Sasa Zivkovic Grasshopper Tutorial 01

MIT Department of Architecture 4.113 4.113 Applied Architecture Design Studio I, Spring 2011, M/WF 2:00-5:00 Instructors: Skylar Tibbits, Nick Gelpi Teaching Assistant: Joshua Cotton, Sasa Zivkovic

Grasshopper tutorial | Creating a 3D box array Open Grasshopper by typing “Grasshopper” into the command line. The Grasshopper window looks like this:

Tools and components can be found in the tab line [Params, Logic, Scalar, Vector, Curve, etc.] Other important info: egg symbol – bake your geometry in Rhino symbol right from the egg: visibility modes for Grasshopper geometry blindfolded person – disable preview for selected component

Step 01 | Creating a 2D G rid > Different grid geometries can be found in the command tab “vector – select one and place it in the Grasshopper document. > Create a 2D grid b y defining input parameters [size of grid cells, expansion in x-and y direction]. Use number sliders in order to later adjust the size of your grid. > The grid component will give 2 output parameters: the grid cell outlines and a set of points

Step 02 | 3D Grid > There are different ways of adding the z dimension to the grid: We will duplicate the 2D grid and copy it in relation to the size of your initial 2d grid cells. In order to do this a vector needs to be defined along which the grid duplicate can be moved. > a vector can be created from two points: follow this logic: create a series of numbers [logic tab] and use the size of your 2D grid as an input for the step size as well as the input for the first number of the series [this will ensure an equal grid size in all three dimensions]. The series parameter will give you an output of numbers which we can use to define the end points of our vectors. > Points are defined by their x,y and z values within the Rhino coordinate system. Create points by using the output of the series to define z-coordinates. [vector tab] . Create a point with 0/0/0 value and use both components to create vectors. > You You can use a slider to define the number of values in your series: in this case you will end up with 6 vectors. This will enable you to control the number of d uplicates in z-direction.

Step 04 | Duplicate the 2D grid points > Create a 'move' component and connect it with the vector as well as your input geometry [points]. Due to internal organizational logics this will result in an unwanted move without duplicates. In order to successfully duplicate we need a 'graft' component to flatten our internal organization of the point grid [see yellow boxes]. We'll explain the logics of list management later... later... > we now have a parametric grid of points which can be modified in all three dimensions by moving the number sliders.

Step 05 | Create a geometry based on point input > Attractor: Draw a point in Rhino/ go to 'Params' and drop a point parameter / right click and add the rhino point > Create attractor vectors that go from e ach point of your grid to the attractor point > Use your attractor vectors to create a perpendicular plane [in relation to the to the vectors] at each point of your grid > Use the planes to orient/create boxes [grid point = center point of box] > Compute the length of of your attractor vectors (number will be too high of an input for as a scale factor therefore divide the vector length using a number slider) > Scale your box geometry in relation to the length of the attractor vectors

Step 06 | Bake your geometry > Select your final output parameter and press bake to transfer your geometry into rhino. > bake different 3d arrays (size, density, box properties) > use different geometries (sphere, pyramid, cylinder, cone, etc.) > test different operations (scale, rotate, shear, etc) > test different grids