Reduced-Order Modeling for the Development of AUV Motion Control Algorithms

Currently, the field of underwater robotics is actively developing. The scope of tasks performed by autonomous underwater vehicles (AUVs) is expanding, and hence, the requirements for their autonomy are growing. These factors inevitably increase the time and cost of designing control and navigation systems for AUVs; in this connection, mathematical simulation begins to play an increasingly important role. This paper proposes a method for designing a control system for AUVs based on reduced-order models formed as a result of numerical simulation. The novelty of the work is that the AUV motion dynamics is represented as modified nonlinear transfer functions with nonlinear time-varying parameters, which are supposed to be determined from the results of numerical simulation. The proposed approach makes it possible to decompose the problem of control algorithm design, reducing it to an optimization problem, taking into consideration the cross-effect of the control loops. This can cause difficulties in the case that traditional analytical models are used. The implementation of the proposed approach is described on the example of designing an algorithm for AUV control in the vertical plane when it moves at a specified distance from the seabed. The effectiveness of the method is con-firmed in the course of similar mathematical experiments conducted on numerical models.