# ReDSHIFT: A Global Approach to Space Debris Mitigation
In order to properly exploit the solar radiation pressure driven resonances, the use of area augmentation devices is studied in detail. The main results on this subject are outlined in Section 2. Furthermore, an extensive campaign of long term simulations of the space debris environment was performed (see [1]) with a twofold aim. First, to identify and quantify the benefits of the proposed solutions. Second, to characterize the particle flux impacting on a spacecraft under different future scenarios with the aim of evaluating the effectiveness of the shields designed in the experimental part. From the astrodynamics results, several engineering requirements are derived for the area augmentation devices to be included in the spacecraft design, with the aim of achieving an effective deorbiting of the satellite at the end-of-life. The compatibility of these devices with the 3D printed spacecraft (described in Section 3) is also analyzed within the project. Moreover, the re-entry trajectories of the objects deorbited through the \"deorbiting highways\" (both with and without the area augmentation devices) are studied to characterise the behaviour of the spacecraft in terms of Design for Demise (D4D) when interacting with the atmosphere. These information will, in turn, be transferred to the design phase to identify materials and 3D printed structures that are not going to survive the re-entry phase. The experimental pillar is mainly devoted to the design and production of a novel spacecraft by 3D printing. In fact, in an effort to make novel technological solutions easier and more attractive to produce and to implement into future design, thus enhancing the debris-oriented vision of spacecraft manufacturing, ReDSHIFT will explore the possibility to use the now blossoming additive manufacturing technology, to actually realize a model spacecraft and, in particular, some specific parts related to the debris mitigation issues, such as, e.g., the shielding, a sail canister, the sail hatches and joints, etc. As mentioned above, the characteristics of the sail will also be dictated by the needs emerging from the dynamical studies. Innovative shielding against small particles was studied and shall be directly embedded in the aluminum printed spacecraft structure. The materials and components of the spacecraft were tested for D4D in a heated wind tunnel. The D4D tests also included an unprecedented test on an engineering model of a reaction wheel. The first prototype spacecraft (an 8-unit CubeSat) is now in the production phase and will be tested (including launch vibration tests) in the late spring. Based on the results of the first testing phase an improved design, expressly tailored to the 3D printing peculiarities, will be performed and the final ReDSHIFT prototype will be printed in the second half of 2018. The final 3D printed spacecraft will be a fully tested prototype of a small satellite, expressly designed having in mind the space debris issues and regulations. From this prototype a fully functional specimen could be produced with limited additional effort, paving the way to significant innovation in the field. The main results of the experimental branch of the project are outlined in Section 3. The results of the dynamical mapping and the demisability analysis are then integrated into a software tool that shall help the users to conceive a \"debris compliant\" space mission from the design to the disposal phase encompassing all the above findings. This powerful tool is briefly described in Section 4. Finally, the possible improvements to the international space regulations and standards, stemming from the project's findings, are analyzed and outlined in Section 5. As already mentioned above, it is worth stressing again that this paper is presenting the main results of ongoing research activities within a project encompassing 13 research units.