• origami
• pneumatic actuation
• pump
• shape memory alloy
• sma
• soft pump
• soft robotics

Soft fluidic actuators have become prominent, in recent years, in the development of novel soft robots, given their ability to expand, contract or bend. While they show major advantages such as a high specific power and a wide range of available motions, their major drawback lies in the need of a fluidic power source and a complex electromechanical system, which may result bulky.
In the state-of-the-art, several different means of providing pressure for an untethered operation have been used. However, all those methods present limitations as insufficient flow rate and pressure, limited volume capacity or complex modelling and control.
This master thesis focuses on the design and development of a new lightweight pumping device for soft robotics applications, that exploits Shape Memory Alloys and a purposely designed soft origami mechanical structure to produce a volumetric difference and the displacement of a stored fluid.
Taking inspiration from existing origami structures, that can theoretically guarantee a 100% volume variation, two models – the origami waterbomb and the kresling cylinder – were selected and their kinematic studied analytically. FEM simulations were performed to confirm the analytical modelling and get insights into folding behavior. Prototype were fabricated and a final selection was based on easiness of fabrication. The final prototype was actuated with SMA spring actuators and its performances were tested.