Metal-glass gears integrated into joints, 3D printed to make NASA’s lunar mission robots better

2022-05-12 0 By

In early 2022, the Cold Operational Lunar Deployable Arm (COLDArm) project, led by NASA’s Jet Propulsion Laboratory in Southern California, successfully integrated special gears into components of a robotic arm that is scheduled to be deployed to lunar missions in the coming years, according to 3D Science Valley’s Market Watch.These bulk metal Glass (BMG) gears, integrated into COLDArm’s joints and actuators, were developed through a game-changing program to develop bulk metal Glass (amorphous alloy) gears that operate at extreme temperatures below 280 degrees Fahrenheit (-173 degrees Celsius).In this issue, 3D Science Valley joins you to find out how technology is advancing our ability to explore the universe.© University of Southern California begins commercialization of 3D-printed metallic glass Amorphous metal (metallic glass), also known as amorphous alloy, has the advantages of both metal and glass while overcoming the disadvantages of each.For example, glass is fragile and has no ductility.High strength higher than that of steel, hardness of the metallic glass more than hard tool steel, and has a certain toughness and rigidity, so, people praised the metal glass as “knock not broken, not bad” valley of the king of the “glass” © 3 d science amorphous metal, the white paper combines so many excellent properties, such as high strength, high hardness, wear resistance and corrosion resistance, etc.These excellent performance make it in aerospace, automotive ships, armor protection, precision instruments, power, energy, electronics, biomedical and other fields have a wide range of application prospects.According to ACAM Aachen Additive Manufacturing Center, the development trend of 3D print-additive manufacturing is towards the deepening level of multi-dimension, facing the application of mass production, 3D printing breaks through the current application of economic requirements, and extends to the application end of a development path to industrialization is to achieve more complex structure of products.The metal-glass gear alloys in the robotic joints and actuators in NASA’s COLDArm project have a disordered atomic structure that makes them both strong and flexible enough to withstand these unusually low temperatures.A typical gearbox needs to be heated to operate at such low temperatures.The BMG gear motor has been tested and successfully operated at approximately -279 ° F (-173 ° C) without heating assistance.This geared motor is one of the key technologies that enables the arm to operate in extremely cold environments, such as lunar nights.One of four assembled robotic joints, including a large metal glass gear motor for each joint of the COLDArm robotic arm © Motiv Space Systems, Inc.Each of the four joints containing the BMG gear will be tested once the arm is fully assembled. Robotic joint testing will include dynamometer tests to measure torque/speed and cryothermal vacuum tests to see how the device can be used in a space-like environment.Once tested, the BMG gear and COLDArm Cold Operable Lunar Deployable Arm will perform future missions in the extreme environments of the Moon, Mars and ocean worlds.© Motiv Space Systems, Inc. The COLDArm project is funded by the Lunar Surface Innovation Program and managed by NASA’s Space Technology Mission Directorate’s Game-changing Development Program.Under NASA’s Small Business Innovation Research Program, a company called Motiv Space Systems is leading the design and manufacture of COLDArm arms and motor controllers, which 3D Science Valley believes could usher in a new era of collaborative robotics applications.In the mid-1990s, two Northwestern university professors patented an alternative concept with a new term: collaborative robotics.Collaborative robots designed to work with humans will be smaller, smarter, more responsive, more conscious, with greater self-control and better manners.In the years since, leaps in artificial intelligence and sensors have made these “friendlier” robots a reality, but cost still stands in the way of their widespread adoption.However, the biggest cost factor is not always advanced software and sensors.It also boils down to some of the most basic machine parts: gears, for example, are known to cost at least half as much as robotic arms in the manufacture of some collaborative robots.Amorphology, now based in California, hopes to bring down the price of collaboration robots, which were originally built for robots never used in human interaction (NASA’s planetary rovers).Like most gears on Earth, the gears on NASA’s rovers are made of steel, making them tough and wearable.But steel gears need fluids to lubricate them, and oil doesn’t work well in cold environments like the surface of the moon or Mars.So, for example, NASA’s Curiosity rover spends about three hours heating up lube oil each time it’s ready to start rolling, consuming about a quarter of its discretionary energy.Metallic glass (amorphous alloys) can be cooled rapidly from liquid to solid before its atoms form the lattice structure common to all other metals.Atoms are arranged randomly like glass, giving glass and metals their material properties.Depending on their composition — which typically includes zirconium, titanium and copper — metallic glasses can be very strong, and because they are not crystalline, they are elastic.Most compositions also form hard, smooth ceramic oxide surfaces, which together provide long life without lubrication for gears made of some amorphous metals.This was important to NASA because you could run the gearbox without lubricating it.Currently, the Cold Operable Lunar Deployable Arm (COLDArm), co-developed by Motiv Space Systems for lunar missions, is expected to operate at temperatures as low as -290 degrees Fahrenheit using large metal-glass gears, without the need to install a heat source.Metal glass (amorphous metal) and there is another feature, the design has a low melting point alloy, because to make a metal glass, must make