NASA to Air Departure of Upgraded SpaceX Cargo Dragon from Space Station
Editor's Note: This advisory was updated on Jan. 11 to reflect the new targeted departure date and the correct weight of returning science and cargo.
The SpaceX Dragon that arrived to the International Space Station on the company’s 21st resupply services mission for NASA is scheduled to depart on Tuesday, Jan. 12, loaded with 4,400 pounds of scientific experiments and other cargo. NASA Television and the agency’s website will broadcast its departure live beginning at 8 a.m. EST.
The SpaceX Crew Dragon spacecraft is pictured approaching the International Space Station for a docking on Nov. 17, 2020.
Credits: NASA
The upgraded Dragon spacecraft will execute the first undocking of a U.S. commercial cargo craft from the International Docking Adapter about 8:40 a.m., with NASA astronaut Victor Glover monitoring aboard the station.
Dragon will fire its thrusters to move a safe distance from the station’s space-facing port of the Harmony module, then initiate a deorbit burn to begin its re-entry sequence into Earth’s atmosphere. Dragon is expected to make its parachute-assisted splashdown around 8:14 p.m. Wednesday, Jan. 13 – the first return of a cargo resupply spacecraft in the Atlantic Ocean. The deorbit burn and splashdown will not air on NASA TV.
Splashing down off the coast of Florida enables quick transportation of the science aboard the capsule to the agency’s Kennedy Space Center’s Space Station Processing Facility, and back into the hands of the researchers. This shorter transportation timeframe allows researchers to collect data with minimal loss of microgravity effects. For splashdowns in the Pacific Ocean, quick-return science cargo is processed at SpaceX’s facility in McGregor, Texas, and delivered to NASA’s Johnson Space Center in Houston.
Dragon launched Dec. 6 on a SpaceX Falcon 9 rocket from Launch Complex 39A at NASA’s Kennedy Space Center in Florida, arriving at the station just over 24 hours later and achieving the first autonomous docking of a U.S. commercial cargo resupply spacecraft. Previous arriving cargo Dragon spacecraft were captured and attached to the space station by astronauts operating the station’s robotic Canadarm2. The spacecraft delivered more than 6,400 pounds of hardware, research investigations and crew supplies.
The upgraded cargo Dragon capsule used for this mission contains double the powered locker availability of previous capsules, allowing for a significant increase in the research that can be carried back to Earth.
Some of the scientific investigations Dragon will return to Earth include:
Cardinal Heart
Microgravity causes changes in the workload and shape of the human heart, and it is still unknown whether these changes could become permanent if a person lived more than a year in space. Cardinal Heart studies how changes in gravity affect cardiovascular cells at the cellular and tissue level using 3D-engineered heart tissues, a type of tissue chip. Results could provide new understanding of heart problems on Earth, help identify new treatments, and support development of screening measures to predict cardiovascular risk prior to spaceflight.
Space Organogenesis
This investigation from JAXA (Japan Aerospace Exploration Agency) demonstrates the growth of 3D organ buds from human stem cells to analyze changes in gene expression. Cell cultures on Earth need supportive materials or forces to achieve 3D growth, but in microgravity, cell cultures can expand into three dimensions without those devices. Results from this investigation could demonstrate advantages of using microgravity for cutting-edge developments in regenerative medicine and may contribute to the establishment of technologies needed to create artificial organs.
Sextant Navigation
The sextant used in the Sextant Navigation experiment will be returning to Earth. Sextants have a small telescope-like optical sight to take precise angle measurements between pairs of stars from land or sea, enabling navigation without computer assistance. Sailors have navigated via sextants for centuries, and NASA’s Gemini missions conducted the first sextant sightings from a spacecraft. This investigation tested specific techniques for using a sextant for emergency navigation on spacecraft such as NASA’s Orion, which will carry humans on deep-space missions.
Rodent Research-23
This experiment studies the function of arteries, veins, and lymphatic structures in the eye and changes in the retina of mice before and after spaceflight. The aim is to clarify whether these changes impair visual function. At least 40 percent of astronauts experience vision impairment known as Spaceflight-Associated Neuro-ocular Syndrome (SANS) on long-duration spaceflights, which could adversely affect mission success.
Thermal Amine Scrubber
This technology demonstration tested a method to remove carbon dioxide (CO2) from air aboard the International Space Station, using actively heated and cooled amine beds. Controlling CO2 levels on the station reduces the likelihood of crew members experiencing symptoms of CO2 buildup, which include fatigue, headache, breathing difficulties, strained eyes, and itchy skin.
Bacterial Adhesion and Corrosion
Bacteria and other microorganisms have been shown to grow as biofilm communities in microgravity. This experiment identifies the bacterial genes used during biofilm growth, examines whether these biofilms can corrode stainless steel, and evaluates the effectiveness of a silver-based disinfectant. This investigation could provide insight into better ways to control and remove resistant biofilms, contributing to the success of future long-duration spaceflights.
