When devices and applications provide assistance to people they become part of assistive technology. If the assistance is given to impaired people, then it is possible to refer those technologies as adaptive technologies. The main aims of these systems are substitution of physical assistants and the improvement of typical tools already available for impaired people. In this paper some bene ts and examples of adaptive technology applications will be discussed. Moreover we present an adaptive technology framework to avoid obstacles to be exploited by visually impaired and blind people. The proposed assistive technology has been designed to perform vision substitution; specifically it provides Electronic Travel Aid (ETA) capabilities through the processing of information acquired with a depth sensor such that the user can avoid obstacles during the environment exploration. In the proposed system we require to know just the height of the sensor with respect to the ground floor to calibrate the ETA system. Experiments are performed to asses the proposed system.