the alloy cooling faster than crystallization rate, the low melting point, and their inherent strength as well as their volume during curing almost did not change the fact that it can greatly reduce the cost of manufacturing gear and other parts.However, the manufacture of metallic glass (amorphous metal) is a challenging process, especially for amorphous metallic glass which usually needs to be cooled at a higher temperature than its melting temperature and to avoid crystallization.The manufacturing process requires extraordinary cooling rates and limits the thickness they can form, since thicker parts are harder to cool quickly.The most difficult and expensive gear part machined from steel blocks is one of the most common parts in robotic arms: flexible splines, which are extremely thin-walled flexible cups with toothed edges.This is the core of the so-called wave gear assembly, where flexible splines provide better accuracy, higher torque and lower backlash than other gear sets.This eliminates positioning errors that might occur in a robotic limb with multiple joints.Flexible splines are very odd-looking gears, but they are the heart and soul of sophisticated robots.That’s where, according to 3D Science Valley, the biggest cost savings can come from molding with amorphous metal: it costs about half as much to make strain-wave gears out of steel.Amorphology, which was founded in 2014, is the core business plan of Amorphology.Through Caltech, the company has received several patents for technologies developed for NASA.Amorphology is not the first Caltech metallic glass innovation to be commercialized, but creating a start-up based on new materials is notoriously difficult, according to 3D Science Valley’s market insights.Among the difficulties is the need to find a long-term market for the material, and the Bulk metal Glass (BMG) gear is a big step towards the continued commercial success of bulk metal glass.According to market research by 3D Science Valley, California Institute of Technology (Caltech) was granted a patent for amorphous metals through additive manufacturing technology in 2017. At that time, the technology has started business cooperation dialogue with several well-known international large enterprises.Amorphology was founded by The inventor of the patent, Douglas Hofmann.Caltech makes amorphous metals by melting the surface of a first layer of metal alloy at high temperatures.This layer of molten metal alloy is rapidly cooled and solidifies to form the first layer of amorphous metal;Then on this basis for the next layer of processing.In this process, “spray technology” is applied to each layer, including plasma spraying, arc spraying and other methods.”Spray technology” can use raw materials include: wire and metal powder.According to the market research of 3D Science Valley, the “spray technology” is DED direct energy deposition 3D printing technology.The commercialization of amorphous metals has been a hot topic in the metal additive manufacturing community in 2017, according to market research from 3D Science Valley.Prior to this, EOS also invested in Amorphous metal 3D printing startup Exmet, which has been developing amorphous metal 3D printing technology in cooperation with German materials giant Heraeus Group since 2016, according to 3D Science Valley’s Market Insights. Unlike DED technology used by California Institute of Technology,Exmet is equipped with an EOS M 290 metal 3D printer in the factory to manufacture high performance amorphous metal parts.Exmet is also working with Heraeus to develop amorphous metal 3D printing technology, according to 3D Science Valley’s Market Watch. Heraeus released their amorphous metal gear manufactured using SLM (Selective Laser Melting) 3D printing technology in early April 2019.Heraeus says it is by far the world’s largest amorphous metal component. They are breaking through the boundaries of amorphous metal manufacturing and opening up new design possibilities of amorphous metal for the manufacturing industry.The 3D-printed amorphous metal gear developed by Heraeus uses topological optimization to reduce gear weight by 50% compared to traditional manufacturing processes.Through SLM 3D printing, Heraeus has redefined the limitations of traditional technologies in terms of the size and design complexity of amorphous metal gears, changing the design possibilities of such materials.According to the Institute of Physics, Chinese Academy of Sciences, China has achieved internationally remarkable research results in the basic science of metal and glass in the past decade.For example, the discovery and characterization of Beta relaxation in metallic glass, rheological mechanism of metallic glass, phase transformation in metallic glass, fracture criterion of metallic glass, physical interpretation of fracture morphology of metallic glass, elastic model of metallic glass, etc.Over the past half century, metal glass has become a popular material for high-tech products such as aerospace and mobile phones and portable computers.As glass, metal, solid and liquid properties of new metal materials, metallic glass has kept a lot of the record of metal materials, such as: so far, the metallic glass is the strongest and the most soft metal materials, is the strongest armour material, metal material processing and shaping is the easiest, is the corrosion of metal material, is one of the most ideal micro and nano materials.Metallic glass has the characteristics of heredity, memory, soft magnetism, large magnetic entropy and so on. It is also a model system for studying some important problems in materials science and condensed matter physics.L Reference patent name:systems and methods for fabricating objects including amorphous metal using techniques akin to additive 3D Science Valley provides the industry with in-depth observation of additive and intelligent manufacturing from a global perspective. For more information about the deep dive of 3D printing market, please pay attention to the Valley Frontier series released by 3D Science Valley.Please send your contributions to