جستجوی مقالات مرتبط با کلیدواژه « حسگر خورشیدی » در نشریات گروه « فنی و مهندسی »

In this paper, designing, implementation and validation of a laboratory for sun sensor test and calibration would be presented. In this laboratory, power, spectrum, uniformity, subtending angle, and the parallelism of the sunbeams and also the angular motion of sun sensor with respect to sun simulator are accurately simulated. Using the simulator, test and calibration of sun sensors in different angular maneuvering would be possible. This capability depends on a method for precise calibration of 3DOF motion simulator and sun simulator with respect together. This calibration method is used to make the sunbeams and optical axes of sun sensors, which is perpendicular to the sun sensor surface, parallel and coaxial. In the beginning of the paper, the detailed description and adjustment methods for each of the components of the simulator are presented. Afterwards, an algorithm for making the optical axes of the sun sensor coaxial with the axis of the sun simulator beams will be developed. Furthermore, each of the specifications of the produced beams is compared with the sunbeams specifications using the existent peripheral or some heuristic methods. Finally, a referenced calibrated sun sensor is evaluated in a known angular maneuver by the developed simulator. Comparing the known angular maneuver to the measured angles shows the adequate accuracy of the implemented simulator in order to test and calibration of the analog sun sensor. Considering the specification of the produced beams, it seems that digital sun sensor can also be calibrated.

Simulating environmental conditions for the satellite attitude sensors is a fundamental requirement of hardware in the loop tests of attitude determination and control subsystem. In this paper, a new design for simulating sun vector and magnetic vector is presented. The operating environment for attitude sensors is simulated using a sun simulator, a two-degree-of-freedom table for changing the attitude of the sun sensor, and a three-axis Helmholtz coil. The sensors measurements showed that with this setup, the sun and magnetic vectors can be created with an acceptable accuracy using the orbital position and the attitude of the satellite. So, the test bed can be used for attitude determination of hardware in the loop tests.

Evaluation of the satellite attitude determination system is very complicate because of need to simulate space environment on the ground. In this paper a laboratory Implementation of attitude estimation using sun sensor and magnetometer is reported.The test setup includes a sun simulator installed in a dark room. The magnetometer measures the local magnetic field. Sensors are rotated using a 2 DOF table. The reference models are adapted with the test setup. Attitude determination using classic and extended kalman filter methods is implemented by sensors data fusion. The test results verify the controlled motion of sensors in the limits of setup accuracy order.