Path: SC/Sensor
% A dual scan Earth Sensor model This function models a dual scan earth sensor. It has two sensors at different roll angles. It measures the chordwidth given by the two scans and then uses that to compute roll and pitch. The offset of the scan from vertical axis determines pitch. It also computes a standard, the average of the two so that if one scan is off the Earth it can still produce roll and pitch angles. It updates d each time it is called. The standard chord is updated sequentially wih each sample. Type PlanetSensorDualScan for a demonstration of a spacecraft in geosynchronous orbit. -------------------------------------------------------------------------- Form: d = PlanetSensorDualScan; [roll, pitch, d] = PlanetSensorDualScan(r, q, d) -------------------------------------------------------------------------- ------ Inputs ------ r (3,:) Position vector in the ECI frame (km) q (4,:) Quaternion ECI to Body d (.) Sensor data structure .cant (2,1) Cant angle from rotation axis (rad) .sC (1,1) Standard chord (rad) .uB (3,1) Boresight vector .uS (3,1) Scan vector .aP (1,1) Planet radius .sig (1,1) 1 sigma chordwidth noise .useScan (2,1) true if use that scan .valid (1,:) true if data is valid ------- Outputs ------- roll (1,:) Roll (rad) pitch (1,:) Pitch (rad) d (.) Sensor data structure --------------------------------------------------------------------------
AerospaceUtils: Coord/RollPitchToQECI Orbit: OrbitMechanics/RVOrbGen Common: Graphics/Plot2D Common: Quaternion/QForm Math: Linear/Cross Math: Linear/Mag Math: Linear/Unit
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