A General Approach to the Shaded Sun Sensor Modeling Problem with an Application to the FLTSATCOM Shaded Sun Sensors.
Abstract
Sun sensors are widely used in space vehicles for sun acquisition or determination of body attitude relative to the sun. In order to alleviate undesirable reflections from the various parts of the vehicle, shades are often introduced about the sun sensitive device. The added nonlinearity in the attitude control system due to the effect of shading alters the stability margin and degrades the analytical results obtained from the linearized approach. A general approach is presented in this paper on the modeling of shaded sun sensors. The approach applies to shading wall geometry and solar cells whose boundaries can be described or approximated by a piecewise linear relation. The output of the cell, which depends on the sun angle and the shade dimensions, is a function of the intersection of the shade pattern with the cell area. Having defined the shade structure by vectors fixed in the sensor's coordinate frame, the shade contribution due to each partitioned shade structure is calculated sequentially so that it is not necessary to define an integral shade pattern and various boundary conditions.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 25, 1975
- Accession Number
- ADA016529
Entities
People
- K. K. Wong
Organizations
- The Aerospace Corporation