This paper investigates to design a controller for maritime autonomous surface ship (MASS) by means of adaptive super-twisting algorithm (ASTA). A input-out feedback linearization method is considered for multi-input multi-output (MIMO) system. Sliding Mode Controller (SMC) is suitable for MASS subject to ocean environments due to its robustness against parameter uncertainties and disturbances. However, conventional SMC has inherent disadvantages so-called, chattering phenomenon, which resulted from the high frequency of switching terms. Chattering may cause harmful failure of actuators such as propeller and rudder of ships. The main contribution of this work is to address an appropriate controller for MASS, simultaneously controls surge and yaw motion in severe step inputs. Proposed control mechanism well provides convergence bewildered by external disturbances in the middle of steady-state responses as well as chattering attenuation. Also, the adaptive algorithm is contributed to reducing non-overestimated value of control gains. Control inputs of surge and yaw motion are displayed by smoother curves without excessive control activities of actuators. Finally, no overshoot can be seen in transient responses.

Abstract
 1. Introduction
 2. Ship Dynamics and Control Synthesis
  2.1 Ship Dynamical Model
  2.2 Adaptive Control Synthesis
 3. Simulation Tests
 4. Conclusions
 References

• Sang-Do Lee(Korea e-Navi Information Technology Co. LTD.)
• Xiao Xu(Department of Logistics Engineering, Korea Maritime and Ocean University)
• Hwan-Seong Kim(Department of Logistics Engineering, Korea Maritime and Ocean University)
• Sam-Sang You(Division of Mechanical Engineering, Korea Maritime and Ocean University) Corresponding Author