Optimization of Reconfigurable Satellite Constellations Using Simulated Annealing and Genetic Algorithm

Abstract

Agile Earth observation can be achieved with responsiveness in satellite launches, sensor pointing, or orbit reconfiguration. This study presents a framework for designing reconfigurable satellite constellations capable of both regular Earth observation and disaster monitoring. These observation modes are termed global observation mode and regional observation mode, constituting a reconfigurable satellite constellation (ReCon). Systems engineering approaches are employed to formulate this multidisciplinary problem of co-optimizing satellite design and orbits. Two heuristic methods, simulated annealing (SA) and genetic algorithm (GA), are widely used for discrete combinatorial problems and therefore used in this study to benchmark against a gradient-based method. Point-based SA performed similar or slightly better than the gradient-based method, whereas population-based GA outperformed the other two. The resultant ReCon satellite design is physically feasible and offers performance-to-cost(mass) superior to static constellations. Ongoing research on observation scheduling and constellation management will extend the ReCon applications to radar imaging and radio occultation beyond visible wavelengths and nearby spectrums.

Automated Design of CubeSats using Evolutionary Algorithm for Trade Space Selection

“…The exposed solar panel area is done in two steps. First for each panel having an area A p and unit normal vectorn p and the body-to-sun unit vectorr s/b , the projected area of each panel on a plane perpendicular tor s/b is given by Equation (11) and shown in Figure 7a.…”

“…Other work includes design optimization of a power subsystem [5], low-thrust orbit transfer [6], spacecraft structure [7], and a corner retroreflector for satellites [8], which has shown potential improvements over traditional methods. An evolutionary approach has also been applied to design satellite constellations for continuous regional coverage [9], nontraditional constellations such as heterogeneous and rideshare constellations using COTS components to increase resiliency and responsiveness [10], reconfigurable satellite constellations [11], regional navigation satellite system constellations [12], pattern forming tasks using robot teams [13] and even teams of excavating robots for lunar base preparation [14], which have produced human-competitive designs. This process has also been successfully applied to the design of mobile robots [15] and water desalination systems [16].…”

Sun-synchronous repeat ground tracks and other useful orbits for future space missions

“…Examples of the last category of solar observatory spacecraft include Yohkoh (Solar-A), Hinode (Solar-B) and Transition Region and Coronal Explorer (TRACE). In lieu of riding the terminator, a Sun-synchronous satellite may be in a noon/midnight orbit or have any MLTs as scientific requirements may dictate (10,11) . Figure 2 depicts a few SSOs that have different MLTs but all the same nodal regression rate, 360 • /365.2422day = 0.9856 • /day or 2 × 10 −7 rad/s (12) .…”

“…And for simplicity, circular orbits will be considered throughout this paper. Substitution of e = 0 into Equations (8) and (9) leads to Equations (11) and 12, respectively. Note also that semi-major axis (a) has been replaced by the sum of the Earth's radius (R E ) and height (h) to calculate altitude directly.…”

“…Although the MSSRGT orbits achieve Sun-synchronism less frequently than SSRGT orbits, the former provides more coverage to near-equatorial regions due to In order to compare the coverage performance of two types of orbits, we should consider both the individual satellite design (e.g. sensor boresight angle) and the overall constellation geometry (11) .…”