Abstract:

The use of Robotics as a teaching tool to foster knowledge in Science, Technology, Engineering and Mathematics – STEM for high school students is growing. Within this context, the need for solutions that decreases the overall cost of hardware is mandatory. In this work, an android-based mobile robot that allows the connection of a smartphone to different robot “bodies” composed by different hardware (Arduino, LEGO, etc) is proposed, targeting mainly high school students. The mobile platform was built using 3D printed parts and uses an Arduino board to control the servos used for the locomotion. To communicate with the Android application, a Bluetooth module is also used. The android application takes advantage of the smartphone camera and has some pre-implemented image processing modules, allowing actions such as colored line following, color proximity detection and colored object tracking. Another import feature present in the Android application is its coding capability, thanks to an embedded code interpreter. This feature was implemented using Beanshell, a lightweight script interpreter for Java. It allows writing scripts in Java programming language, which are then executed by the robot. This interpreter also provides a way for the user to write a set of instructions that defines the behaviour of the robot, primarily by checking the current status of the sensors and the smartphone camera, and manipulating the velocity of the motors.

All of the necessary components (3D source CAD + STLs) of the mobile platform presented here are available online for anyone that pretends to recreate a replica of the robot body. A detailed list of electronic components and its connections is also provided, as well as the Arduino source code along with the installation file needed for the Android application.

The high school students are then challenged to solve classical robotics tasks like line following, obstacle avoidance, and using the virtual sensors to create new challenges.

By providing this set of tools (Android app, source code, 3D CAD models, documentation, etc) it is expected to promote knowledge and develop enthusiast students in multiple fields, such as mechanical designing, electronics designing, mathematics, coding, etc. (in short, all the relevant STEM areas).

Finally, a general analysis of the usability, interoperability and feature extension capacity is made, always taking into consideration the educational purposes of this work.

Keywords:

Open-source hardware, Android, Arduino, smartphone, mobile robotics, educational robotics, STEM, open-source software.