21st of March, 2019
DRAMA (“Debris Risk Assessment and Mitigation Analysis”) is a tool intended to support spacecraft system designers and operators to prove the compliance of their spacecraft with the applicable regulations, by providing estimates of the risk for ground population induced by a given satellite and the fragments generated during the re-entry at the end of its operational life. ESA’s Space Debris Office decided to carry out the upgrade of the “Debris Risk Assessment and Mitigation Analysis” (DRAMA available for download at https://sdup.esoc.esa.int/drama/) software suite implementing up-to-date methods as well as innovative and unique functionalities.
SESAM Module of DRAMA, in particular, produces a simulation of a satellite re-entry in the Earth’s atmosphere including its fragmentation and the trajectories of the fragments produced. Surviving fragments that reach ground are identified and are the input for the risk estimation (SERAM Module). As part of the DRAMA upgrade, SESAM module has been upgraded by DEIMOS Space, being subcontractor of HTG under an ESA contract. This new SESAM module has been presented in the paper “Upgrade of ESA’s Debris Risk Assessment and Mitigation Analysis (DRAMA) tool: Spacecraft Entry Survival Analysis Module” (see https://authors.elsevier.com/c/1YlCX_29e7~CiG) explaining the multiple new capabilities introduced in code as well as their effects in the re-entry process running some test cases.
SESAM has been rebuilt from scratch and its object-oriented approach has been taken one step forward leading to a more realistic modelling of the spacecraft breakup/fragmentation process. This process is no longer being forced to be a single event (fixed at a pre-defined altitude) anymore; now it is the results of the evolution of the new “connected to” and “included in” relationships defined between the primitives.
Even considering that the upgraded SESAM module follows the object-oriented approach, the innovative functionalities implemented give the upgraded DRAMA tool more flexibility and the possibility to deal with more complex spacecraft definitions and re-entry problems than the former version. Moreover, it’s possible to state that the upgraded version presented within the aforementioned paper is half-way between object- and spacecraft-oriented tools, possibly being the first example of a new type of multiobject oriented tool (MOOT).
It is concluded that the upgraded DRAMA tool is a more powerful tool designed to better aid the mission designers to successfully assess and verify the current survivability and risk requirements.
From an explosion at 100 km of altitude 60 fragments are generated, of which 10 reach the ground posing risk to human.