A sailboat robot is a highly nonlinear system but which control is relatively easy, however. Indeed, its mechanical design is the result of an evolution over thousands of years. This paper focuses on a control strategy which remains simple, with few parameters to adjust and meaningful with respect to the intuition. A test on the sailboat robot called Vaimos is presented to illustrate the performance of the regulator with a sea experiment. Moreover, the HardWare In the Loop (HWIL) methodology has been used for the validation of the embedded system. Last point is that this HWIL simulation compared to the real experiment is also a confirmation that the dynamic model used for control is correct.