Learn more about SpaceX missions for NASA at:
https://www.nasa.gov/spacex
Stephanie Schierholz / Monica Witt
Headquarters, Washington
202-358-1100
stephanie.schierholz@nasa.gov / monica.j.witt@nasa.gov
Leah Cheshier
Johnson Space Center, Houston
281-483-5111
leah.d.cheshier@nasa.gov
Editor: Sean Potter
https://www.nasa.gov/press-release/nasa-to-air-departure-of-upgraded-spacex-cargo-dragon-from-space-station
Redwire Technology Successfully Manufactures Ceramic Part in Space for the First Time
World’s first-ever demonstration of ceramic additive manufacturing in space
Jacksonville, FL (December 2, 2020) – Redwire, a new leader in mission critical space solutions and high reliability components for the next generation space economy, announced today that the company’s Ceramic Manufacturing Module (CMM) successfully manufactured a ceramic part in space for the first time.
The commercially developed in-space manufacturing facility successfully operated with full autonomy using additive stereolithography (SLA) technology and pre-ceramic resins to manufacture a single-piece ceramic turbine blisk on orbit along with a series of material test coupons. The successful manufacture of these test samples in space is an important milestone to demonstrate the proof-of-potential for CMM to produce ceramic parts that exceed the quality of turbine components made on Earth. The ceramic blisk and test coupons will be stowed and returned to Earth for analysis, aboard the SpaceX Dragon CRS-21 spacecraft. CMM, developed by Redwire subsidiary Made In Space, is the first SLA printer to operate on orbit.
“This is an exciting milestone for space enabled manufacturing and signals the potential for new markets that could spur commercial activity in low Earth orbit,” said Tom Campbell, president of Made In Space. “Building on our in-space manufacturing expertise and our partnership with NASA, Redwire is developing advanced manufacturing processes on orbit that could yield sustainable demand from terrestrial markets and creating capabilities that will allow humanity to sustainably live and work in space.”
CMM aims to demonstrate that ceramic manufacturing in microgravity could enable temperature-resistant, reinforced ceramic parts with better performance, including higher strength and lower residual stress. For high-performance applications such as turbines, nuclear plants, or internal combustion engines, even small strength improvements can yield years-to-decades of superior service life.
“The Ceramic Manufacturing Module’s successful on-orbit operations is an important step towards full-scale manufacturing of materials products that can improve industrial machines that we use on Earth,” said Michael Snyder, chief technology officer of Redwire. “The space manufacturing capabilities demonstrated by CMM have the potential to stimulate demand in low Earth orbit from terrestrial markets which will be a key driver for space industrialization.”
CMM was developed in partnership with the ISS Research Integration Office at NASA’s Johnson Space Center. The ceramic facility is one of three ISS pilot payloads developed through this partnership that aims to catalyze and scale demand for commercial capabilities in low Earth orbit by producing high-value products for terrestrial use. Made In Space first demonstrated the SLA printing technology found inside CMM through a series of parabolic flights funded through NASA’s Flight Opportunities program in 2016.
Additional technical partners for the CMM mission include HRL Laboratories of Malibu, California and Sierra Turbines of San Jose, California.
The successful CMM mission builds upon Redwire’s flight heritage with four other additive manufacturing facilities developed by the Made In Space team that have successfully flown and operated on the space station.
To learn more about CMM, visit https://madeinspace.us/capabilities-and-technology/ceramics-manufacturing/.
Ceramics Manufacturing: Increasing Capability + Scaling Commercial Industry in Space
Made In Space (MIS) is set to launch its newest manufacturing facility to the International Space Station (ISS), introducing another brand new manufacturing capability from the MIS team. This significant milestone will be the fifth facility launched by the company and the fifth unique capability brought to the ISS.
The Ceramic Manufacturing Module (CMM) will be on Northrop Grumman’s 14th commercial resupply mission aboard the Cygnus spacecraft. The technology is a commercial in-space manufacturing device designed to provide proof-of-potential for single-piece ceramic turbine blisk (blade + disk) manufacturing in microgravity for terrestrial use. This marks the first ceramic facility on the ISS.
Techniques + Comparison
The Ceramics Manufacturing Module (CMM) is a unique manufacturing technology that introduces both an innovative new manufacturing capability on-orbit and a new material medium to fabricate with. CMM will demonstrate the viability of manufacturing with pre-ceramic resins in an additive stereolithography (SLA) environment. Manufacturing on-orbit in the microgravity environment could enable temperature-resistant, reinforced ceramic parts with better performance including higher strength and lower residual stress, due to a reduction in defects caused by gravity, such as sedimentation and composition gradients that occur in terrestrial manufacturing.
The CMM facility performs a uniform stereolithography printing process that has been validated on NASA-sponsored parabolic flights for high-resolution parts. The initial design process and technical advisory during the parabolic flights were provided by commercial partner, B9Creations. The manufacturing process being flown employs the use of pre-ceramic resins. These resins are the soft materials present before the manufacturing begins that become hardened during the process.
