakes recessed into the sphere's surface.
Step 3: Apply a Little Image Processing Magic
To make the text and graphics gradually sink into the volume, which helps prevent overhangs and improves printability, we applied a Euclidean distance transform using bwdist
Step 4: Map Image Onto a Sphere
Step 5: Mix & Slice
The .obj file was imported into Meshmixer where we added a loop for hanging and prepared the .stl files.
We sliced the .stl model using Sli3r with 0.2-mm layers and printed the design with our Printerbot Simple using red PLA filament. The ornament is printed as two hemispheres that can be glued together. Stick a LED throwie (sans magnet) inside for a little glow.