3D-printing allows for fluid-controlled linear actuators with unconventional shapes.

Area of Science:

• Additive Manufacturing
• Robotics
• Biomedical Engineering

Background:

• Pneumatic actuators are crucial components in medical robots and prostheses.
• Traditional manufacturing of pneumatic actuators involves complex processes and standardized dimensions, increasing costs.
• 3D-printing presents a cost-effective and efficient alternative for producing pneumatic actuators, particularly in medical applications.

Purpose of the Study:

• To investigate the feasibility of fabricating pneumatic linear actuators using 3D-printing technology.
• To explore the creation of pneumatic actuators with non-circular cross-sections by leveraging 3D-printing capabilities.

Main Methods:

• A test setup was developed to evaluate the performance of 3D-printed pneumatic actuators, focusing on leakage and sliding friction.
• Two pneumatic actuators with non-conventional cross-sectional shapes were designed and tested.
• Performance was compared against a 3D-printed cylindrical pneumatic actuator, with no post-processing applied to the printed components.

Main Results:

• Functional 3D-printed circular pneumatic actuators demonstrated low static (2.5%) and dynamic (approx. 1%) leakage rates, with a maximum friction force of Image 1.
• Successful fabrication of pneumatic cylinders with non-cylindrical concave cross-sections was achieved.
• Non-conventional cylinders were tested up to Image 2, exhibiting maximum dynamic leakage rates of Image 3.

Conclusions:

• This research validates a method for producing functional pneumatic linear actuators via 3D-printing.
• Both conventional (circular) and unconventional (stadium/oval, kidney) shapes were successfully printed.
• Leakage rates for conventional and unconventional 3D-printed actuators were comparable, indicating expanded design possibilities.