Authored by Saarang Panchavati, Miller Lab, Rice University, July 2016 | Advisor: Jordan Miller
A Blender add-on for generating Intussusception fractal vasculature for 3D printing and computational fluid dynamics simulations and modeling.
Vascular networks designed with this add-on are featured in our Nature BME paper on laser-sintered carbohydrate templates for patterning complex tissue architecture.
Intussusception is the natural process by which one blood vessel splits into two. This add-on is an attempt to model this process in order to create functional positive flow models for 3D vascular networks. We create fractal vasculature by starting with a single tube and sequentially, dichotomously dividing all available tubes with each fractal generation.
Currently, this add-on allows the user to adjust the following parameters:
Print-ready scaling, length, angle, number of divisions, reduction in branching distance, inlet/outlet, bounding box, narrowing, space filling, skin radius, and Murray’s Law implementation.
This git repository includes: The python file for the add-on, and explanatory videos.
The tutorial videos below were taken in Blender 2.77a
. We provide an updated version for Blender 2.8x
as well as the legacy version for Blender 2.7x
.
-
First ensure you have downloaded and and installed the latest version of Blender. This add-on was originally developed and tested with
Blender 2.77a
, then upgraded for the newBlender 2.8x
Python API. -
Download this repository: https://github.com/MillerLabFTW/IntussusceptionAddon/archive/master.zip
-
Unzip the repository. You should find the required
IntusAddon.py
inside. -
In Blender, navigate to
User Preferences > Add-ons > Install from File
and find and select theIntusAddon.py
file in this repository and activate it. If you are usingBlender 2.7x
, use the fileIntusAddon_b2.7x.py
. Screenshots:
- Ensure it is checked in the add-on menu - It will be called
Add Mesh: Intussusception
- To use the add-on, in the 3D view window, type
<spacebar>
in the Blender Window and search forIntussusception
in the pop-up.
- You can adjust all the controls described above under
Overview
. To see what they will do, watch the videoIntus-Addon-Display
located in thePicsVids
folder of this repository.
Divisions
- Number of times the model divides
Length
- Adjusts length of the model
Angle
- Adjusts angle of initial branching
Reduction
- Adjusts amount by which the distance between branches decreases each division
Inlet/Outlet
- Adds inlet and outlet to model
Bounding Box
- Adds bounding box to model
Print Ready
- Adjusts model and bounding box scaling to 34x14x11 dimensions
2D Model
- Collapses Intussusception to 2 Dimensions
Narrow
- Moves back initial vertices to compact model, allowing minimal volume to be consumed by vasculature.
Spacefilling
- Moves groups of branches to be more space filling. Only works when Narrow
is on.
Skin Radius
- Adjusts the radius of the skin modifier on all vertices
Murray’s Law describes the relationship between a parent branch and its daughter branches wherein: r3p = rd13+ rd23 + … + rdn3
Murray’s Exponent
- Varies the exponent for Murray’s Law, which is generally 3
Equal Murray’s Law
- Applies Murray’s Law on the model, assuming that all daughter branches have the same radius
Random Murray’s Law
- Applies Murray’s Law on the model, but allows daughter branches to be of varying diameter