Fibre Bragg grating (FBG) sensor system for highly flexible single-link robots

This paper presents a sensor system based on optical fibre sensors (FBG) with which to measure the deflexion of a highly flexible lightweight beam. Epoxy glue is used to attach these optical sensors to specific locations on the surface of the beam in order to measure local strain measurements. These strain measurements, provided by FBG sensors, are used in a method proposed in this paper to estimate the deflection of the beam (the tip position and the tip rotation angle) in both static and dynamic cases. The correct number and the optimum distribution of the sensors on the beam are chosen by using the Chebyshev criterion which minimizes the error in estimating the position and the rotation angle of the tip link. Static and dynamic experiments are presented to verify the effectiveness of the estimation method and the sensor system proposed.