The document describes a proposed human detection and obstacle avoidance algorithm for a service robot. An ARM 11-based Raspberry Pi board will be used along with a USB camera and ultrasonic sensor. OpenCV will be used to detect and track humans based on body shape analysis of camera images. The ultrasonic sensor will detect obstacles and allow the robot to avoid them while continuing to track the detected human. The goal is to allow the service robot to follow and track a human while navigating around moving obstacles in an outdoor environment.