The Street to Jupiter: 20 years of trajectory optimization
by Simon Mansfield
Sydney, Australia (SPX) Aug 21, 2023
The intricate multi-body dynamic setting stemming from Jupiter and its 4 distinguished Galilean moons complicates trajectory design and optimization. Coupled with the formidable radiation surrounding Jupiter and spacecraft’s restricted gasoline, these challenges necessitate superior and complicated design options.
To bridge this hole, a joint examine by students from Nanjing College of Aeronautics and Astronautics alongside their friends at Rutgers, The State College of New Jersey, dove deep into the trajectory design and optimization strategies of the previous 20 years. Their findings, lately printed in House: Science and Know-how, present an encompassing abstract of cutting-edge methodologies regarding 4 pivotal exploration phases: capturing Jupiter, touring the Galilean moons, mapping Jupiter globally, and at last, orbiting and touchdown on a goal moon.
Jupiter Seize Trajectories
The evaluation highlighted strategies and optimization for Jupiter seize trajectories, which considerably lower the required delta-V (?v) utilizing satellite-aided seize strategies. Traditionally, single-satellite-aided seize was derived by Cline. The trendy method, as studied by Lynam et al., expands to triple- and quadruple-satellite-aided captures, which, although advanced, are extra environment friendly in decreasing ?v. Moreover, methods comparable to utilizing lengthy tethers to harness Jupiter’s strong magnetic subject or the strategy of cloudtops arrivals supply various means to effectively enter Jupiter’s orbit.
Touring the Galilean Moons
When touring the Galilean moons, the patched-conics mannequin stays the prevalent selection resulting from its simplicity in designing flyby sequences. Superior strategies just like the V-infinity leveraging maneuvering (VILM) and instruments just like the Tisserand graph amplify the effectivity of orbit maneuvers. But, there is a recognition that two-body strategies, though handy, is perhaps limiting. Therefore, newer three-body trajectory design strategies are on the rise, with AI displaying promise in fixing the historically difficult three-body downside.
Jupiter World Mapping Trajectories
The examine delves into Jupiter’s world mapping trajectories, emphasizing excessive inclination wants. Approaches like utilizing the Galilean moons’ gravity assists and designing repeating ground-track orbits underneath Jupiter’s non-sphere perturbation are spotlighted. Moreover, there is a nod to the challenges of adjusting exploration orbits that require longer flight-time transfers.
Moon Orbiter and Lander Trajectories
Discussing moon orbiter and touchdown trajectories, the authors word the suitability of low-altitude and near-polar orbits, particularly round Galilean moons. Nonetheless, challenges exist, comparable to extremely inclined orbits round Europa being unstable resulting from Jupiter’s gravitational affect. A number of options, from pure frozen orbits for moons like Ganymede and Callisto to modern mission orbits round unstable periodic orbits for observations, are explored.
The evaluation concludes by juxtaposing totally different strategies, indicating that whereas two-body strategies are environment friendly for Jovian system flyby trajectories, they may escalate gasoline prices. As compared, three-body or multi-body strategies, although intricate and time-intensive, leverage the Jovian system’s pure dynamics extra adeptly. Furthermore, low-thrust strategies, though fuel-efficient, current navigation challenges. Most trajectory optimization strategies thus far are deterministic, with strong trajectory optimization rising as a future path given its consideration of uncertainties. This complete look indicators the evolution of trajectory optimization, hinting at future breakthroughs integrating multi-body strategies, strong optimization strategies, and AI.
Beijing Institute of Know-how
The million outer planets of a star known as Sol