In the field of Global Navigation Satellite System (GNSS) attitude determination, the constraints usually play a critical role in resolving the unknown ambiguities quickly and correctly. Many constraints such as the baseline length, the geometry of multi-baselines and the horizontal attitude angles have been used extensively to improve the performance of ambiguity resolution. In the GNSS/Inerti...

Hardware and software architecture of a novel spacecraft Attitude Determination and Control System (ADCS) based on smartphones using Variable Speed Control Moment Gyroscope (VSCMG) as actuator is proposed here. A spacecraft ground simulator testbed for Hardware-in-the-loop (HIL) attitude estimation and control with VSCMG is also described. The sensor breakouts with independent micro-controller ...

A method for relative attitude determination from planar line-of-sight observations is presented. Three vehicles are assumed to be equipped with sensors to provide measurements of the three inter-vehicle line-of-sight vectors. The line-of-sight vectors are further assumed to be always in the same plane. This information is combined with all the available measurements to find an optimal relative...

This paper presents the summary of the image processing of a vision-based three-axis attitude determination sensor, which observes a solar system oblate body such as a planet or a planet’s moon. From the observed image it is possible to extract two independent directions and, consequently, to estimate the three-axis spacecraft attitude. By measuring two independent directions, the sensor can op...

The optimal attitude estimate is often defined as the solution to a minimization problem. When the objective function of the minimization problem is quadratic in the attitude matrix or equivalently quartic in the attitude quaternion, for example, in GPS attitude determination, gradient-based iterative algorithms are usually used, which can only find the local minimizer. A novel numerical method...

SIS is a Satellite controller Integrated with Star sensors, which has been developed as a prototype model of a compact, low-cost satellite controller. SIS integrates attitude sensors into a star sensor and integrates several electronics for star identification, attitude determination, attitude control, and data handling into a single processing unit. SIS meets high reliability requirements by a...

For the improvement of accuracy and better faulttolerant performance, a global position system (GPS)/vision navigation (VISNAV) integrated relative navigation and attitude determination approach is presented for ultra-close spacecraft formation flying. Onboard GPS and VISNAV system are adopted and a federal Kalman filter architecture is used for the total navigation system design. Simulation re...