Speaker
Mrs
Roxana Larisa Andrisan
(DEIMOS Space)
Description
The future sustainability of the near Earth environment requires continuing efforts to increase our knowledge of the current and future debris population. Possible on-orbit fragmentation events are a major concern nowadays. The Fragmentation Event Model and Assessment Tool (FREMAT) project for ESA was carried out with the objectives of simulating on-orbit fragmentations, assessing their impact on the space population and evaluating the capability of identification of fragmentation events from existing surveillance networks.
In the frame of the FREMAT activity, the implementation of several algorithms related to on-orbit fragmentation events was carried out. FREMAT encompasses three individual tools: Fragmentation Event Generator (FREG), Impact of Fragmentation Events on Spatial density Tool (IFEST) and (Simulation of On-Orbit Fragmentation Tool) SOFT.
Fragmentation Event Generator (FREG) has been conceived to simulate fragmentation events ( explosion and collisions). A breakup model based on recent models was the baseline for this tool .We have enhanced the baseline NASA break up model, in order to ensure the consistency of mass and momentum in the created fragment clouds. Its output is one or two clouds of fragments that can later be fed into IFEST or SOFT, or to any other propagator.
The second tool, IFEST (Impact of Fragmentation Events on Spatial density Tool) allows the evaluation of the impact of on-orbit fragmentations in the space debris population. This tool employs a fast semianalytic propagator for computing the long-term evolution of the clouds of fragments (up to hundreds of years) obtained from FREG, and computes the spatial density caused by those fragments as well as the percent increase in the background spatial density obtained from MASTER. The computation of the spatial density within this tool is validated against results provided by Esa’s POEM tool.
Finally, the third tool, SOFT (Simulation of On-Orbit Fragmentation Tool), has been created to simulate the determination of the type of fragmentation and the objects involved in a fragmentation event when a space surveillance network detects a number of unexpected new objects and a fragmentation event is considered a possible cause. It can process a cloud from FREG, and clouds from other sources can be adapted to be processed by SOFT. Uncertainties in the knowledge of the orbits of the fragments and the presence of foreign objects is also considered. . The tool determines the type of fragmentation, calculates the time and location of the event and identifies the parent objects.
This paper presents a description of the algorithms implemented in this toolkit, a brief description of each tool and a brief summary of their main functionalities. Furthermore, study cases are presented including parametric analysis by means of introducing variations in the input parameters of the fragmentation model. Short and long-term evolution of the clouds are studied, as well as the feasibility of determining the location and time of the fragmentation event. Additionally, the influence on the increase of collision risk is assessed.
| Applicant type | Co-author |
|---|
Primary author
Mrs
Roxana Larisa Andrisan
(DEIMOS Space)
Co-authors
Mrs
Alina Ionita
(DEIMOS SPace)
Mr
Fernando Pina caballero
(DEIMOS Space)
Dr
Holger Krag
(ESA)
Dr
Noelia Sánchez-Ortiz
(DEIMOS Space)
Mr
Raul Dominguez Gonzalez
(DEIMOS Space)
