Construction of a Low-cost Wheeled Mobile Robot for Testing Automatic Control Techniques

This paper presents the construction of a low-cost wheeled mobile robot, of the differential type, for testing automatic control techniques. The elements integrating the robot can be grouped in hardware and software. The hardware can be divided in primary and secondary one. The primary hardware refers to an Arduino UNO board and a Raspberry Pi 3 B+ single board computer, which shall execute control techniques. The secondary hardware is associated with the sensors, DC motors, power stage, and chassis of the robot. It is important to stress that hardware was selected by considering price, capabilities, features, and suppliers or distributors. In the case of the primary hardware, the elements were chosen by taking into account the programming languages that support. Hence, all the hardware elements of the robot are relatively cheap, have mid-range features, and can be easily acquired. The primary hardware supports languages as C++, Python, and Java. Therefore, free software was used to program the Arduino UNO and Raspberry Pi 3 B+ boards. Lastly, in order to validate that the proposed low-cost robot is useful to test control techniques, a trajectory tracking control is successfully implemented. The obtained results motivate authors to use the built robot as didactic material to teach science, technology, engineering, and mathematics subjects in high-school and university, with the intention of improving the skills of students.