This is a parametric pendant lamp shade created with Grasshopper (www.Grasshopper3d.com), which is a graphic programming environment plugin for Rhino. This instructable will cover how to manipulate the shape and design of the lamp using the included Grasshopper definition, as well as how to laser-cut the design, fold and assemble it. If you do not have access to Rhino and Grasshopper, you can skip to the cutting and assembly portion using the included Illustrator file with 3 lamp designs. If you do not have access to a laser cutter, but have a lot of time and patience, you can print out the designs from the included PDF and cut them out by hand.
All files are free to share, distribute, and learn from under the Creative Commons License.
This instructable was created at TechShop San Jose (www.TechShop.ws)
Step 1: Form Development
At the beginning of the Grasshopper definition, there is a group of attributes which manipulate the overall shape and size of the lamp.
The first curve manipulates the length and scale, in an exponential function. The second curve manipulates the shape of the swell, in a sine function.
The number sliders then divide that form into helical strips, and subdivide those strips into planar surfaces.
"Sides" changes the number of strips, "U div" changes the number of subdivisions or facets, and "Offset Holes" changes the size of the triangular holes in the facets.
Step 2: Interlocking Tabs
The design uses interlocking tabs to connect the strips. There will be no glue or fasteners necessary.
"Tab Depth" extends the tabs outward from the lamp, "Tab Width" changes the shape of the tab from rectangular to trapezoidal, and "Tab Angle" changes the width of the base of the tab.