A Light Soft Manipulator With Continuously Controllable Stiffness Actuated by a Thin McKibben Pneumatic Artificial Muscle

Soft continuum manipulators based on pneumatic artificial muscles offer the advantages of high compliance, complex environmental adaptability, and safe interaction with humans and work environments. However, most of them cannot continuously change their stiffness under a fixed end position due to the strong coupling of position and stiffness. To overcome this problem, this article develops a light soft continuum manipulator with a continuously controllable stiffness based on thin McKibben pneumatic artificial muscles. By controlling the external 2.0 mm muscles and the internal 1.3 mm muscles, the position and stiffness are decoupled. The math model is established, and the validity is verified by experiments.