Real time embedded control system development for wireless mobile platforms

Abstract

MCP is the chosen acronym for Mini-Car Pro - a wireless mobile robotic platform designed for research and education in embedded system development and wireless sensor network. The hardware architecture consists of a 200 MIPS ARM9 32-bit SoC, ultrasonic sensors, an IEEE 802.15.4 based Telos mote (a wireless sensor network node) for wireless communications, and a differential motor driven base platform with shaft mounted optical encoder for closed loop motion control. MCP is controlled remotely via a console software client running on a Windows based PC. Through the graphical user interface, the operator sends motion commands to and receives status from the MCP through a pair of Telos, one connecting to the PCpsilas USB port and the other to the MCPpsilas. One of the key features of the MCP is automated obstacle avoidance empowered by on-board ultrasonic detection of the surrounding environment. To achieve the goal of real-time system control, multi-thread software architecture is adopted, and along with a real-time Linux operating system framework. This paper describes the design of the MCP, and in particular highlights the real time software engineering development aspects which are generically applicable to similar mobile robotic platforms.