The current work proposes an optimization system in the positioning method for mobile robots which will allow to increase the accuracy in a previously defined trajectory. Mobile automatons with predefined routes tend to have cumulative error in their displacement. In this particular case, this will be reduced using landmarks as reference points, along with ultrasonic sensors and a control algorithm which will regulate the robot's position. Thus, the vehicle will travel it's previously defined route through the landmarks and, doing so, will also correct its direction as it moves. The validation will be done through experimental tests on flat terrain and artificial grass without obstacles. The trajectory followed by the robot resembles a square, with 3.5 meters by side. The evaluation will be based on the difference between the robot's estimated and real position. The experimental results produced an error of approximately 3 and 15 centimeters on the "x" and "y" axis respectively.