Step 1b: Create Fibers

Create fibers

The second major component of the actuator is the set of fibers around the outside. To create these fibers, double click on Part again. Name the part ‘fibers’ and make it a 3d Point. Hit enter to accept the default of (0.0,0.0,0.0) as the coordinates.


Go to File->Run Script. Browse to the file and run it. This file creates a helical wire structure, with radius 8.35mm, height 163mm, and fiber angle 3°. An actuator with this fiber angle will extend and twist upon pressurization.

Note: the fiber angle can be changed by modifying the parameter ALPHA in

For a bending actuator, run the file This will create a symmetric arrangement of fibers (fibers at equal and opposite angles).


To view the fibers, click on Apply Iso View.

Add fibers to assembly

Now we will make a set containing the fibers, as we will use this later in the model. In the model tree, expand Parts->Fibers and double click on Sets.

Name the set FiberSet and click Continue

Click on the fibers to select them as the geometry for the set, and click Done.  

To add an instance of the fiber to the assembly, expand the assembly tree, double click on Instances, select ‘fibers’ in the Create Instance box, and click OK.