I choose to use the Overgaard Dyrman Wire Collection Dinining Chair as my base for parametric extension.
Original Chair:
I began by building the model in Rhino, basically projecting points from the elevations of the chair and creating curves between these points. From the curves I created a lofted surface. I used the lofted surface to interpolate curves on the surfaces to create the series of wires that create the structure of the chair. From there I was able to split the lofted surface to create the cushion. The legs were made by projected points from the elevations and drawing curves. At the end, I swept circles around the curves to create the piping.
After the model was built in Rhino, I transferred the construction of the geometry to functions in Grasshopper where I was able to add variable sliders to create different outcomes for the width, cushion density and number of bars.
Parametric Modification of Chair using width, num bars and cushion density:
DRIVER 1: Width
DRIVER 2: Num Bars
DRIVER 3: Mesh Density
Parametrics 