State Observer-Based Sampled-Data Control for Path Tracking of Autonomous Agricultural Tractor

This study develops a sampled-data controller for the path tracking system of an autonomous agricultural tractor (AAT) on the basis of a state observer. First of all, to solve the cost of the whole system, the state observer is constructed for estimating the heading offset and for accelerating the convergence process. Built on the observer, an advanced output feedback sampled-data controller is formulated, which tackles the problem of slow data freshness caused by the low signal frequency of the GPS-RTK system. Subsequently, a Lyapunov stability analysis is conducted to guarantee that the AAT system can be stabilized under the proposed control strategy. Finally, comparative simulation results are provided to illustrate the efficacy of the control strategy.