I read the review[1] on flexible manipulators, the modeling method of multi-link(even if single-link) flexible manipulators seems very different from the continuum robots like OctArm(multi-section), hyper-redundant manipulator and etc which based on the backbone curve or constant curvature model.
[1]Sayahkarajy, Mostafa, Z. Mohamed, and Ahmad Athif Mohd Faudzi. "Review of modelling and control of flexible-link manipulators." Proceedings of the Institution of Mechanical Engineers, Part I: Journal of Systems and Control Engineering 230.8 (2016): 861-873. ,