Abstract: An assist apparatus for a visually impaired person is provided. The assist apparatus includes an image acquisition unit including a sensor unit, a gravity sensor, at least one retractable and extendable protrusion, a motor drive, and a processor. The sensor unit acquires a depth image including a distance value for an obstacle in front of the person. The gravity sensor detects an inclined angle of the image acquisition unit in relation to a ground surface upon which the person is walking. The motor drive drives a motor to cause the at least one protrusion to extend or retract. The processor generates 3-Dimensional (3D) data using the detected inclined angle and the acquired depth image, converts the distance value into a height value, and controls the motor drive to cause the at least one protrusion to extend or retract to the height value.