In this study, an inhomogeneous Cosserat rod theory is introduced and compared to the conventional homogeneous rod for modeling soft manipulators. The inhomogeneity is addressed by considering the pressure actuation as part of the rod's constitutive laws, resulting in shifting the neutral axis. This shift is investigated for a soft manipulator with three parallel fiber-reinforced actuators. Furthermore, a fiber-reinforced actuator is modeled using nonlinear continuum mechanics to extract the effect of radial pressure on axial deformation and is combined with Cosserat model. Finally, several numerical methods are employed to solve the proposed model and validated by a series of experiments.

翻译：本研究提出了一种非均匀Cosserat杆理论，并将其与常规均匀杆模型进行对比，用于软体机械臂的建模。通过将压力驱动视为杆本构律的一部分来表征非均匀性，由此产生了中性轴的偏移。针对具有三个平行纤维增强驱动器的软体机械臂，研究了该中性轴偏移现象。进一步地，利用非线性连续介质力学对纤维增强驱动器进行建模，提取径向压力对轴向变形的影响，并将其与Cosserat模型相结合。最后，采用多种数值方法对提出的模型进行求解，并通过系列实验验证了其有效性。