Jan Stupl (SGT / NASA Ames Research Center), Jonathan Aziz (University of Colorado Boulder / NASA Ames Research Center), Bron Nelson (Computer Sciences Corporation/NASA Ames Research Center), Fan Yang Yang (STC/NASA Ames Research Center), Cyrus Foster (SGT/NASA Ames Research Center), Nicolas Faber (SGT/NASA Ames Research Center), Andrew Nuttall (Standford University/USRA/NASA Ames Research Center), Chris Henze (NASA Ames Research Center), Creon Levit (NASA Ames Research Center)
Keywords: space debris mitigation, conjunction analysis, laser, parallel computing
Abstract:
This paper provides an updated efficiency analysis of the LightForce space debris collision avoidance scheme. LightForce aims to prevent collisions on warning by utilizing photon pressure from ground based, commercial off the shelf lasers. Past research has proven that a few ground-based systems consisting of 10 kW class lasers directed by 1.5 m telescopes with adaptive optics could lower the expected number of collisions in Low Earth Orbit (LEO) by an order of magnitude. Our simulation approach utilizes the entire Two Line Element (TLE) catalogue in LEO for a given day as initial input. Least-squares fitting of a TLE time series is used for an improved orbit estimate. We then calculate the probability of collision for all LEO objects in the catalogue for a time step of the simulation. The conjunctions that exceed a threshold probability of collision are then engaged by a simulated network of laser ground stations. After those engagements, the perturbed orbits are used to re-assess the probability of collision and evaluate the efficiency. This paper describes new simulations with three updated aspects: 1) By utilizing a highly parallel simulation approach employing hundreds of processors, we have extended our analysis to a much broader dataset. The simulation time is extended to one year. 2) We analyze not only the efficiency of LightForce on conjunctions that naturally occur, but also take into account conjunctions caused by orbit perturbations due to LightForce engagements. 3) We use a new simulation approach that is regularly updating the LightForce engagement strategy, as it would be during actual operations. In this paper we present both our simulation approach to parallelize the efficiency analysis, its computational performance and the resulting expected efficiency of the LightForce collision avoidance system.
Date of Conference: September 9-12, 2014
Track: Orbital Debris