In this paper, we propose software architecture of behavioural-based robot control system using Active Object Computing Model. Active Object Computing Model is a programming technique that combines the three components, Event Driven Programming paradigm, Event Driven Software Architecture and UML State chart formalism. The scope of this project includes the activities of designing and implementing behavior-based navigation system software, designing and building autonomous mobile robot for software implementation, testing, observing and analyzing the behaviour of autonomous mobile robot which is controlled by behaviour-based navigation system software. The software has been tested on an autonomous mobile robot and run on ARM Cortex M3 processor using mbed NXP LPC1768 microcontroller and successfully demonstrated the behaviour of obstacle avoidance and object Following. Software Architecture is built using Quantum Platform™ from Quantum Leaps.