Propellant-less steering law for small satellites orbital decay mitigation using drag and solar radiation pressure

Abstract The growing demand for low-cost, versatile small satellites in Low Earth Orbit (LEO) has significantly increased orbital traffic, amplifying the challenge of sustaining satellite missions without onboard propellant. These satellites are often deployed in orbital regimes where atmospheric Drag and Solar Radiation Pressure (SRP) constitute the main non-conservative forces, often of comparable magnitudes. Non-propulsive control techniques leveraging aerodynamic forces and SRP offer promising alternatives for maintaining and adjusting satellite orbits. This paper introduces a propellant-less steering law that exploits Drag and SRP forces to mitigate orbital decay, optimizing satellite orientation to minimize cumulative deceleration effects. The proposed approach calculates the optimal cross-sectional area for Drag and SRP influences, effectively reducing orbital decay. Applied in simulations to ongoing small satellite missions under simple operational constraints, the method demonstrates notable decay reduction compared to historical mission data. Finally, this paper presents a Flight Envelope that details the potential reductions in orbital decay achievable for various classes of small satellites in LEO, with special emphasis on Very Low Earth Orbit (VLEO) and the transition to higher altitudes. The analysis considers critical parameters including altitude, satellite shape, and orbital geometry. This framework offers vital insights for both mission planning and vehicle design in these challenging orbital regimes.