High-Level Project Summary
The safe release of devices in space continues to be a critical area of space innovation. Today, most devices employ pyrotechnics to facilitate the separation process, and thus produce an incredible amount of shock and material residue. Our challenge was to design a release device that operates without pyrotechnics, fits a volume similar to a household battery and does not destroy itself upon activation. For such a design to be successful, it would need to be able to maintain structural integrity and functionality in the extreme conditions of space as well as the myriad of harsh forces involved in spacecraft deployment.
Link to Project "Demo"
Link to Final Project
Detailed Project Description
Our project is a revolutionized HDRM (Hold Down Release Mechanism) called the Umbra Wave-Lock. It will provide spacecraft with an auto-releasing mechanism to detach bolts in a manner that is not destructive or shock-inducing. There are a variety of applications where it could provide value such as initiating the unfolding event of a satellite or releasing space equipment. The Wave-Lock houses a self-contained, electrically actuated mechanism that is able to reset as easily as it was activated.
A Maxon brushless DC motor will be used as input power for our device. Several electrical motors from this company are already deployed on Mars to power things such as the Ingenuity Helicopter and Perseverance Rover [1]. We will be incorporating this same motor into our design as it’s already been proven to withstand the shock on launch as well as the frigid temperature conditions in space.
Converting the high speed rotation of the motor into a miniaturized strain wave gear system (known for powering the wheels on the Apollo Lunar Rover [2]) will allow us to provide immense mechanical advantage (up to 320:1) to reliably release our mechanism with minimum power. The application of this metallic gearing system in space was made possible thanks to the recent NASA development of Bulk Metallic Glass Gears (BMGG). This new material technology invented in NASA’s Jet Propulsion Laboratory allows metallic gears to survive temperatures down to –173 °C and to possess twice the strength of steel [3] . NASA intends for this technology to be used in gearboxes of the future to power extraterrestrial rovers. Our plan is to take this material and utilize it in our mechanism for meshing gears together without any chance of fracture or significant wear.
Utilizing this sophisticated gearing method, the motor is able to output an increased 32000% factor of power, enabling the mechanism to operate under intense load. The rotation of the gears drives a notched ring that when rotated 15 degrees, releases a spring loaded set of threaded components to allow the release of a bolt. This solution is completely one of a kind. Current assemblies reach nowhere near the minuscule volume achieved by the Wave-Lock. Let alone the relative simplicity and low power required to activate the release of the bolt.
The rapid technological evolution of satellite construction has resulted in almost origami-like unfolding behaviour in satellite deployment. As larger satellites need to be squeezed into small aerodynamic fairings, space saving mechanisms have become a must. An example of this is the James Webb Telescope which has an unfolding time of approximately 30 days. The complexity of such an arrangement would greatly benefit from a gentle bolt separation solution such as ours. Without shock-waves propagating throughout the assembly or possible debris scratching sensitive lenses, our solution is able to solve separation events by not only avoiding these side effects but at a great weight reduction (25g total weight). We are very optimistic about the potential of future applications.
Space Agency Data
Our project made use of various sources of space agency data. During our search for resources, our most notable discovery was the NASA article “Metallic Glass Gears Make for Graceful Robots [7] that concerned the use of Metallic Glass Gears in robotics. We were fascinated by the material’s unique characteristics and realized that it could be applied to our project. Ultimately, it served as the major inspiration of our final design as without it, we would have never considered gearbox applications in space.
In addition to this resource, we also drew inspiration from the strain wave gear already commonly used in spacecraft applications [2]. We knew that considering the power limitations, our input power would need to be transformed and multiplied to high factor so we could apply a greater force on the output of our assembly. The accessibility of NASA research provided us with extremely valuable inspiration to use this specific gearing mechanism.
Hackathon Journey
Our experience with this project could be described as an exhilarating crunch. We had to familiarize ourselves with a multitude of existing separation device models very quickly, ones applied both within and outside the area of spacecraft deployment. At first, we considered designing an improved version of the Deployable Stat Solar Array Mechanism [5] , however we decided on a different approach after becoming dissatisfied with the design’s need for a large compartment to catch and reserve the bolt post detachment. After this, we did some more research and fell upon a NASA article about Strain Wave gears, and our fascination with the mechanism + material application of Metallic Glasses [3] which inspired the design we ultimately settled on. We also struggled to deal with the fact that due to the challenges’ requirements, any design we created that used a motor could not consume more than 20 Watts. The use of Strain Wave gears offered an elegant solution to this problem and enabled us to come up with a design that is able to release a bolt under intense load.
References
[1] DC Brushless Motor for the Conditions of Space - https://www.maxongroup.com/maxon/view/news/maxon-drives-are-heading-to-the-Red-Planet-with-NASAs-Perseverance-rover
[2] Strain Wave Gear Spacecraft Usage - https://ntrs.nasa.gov/api/citations/20190001052/downloads/20190001052.pdf
[3] Bulk Metalic Glass Gears - https://www.nasa.gov/feature/jpl/metallic-glass-gears-make-for-graceful-robots
[4] Bulk Metallic Glass Gears (BMGG) - https://www.nasa.gov/directorates/spacetech/game_changing_development/projects/BMGG
[5] Solar Array Mechanism - https://ntrs.nasa.gov/api/citations/20150004077/downloads/20150004077.pdf
[6] James Webb Telescope - https://www.jwst.nasa.gov/content/about/launch.html
[7] Graceful Robots - https://www.nasa.gov/feature/jpl/metallic-glass-gears-make-for-graceful-robots/
Tags
#launch #satellites #exploration #invention #HDRM #revolutionary
Global Judging
This project has been submitted for consideration during the Judging process.