An autonomous mobile robot is supplemented with intelligence in order for the perception of its environment to detect obstacles in the path of its movement and move around in an unknown environment to reach the target by avoiding the obstacles. There are two approaches like model-based and sensor-based approaches for obstacle avoidance. In this work, an obstacle avoidance mobile robot is implemented using Arduino and ultrasonic sensor with distance monitoring using PLX-DAQ tool. The mobile Robot designed which can detect obstacles in its path using a rotating ultrasonic sensor and the robot can reach the target without making any collision with obstacles. The robot with rotating ultrasonic sensor perceives the environment in three directions and detects obstacles. The ultrasonic sensor mounted on the robot can rotate from 0 degree to 180 degrees(left to right) with the help of a servo motor and find a obstacle free route by measuring distance between obstacle and robot on its left side, right side and front side of robot. The robot turns left, right or goes forward automatically depending upon the side at which there is no obstacle or a path of obstruction which is at a greater distance from the robot. The distance measured by ultrasonic sensor in three directions will be sent by Bluetooth using PLX-DAQ tool and distance will be displayed on computer with action taken by robot.