Three-wheeled mobile robot called 'Becak' is one of the alternative transportation that generally used in developing countries. This research proposed a new design of the Becak to become autonomous vehicle one. This paper derived the kinematics model as a fundamental aspect of designing a mobile robot. Three-wheeled kinematic robot model that depending on the back wheel as initial robot velocity and the mobile robot turning angle determined by robot shaft angle. The model is obtained by assuming that a rotation merely depends on the robot shaft movement, as the front wheels both are standard fixed wheel. The rear wheel of the mobile robot also takes a standard fixed wheel. An additional assumption in this model is that there is a slip angle that affected the final pose of the mobile robot. The final pose of the mobile robot then calculated and simulated based on two input variables, i - e., rear-wheel velocity and robot shaft angle. The mobile robot trajectory plots are generated based on the proposed kinematics model.