NASA Challenge Model Antonio G. Salazar Martín

grabcad

UPDATE August 23, 2018I added some new animations (in gif, avi and mp4; folder: Animations). Please, note that some new animations are not visible in the library. The complete new animation is also in YouTube (https://youtu.be/uoorVftBJCk). I also modified some parts (see folder: Modified Parts, New Renderings), such as the Robot_Tool_5, to improve the velocity of the process. This new configuration enables to apply the Avcoat material in a faster way. In general, the process enables to speed up the current process. Everything that was in the task has been included. If you have any comments or doubts, please, do not hesitate to contact me.FIRST ENTRY August 9th, 2018This is my entry for “NASA Challenge: Human Rated Spacecraft 3D Printing Process Animation”. I strongly recommend seeing the renderings, the video and the poster first. I attached the following documents or folders:CAD files: Full_Model_Assembly (Folder, Solidworks files), Full_Model_Assembly_STEP (Folder, STEP files), Full_Model_Assembly_STL (Folder, STL files), Full_Model_FBX (Folder, FBX files), Full_Model.zip (Solidworks files).Images: Renderings (Folder).Animation: NASA_CHALLENGE_SALAZAR.mp4 (due to the model geometry and some characteristics of the animation, and since one of the jury said that you accept this kind of file, I decided to submit the animation in mp4).Poster: NASA_CHALLENGE_SALAZAR.pdf.VIDEO TRANSCRIPTWelcome. In the following video I’m going to show you my envisioned concept of manufacturing the spacecraft protection heat shield and the pressure vessel of the Orion spacecraft. This model fulfils the technical requirements placed by the National Aeronautics and Space Administration in the Grabcad Community.This model not only shows the additive manufacturing process of both the thermal protection heat shield and the pressure vessel, but also offers a concept of how assembly and store the different parts of the Orion capsule. Regarding the additive manufacturing methods used, two different technologies were chosen. For the metal spacecraft pressure vessel structure, selective laser melting technology was chosen since it provides better results in dimensional accuracy, surface finish and mechanical behaviour compared to other additive technologies when manufacturing metal parts. Through this technology, powder metal such as titanium, cobalt chrome, aluminium or stainless steel and their alloys are used as raw materials. By exporting the object design as a three-dimensional computer-aided design data to the selective laser melting software, the faceted model is then mathematically sliced into a series of parallel cross-sections, creating a machine transverse path for each layer, usually from twenty to one-hundred micrometres thick. In this technology, thin layers of atomized metal powder are distributed using a coating mechanism onto a tray, which moves along the vertical axis. The metal powder is then fused by a laser beam that moves along the horizontal axis. Laser energy should be intense enough to enable full melting of the metal powder. All this process takes places inside a chamber with a controlled atmosphere of either argon or nitrogen gas. In this process, the robotic arms are used to remove the material powder not used during the selective laser melting process. If it’s required, different manufacturing tools can be used, such as welding, broaching or boring for final machining. The X-ray system can be also attached to the robot in order to carry a surface analysis.For the thermal protection heat shield, two robotic arms perform the printing of the composite material using different printing heads. In this case, the fused-deposition modelling technique, also known as fused-filament fabrication, is chosen. In the fused-deposition modelling process, a feedstock filament of the raw material on a spool is fed into the extrusion head with the aid of a tractor wheel arrangement through generating extrusion pressure. The movement of the extruder by a numerical control-based code, coupled with the extrusion of a semi-molten filament above the material’s glass transition temperature, enable the production of the desired geometry. Because the semi-molten extruded material is deposited on the previously laid layer, which is still hot, both filaments of material are joined through the local sintering process of neck growth. The idea of this concept is firstly to produce a thin metal layer part using the selective laser melting technology, with the shape of the Orion’s protection heat shield, and then print the honeycomb matrix with fused-deposition modelling technology. Then, with a different extrusion head, the Avcoat, an epoxy novolac resin, is then gunned into each cell individually.The assembly of the different work-in-process products are done over the selective laser melting machine.Regarding the distribution, rail guided on-the-floor powered vehicles are used to move different equipment. The material storage, mixing tanks, compressors and filament feed systems of both additive technologies are in the first floor. In the second one, raw parts and materials, work-in-process and finished products are stored. The additive manufacturing processes are carried in the third floor. Elevators in both sides of the building and a superior crane are used to move the products in the vertical direction. The main idea of this distribution concept is to have a factory completely automated with flexible manufacturing systems and a minimum manual maintenance.Last, but not least, thanks for watching this video and also to the National Aeronautics and Space Administration and Grabcad for offering this opportunity.