Use of identification and fault diagnostic methods for underwater robotics

The use of parameter identification and failure detection methods is considered with respect to ROV designed in Far Eastern State Technical University (FESTU). The parameter identification methods are applied for vehicle dynamic including determination of hydrodynamic and mass-inertial coefficients as well as for estimation of thruster parameters and tethered line reaction. Identification of hydrodynamic and mass-inertial coefficients is fulfilled by the direct minimization of an objective functional defined by a sum of squared errors between calculated and experimental records of the state variables. Modified gradient method is applied for reaching the functional extremum. An observer-based approach is considered to solve the problems of online failure detection in thrusters, sensors and online estimation of damping coefficients and tethered line reaction