Session
Session V: 14th Annual Frank J. Redd Student Scholarship Competition
Abstract
The application to which smaller and more affordable satellites may be employed is often constrained by the high pointing-accuracy requirements of current missions. There is therefore an increasing need to develop high accuracy attitude systems that do not breach small satellite mass and cost constraints. This paper proposes a novel method for determining attitude or rates over three axes using low cost, low mass, Earth-pointing push-broom sensor pairs. The technique is applicable to existing Low Earth Orbit (LEO) satellites with the appropriate camera systems, such as the Surrey Satellite Technology Ltd (SSTL) Disaster Monitoring Constellation (DMC) multispectral imager. The effects of attitude on satellite push-broom imagery are modelled, with inversions detailing the extraction of rates. Simulations show that using a suitable sub-pixel level registration scheme, such as Phase Correlation, with DMC imagery, attitude position accuracies in the order of a few arcminutes are achievable. Simulations have also shown pitch and roll rates of around an arcsecond per second to be measurable. Results using DMC imagery confirm the viability of using conventional, off-the-shelf, cameras onboard small satellites to determine attitude position and rates to a high level of accuracy.
Presentation Slides
High Performance Attitude Determination through Analysis of Geometric Distortions within Earth Observational Satellite Imagery
The application to which smaller and more affordable satellites may be employed is often constrained by the high pointing-accuracy requirements of current missions. There is therefore an increasing need to develop high accuracy attitude systems that do not breach small satellite mass and cost constraints. This paper proposes a novel method for determining attitude or rates over three axes using low cost, low mass, Earth-pointing push-broom sensor pairs. The technique is applicable to existing Low Earth Orbit (LEO) satellites with the appropriate camera systems, such as the Surrey Satellite Technology Ltd (SSTL) Disaster Monitoring Constellation (DMC) multispectral imager. The effects of attitude on satellite push-broom imagery are modelled, with inversions detailing the extraction of rates. Simulations show that using a suitable sub-pixel level registration scheme, such as Phase Correlation, with DMC imagery, attitude position accuracies in the order of a few arcminutes are achievable. Simulations have also shown pitch and roll rates of around an arcsecond per second to be measurable. Results using DMC imagery confirm the viability of using conventional, off-the-shelf, cameras onboard small satellites to determine attitude position and rates to a high level of accuracy.
