Measuring the Bending Performance of Fiber-Optic Cable SheathsThe ability of fiber-optic cable to resist damage during placement and handling depends on its tensile and bending characteristics. If cables are bent to too small a radius, they will buckle, and the optical fibers can break. Thus, the safe bending radius is an important parameter that influences installation techniques and choice of equipment. A related parameter is bending stiffness. Cables that are too flexible can be accidentally bent to tight radii and fiber damage can occur. On the other hand, stiff cables can be difficult to handle. Clearly, a knowledge of the parameters controlling flexibility and buckling is needed in order to design cables that can resist damage and be handled easily. This paper describes analytical and experimental techniques that may be used to obtain such knowledge.
A new apparatus has been built to measure the bending moment applied to cables over a large range of curvatures and strains.
--D. E. Hart et al., "Closed-Loop Shape Control of a Roll-Bending Process," ASME Journal of Dynamic Systems, Measurement and Control