Plumis; CubeSat Design Challenge Submission by Connor Tinker

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Plumis, this CubeSat challenge entry, was designed by a high school Junior named Connor Tinker. Because of the GrabCAD challenge regulations, it is being submitted by the student's father, Richard Tinker. -Lightest CubeSat ever recorded -Utilizes DMLS or SLS manufacturing processes, and 3 different metal based material options (Including two never before used on CubeSats) -Modular design with various adjustable mounting holes -Over 900,000 mm^3 of space for test equipment -Can withstand common 60G's created by rocket motor vibe, and up to 150G's with negligible deformations. -Simple two part body utilizing stock parts, and low cost materials to improve value Plumis is the result of a month of research, and design, put through a collaboration between mechanical and aerospace engineers from The Johns Hopkins University Applied Physics Laboratory, and Google, mentoring a high school student pursuing mechanical engineering. The name Plumis comes from the latin word for feathers, and reflects this designs groundbreaking innovations. Plumis is designed to be the worlds lightest CubeSat structure ever made, with a frame weighing in at only 84g. With over 900,000 milimeters cubed of storage space, this design allows for researchers to safely send large heavy test equipment into the very depths of space at a low cost. The second design objective of Plumis was to make it robust, and environmentally flexible. From the mass equivalence launch load curve, we determined that the largest forces a CubeSat would undergo (due to rocket motor vibe) are 60G's. According to design simulations, Plumis can withstand these forces with negligible deflections and only 4.9 MPa of Von Mises Stress at certain frame locations. As CubeSats become more common, and less expensive, more varieties of research will be performed using these structures. Currently, CubeSats are launched no further than L2 orbit (Lagrangian orbit), for data transfer technology used on research budgets cannot send information across any longer of a range. But, as data technology becomes innovated (with it will, exponentially), researchers will want to send their satellites deeper into space, to take new, groundbreaking measurements. Space itself is only 3 Kelvin, or -270 degrees Celsius. Radiation and planetary albedo can make testing environments a cool 25 Kelvin, or -250 degrees Celsius. This means that in order to innovate, and change the way we design and manufacture CubeSat structures, we must take into account the conditions which our research will later be taken in. FDM, or Fused Deposited Manufacturing, is an amazing, accessible manufacturing technology: But will not work effectively for this design, and may not work for any CubeSat design. FDM relies on the ability to give parts a less than 100% infill, thus creating air pockets. Even at 100% infill, machine inconsistencies can give FDM parts small air pockets. In the vacuum of space, these air pockets will be torn apart, fracturing any structure until failure. In addition, FDM traditionally uses plastics only. Very few plastics can withstand cryogenic conditions, and the ones which can are too dense and soft for structural applications. Plumis avoids these issues through the use of DMLS, and SLS additive manufacturing. Plumis has the potential to be made of three different materials, (two never before used in CubeSats), all of which can sustain structural integrity in cryogenic conditions. Plumis has two parts, with a set of 4 stock part rails in order to comply with CubeSat design specifications, while still keeping the price down. The simple design includes a main frame, and a bottom plate. The bottom plate can be removed through 4 metric fasteners and National Aerospace Standard (NAS) lock-nuts. All panels of Plumis contain M2, M3, and M4 adjustable mounting capabilities to improve the designs adaptability. Please see the powerpoint presentation in the renderings, or online via google drive. This includes even MORE details about Plumis, how we came to this design solution, and what research we used to back up our decisions. Powerpoint Link: https://docs.google.com/presentation/d/1ZJwug01bAYsroUv8VkhJHYkDPo2o7SaFCVbIDRoys7Y/edit?usp=sharing Reminder: This design was created solely by Connor Tinker, under the advice of professional mechanical and aerospace engineers from JHU APL and Google. This design was submitted by Richard Tinker in order to comply with CubeSat design challenge regulations (Must be 18 years of age). Connor is a student at River Hill high school with 6 years of CAD experience. Connor was a student in FIRST Robotics for 7 years, and has been an intern at the Johns Hopkins University Applied Physics Laboratory for the past year. At APL. Connor works on projects contracted by the MDA, NASA, and US Navy. Connor is the founder of a non-profit called Thrive, and the founder/mentor of the Society of Women Engineers (SWE) at APL FIRST Tech Challenge Robotics Program. Connor plans to study mechanical and aerospace engineering, and has not yet committed to a school. All comments, suggestions, and updates will be shared with Connor!