This paper describes the driving control system of a powered wheelchair using voluntary eye blinks. Recently, new human computer interfaces (HCIs) that take the place of a joystick have been developed for people with disabilities of the upper body. In this study, voluntary eye blinks are used as an HCI. However, the problem with this HCI is that the number of input directions and operations is smaller than that of a joystick, which causes inefficient movement. Therefore, assist systems are needed for efficient and safe wheelchair movement. This paper presents the system which is based on environment recognition and fuzzy theory. It can detect obstacles and passages in a real environment, and the velocity and direction are calculated automatically for obstacle avoidance or right/left turns. Simulations show the effectiveness and robustness for the driving position and position where an operation input is given. Furthermore, experiments were carried out and verified the effectiveness of the proposed method.