This proposal is for a flexible navigation system for deep space operations that does not require GPS measurements. The navigation solution is computed using an Unscented Kalman Filter that can accept any combination of range, range-rate, planet chordwidth, and angle measurements using any celestial object. The UKF employs a full nonlinear dynamical model of the orbit including gravity models and disturbance models. The filter will estimate both states and parameters. The integrated system employs a sensor measures solar chordwidths and angles between planets, stars and the sun vector. The proposed sensor is is called the Twin Quad Sensor (TQS). Two independently gimbaled telescopes each with a zoom lens comprise the sensor. The sensor includes redundant processors and data networks to provide a high degree of fault tolerance in a single package. The focal plane of each telescope uses four 256 by 256 pixel arrays. These are used to measure the chord width of the Sun, angles between planets and angles to stars. In addition each telescope can be used independently and the angles between planets or to stars can be measured by high accuracy angle resolvers.
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