Comparative Design and Experimental Evaluation of Low-Cost Pneumatic Continuum Soft Robotic Actuators Using Modular and Monolithic Heat-Sealed Architectures

Soft continuum robots offer safe human interaction and flexible navigation, but conventional systems relying on silicone molding or 3D printing present high barriers to entry. This paper presents the design, fabrication, and evaluation of two low-cost pneumatic continuum actuator architectures built from off-the-shelf low-density polyethylene (LDPE) polymer materials: a modular architecture using individually sealed longitudinal tubes for rapid repair, and a monolithic architecture utilizing a single folded sheet with strategic partial-seal geometries for programmable strain-based bending. Both systems are driven by a custom embedded pneumatic platform featuring an ESP32 microcontroller, eight relay-controlled channels, six miniature pumps, and six solenoid valves hosting a standalone wireless browser UI. We evaluate both architectures across manufacturability, leakage, modularity, and steering response, demonstrating that simple heat-sealed polymer actuators provide an accessible, highly effective platform for soft robotics research, education, and rapid prototyping.