This is less of a full soft robot than it is just a "component" to one. If you're familiar with the Soft Robotics Toolkit (softroboticstoolkit.com), then chances are you're familiar with the PneuNets Bending Actuator, which is a soft robotic "component" that, as it's name implies, bends. I've taken the basic principles behind this and modified it so that it exhibits linear motion as opposed to curving motion as seen in the PBA. I call my variation of this design the PneuNets Extending Actuator (PEA). I have fabricated this through use of 3D printed molds and Ecoflex 30 (Same material used in the Glaucus). Here are some pictures: http://imgur.com/ocsmkuO http://imgur.com/6LZS3XL
As this is still an ongoing project of mine, I am looking for ways to improve it. For example: unlike the PBA, the PEA does not have a strain-limiting layer, however, my actuator could benefit from one, but only if the layer was extensible but not bendable. Not really even sure if something like that exists . As I continue with this project I will probably post more updates.