Novel Design and 3-D Printing of Nonassembly Controllable Pneumatic Robots

Additive manufacturing (known as 3-D printing to the public) technologies are capable of fabricating mechanical parts without the limitation of geometric complexity. If properly designed, a mechanism can also be automatically fabricated without the need of assembly. Considering these capabilities of 3-D printing, this paper presents a novel pneumatic robot design that can be fabricated by 3-D printing processes without the need of assembly. The key element of the proposed robot is the innovative design of a pneumatic stepper motor that allows control of multimotion pattern modes. The proposed pneumatic stepper design is based on a fan motor, thus, having a low requirement on airtightness, which makes it possible for 3-D printing fabrication. For angular motion control, a roller valve is added to the fan motor design. By controlling the air pressure of the roller valve, continuous motion and stepping motion can be obtained. Experiments have shown that the angular velocity can also be controlled by varying the roller-valve air pressure. The effectiveness of the proposed concepts has been demonstrated by a 3-D printed nonassembly pneumatic robot. The printed robot, when connected with air tubes and a pneumatic controller, can perform simple pick and place operations. It is argued that the future functional nonassembly pneumatic robotic systems could be 3-D printed for relevant industries.