Development of a system for teaching CS1 in C/C++ with Lego NXT robots.

Abstract

This paper describes the development of a system for teaching C/C++ using a LegoTM NXT in a CSI college course on introductory programming. The programming of the NXT robot has been implemented using a C/C++ cross-compiler, which generates code that runs on an Open Source firmware platform, nxtOSEK. The system has built in commands and objects that run the motors and receive information from the sensors that are on the robots. The cross-compiler has been embedded in an Open Source Integrated Development Environment (IDE) Code::Blocks. The programming environment for the NXT has evolved from a previous development using the LegoTM RCX and has the advantage that it utilizes a Bluetooth interface, while the RCX uses a tower based infrared communication device. The NXT is more reliable and can be programmed to pair a specific interface with a particular robot, so that there is no cross-talk when different robots are utilized in a classroom setting. The IDE and robotic software executes on a virtual machine running under the freely available software, SunTM VirtualBox. This allows for a uniform programming platform for Windows, MacOS, and Unix/Linux. The use of robots in CS1 affords science and engineering students the opportunity to learn sensorymotor based control, to work with an IDE early in their careers, and to gain experience with development and debugging tools that can be utilized throughout the students’ academic and professional careers.