Self-uncoupling wrist six-axis force/torque sensor based on Fiber Bragg grating

Force/torque detection of the robot’s end is the key to achieving the precise control of the robot. However, sensors used for multi-axis force/torque detection often have dimension coupling problems and require additional complicated decoupling. In this work, we proposed a novel self-uncoupling six-axis force/torque sensor based on the fiber grating. It uses a layered measurement design method to achieve low coupling and high sensitivity with the help of special orthogonal decoupling combined beam structures. In addition, the decoupling and temperature compensation are realized by the wavelength shift difference of FBG, which reduces the number and complexity of sensitive elements and increases the anti-electromagnetic interference capability. Finally, the simulation and experiments show that the sensor not only has good static and dynamic characteristics, but also has good linearity, low hysteresis, high sensitivity and high resolution.