Sun sensor is the most widely used sensor for attitude control of artificial satellites because the Sun is a good optical source for attitude reference. In this study the design and fabrication of such known as 'Digital sun sensor' is studied. The digital sun sensor consists basically of a box with a slit on the top face, with a gray code mask placed on top of a photoelectric transducer which is placed inside the box. The sun shines through the slit at an angle Θ, making an image on the gray code. Hence the angle $\theta$ is converted to a function of the gray code position. The amplifier following each detector produces either an ON or an OFF signal depending on the pattern on the gray code mask and the sun's elevation angle. So, it produces a digitally coded output that can be used directly by the attitude determining electronics.
The reflection in the vicinity of the Al slit was the major problem of the sensor. To correct this problem, Al was ground for diffused reflection. The resolution of the sensor is about 1.2 degree and, FOV is ±30 degree. In order to fabricate more accurate sensor, we must upgrade the slit, make accurate mechanical system and, use more parallel light source.
