Despite the huge technological progress in digital control systems during the last decade, the problem of disabled people assimilating in modern society is still relevant due to the outdated technology in this area. One of the examples is the movement of visually impaired people. Nowadays, they use a white cane as a primary tool for interaction with the environment. The problem with this traditional technology is that the white cane does not give enough information about surrounding objects. Thus, the main modifications of the white cane would consist of integrating the obstacle detection system based on ultrasonic sensors, and informing the user by audio signals. The obstacle detection system is consist of a number of ultrasonic sensors located at different angles. Thus, they measure the distance from the cane to the ground. The data collected from the sensors, is analysed for three types of terrain: flat ground, small pit or hole, and stairs. In the case, when the sensors' reading does not match with the reading from the flat ground, the system will alert the user by the audio signal.