Developing a Pseudo-Rigid-Body Dynamics Model for Pneumatic serpentine Robots

This study develops a strategy for modeling the motion of pneumatic serpentine robots, aimed at reducing computational costs and providing a modeling method consistent with the actual robot's motion response. Through mathematical modeling, we conceived a pseudo-rigid-body dynamics model of a soft serpentine robot connected by three pneumatic actuators. In this design, we connect the links via twist springs acting as one bidirectionally bendable pneumatic actuator, with the goal of approximating the motion response between the simulated and real soft serpentine robots. Furthermore, we refined the traditional linear spring model by incorporating the characteristics of pneumatic actuator pressure-driven signals, deriving an actuation model capable of mimicking real pneumatic drive forms. Under this model, the simulated robot was able to achieve a typical undulation locomotion. Compared to existing soft body modeling methods, our proposed modeling approach significantly reduces computational costs.