Conference Paper

In this work, a tactile force sensor based on fibre Bragg grating (FBG) is designed and introduced. The sensor is composed by two parts: metal casing, and FBG. The metal casing has a small diameter ring shape, namely, to accommodate the size of the fingers contact points. A thin metal sheet is soldered to the ring and an FBG is fixed on two sides of the ring and kept below the metal sheet. A small nut is mounted on top of the metal sheet to direct the force exerted by the finger contact point. The sensor was characterized by placing calibrated weights on top of 3 similar sensor structures disposed at equal distances for equal weight distribution. As the pressure increases, the metal sheet bends and the FBG is strained and red shifts. The sensor response time was ≈ 0.7 s and 1.1 s for the rise and fall time, reaching a pressure sensitivity of 3.7 x 10−6 nm/(N/m2). This work paves the way for the development of a multipoint tactile sensors able to monitor the pressure at the finger contact points, allowing its use in hand rehabilitation programs.