Scheduling algorithms for rapid imaging using agile Cubesat constellations

Coordinated Motion Planning for On-Orbit Satellite Inspection using a Swarm of Small-Spacecraft

“…In [10], smallsatellites are used in formation flight to make multi-angle observations of aerosols by directing multiple satellites to point at the same location at the same time. In [11] and [12], the authors develop an algorithm for scheduling attitude slew manoeuvres, such that the number of unique images taken by each satellite is maximized. These proposed algorithms are reliant upon modern ACS technology for small-satellites.…”

“…Unlike the orbit selection algorithm, the attitude planning algorithm must be computationally tractable for real time planning on-board each servicing spacecraft. So, we structure our attitude planning algorithm in a similar way to the dynamic programming algorithm proposed for Earth remote sensing in [11] and [12]. That is, we treat each attitude trajectory as a path of pointing directions and use dynamic programming to find the path of highest reward.…”

“…where f (p i,t , p j,t+Tint ) is simply the new information gain acquired from inspection action u ij , as defined in Eqs. 3and (11). In this case, u ij is the inspection action from time t to t + T int that moves from pointing at p i and settles at p j .…”

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

“…The first variation we can apply on SSRGTs is to allow the migration of ground tracks in a controlled way at a predefined speed. Such characteristics could be useful for tracking mobile targets when dynamic scheduling of sensor pointing may be more challenging than static targets (17) . In an SSRGT orbit with an RGT ratio of 15 and an altitude of 561km, a satellite returns to the starting location every day after 15 revolutions.…”

“…Bio-optical reflectance of coastal waters is characterised by local hydrographic features and phytoplankton composition that depend on lunar tides. It is also an active area of research because accelerating climate changes and increasing sea levels are causing impacts on estuaries and coastal regions whose vast scales could best be studied with satellite remote sensing (17,23) . Tidal synchronous orbits (TSOs) are obtained by replacing the Earth's spin rate ω E in Equation (5) with the Moon's rotation rate around the Earth ω EM .…”