Stereolithography or Digital Light Processing (DLP) is a mature, high-resolution 3D printing approach based on UV curing of liquid resins in a layer-by-layer fashion. Beyond a range of polymers, this method is also used for additive manufacturing of ceramics. To this end, ceramic particles are suspended in the liquid resin. MIS will print an advanced ceramic matrix composite (CMC) material that consists of a pre-ceramic resin reinforced with ceramic particles. The microgravity environment on the ISS is considered especially beneficial for processing such particle suspensions as the settling of particles is mitigated.
This new additive manufacturing process varies in technique from our heritage 3D printing facilities. The MIS Additive Manufacturing Facility (AMF) that has been operating on the ISS since 2016, uses a manufacturing process called Fused Deposition Modeling (FDM). This process builds an object by selectively depositing melted filament material in a predetermined path, layer-by-layer. AMF’s legacy has been the foundation for the technology roadmap and manufacturing programs for MIS while developing new capabilities that will leverage additive manufacturing in space for unprecedented applications.
Industry Applications
The project focuses on advanced materials engineering ultimately leading to reductions in part mass, residual stress, and fatigue. The facility is designed to accommodate additive ceramic sample materials identified by MIS and customers as having the highest value for production. This will help to validate the uniformity, low density, and high performance of printed ceramic blisks as compared with ground analogs. For high-performance applications such as turbines, nuclear plants, or internal combustion engines, strength improvements of even 1-2 percent can yield years-to-decades of superior service life.
Once the manufacturing device returns to Earth, the manufactured blisks are then heat-treated or pyrolyzed to create the final product of a Ceramic Matrix Composite (CMC). CMCs have the potential to perform at hundreds of degrees hotter than the best superalloys and can have a clear advantage over previously used metal components used in aircraft engines.
MIS is developing this technology for commercialization alongside technical partners HRL Laboratories of Malibu, California and Sierra Turbines of San Jose, California.
“Our main interest in utilizing space-enabled materials lies in harnessing the performance benefits they enable for our and our partners’ products, and thus giving us a competitive advantage in meeting demand in these two markets:
1) space vehicle applications, such as satellites in various orbits and spacecraft heading to the lunar and Martian surfaces, that must handle highly reactive atomic oxygen or withstand high-energy particles
2) Earth-based high-performance applications, such in Sierra Turbines’ ultra-high temperature turbine blades, where the absence of buoyancy-driven convection and sedimentation allows vastly improved micro-structures not possible to create terrestrially”
Roger Smith, CEO, Sierra Turbines
Single-piece turbine blisks have significant advantages over current assemblies used in aircraft jet engines and integrated rotors. CMCs are typically lighter than high-temperature alloys by 30-50 percent and are capable of handling much higher operating temperatures, measuring above 1100 °C, which can improve fuel economy and efficiency in larger aircraft engines. Successful production in microgravity may provide additional gains in decreasing the mass and residual stress of these parts and increasing their fatigue strength which could convey significant advantages to the aviation industry.
Internal projection of the blisk to be printed in the pre-ceramic resin
Ceramic blisks before and after being pyrolyzed
Leveraging Space-Enabled Manufacturing for a Sustainable Low-Earth Orbit Economy
Ceramics produced in microgravity will open opportunities for complex-shaped, temperature resistant, and environment resistant ceramic structures addressing defects common to terrestrial printed parts including porosity and non-uniform shrinkage. The parts that are produced on-orbit will be compared with parts produced terrestrially with MIS hardware as well as commercially available materials.
Ceramics Manufacturing Module Team
CMM is part of MIS’s expanding Space-enabled manufacturing portfolio. Space-enabled manufacturing is a form of in-space manufacturing that leverages microgravity to manufacture materials that are either completely new or far superior to their Earth-manufactured counterparts. MIS has a comprehensive suite of ISS rack-based payloads for a variety of advanced manufacturing techniques and facilities with broad applications not limited to proof-of-potential “blisks”. The primary objective for each of these facilities on their first flight will be to demonstrate the technology operates as intended and to produce the material product so that we can analyze those samples on the ground.
These space-enabled materials are realized through the unique microgravity environment that has the ability to alter materials at their atomic level to create a superior product in-space compared to the terrestrial analog of that material. By identifying advanced manufacturing processes that address specific markets and add greater value to the products needed in those markets, along with a scalable approach for meeting the market’s need, space-enabled manufacturing creates a space-Earth value chain to spur commercial activity.
This type of manufacturing represents a key differentiator in how space is utilized for commercial expansion. By leveraging the microgravity environment we are able to economically manufacture new and innovative products that can be sold on Earth. Space-enabled manufacturing is critical to the MIS mission because it creates a profit motive that can scale demand for on-orbit manufacturing capabilities and services which translates to the growth of new markets in the LEO economy and increases demand from terrestrial customers.
Northrop Grumman is targeting liftoff of its Antares launch vehicle for no earlier than 10:26 p.m. EDT Tuesday, Sept. 29, from the Mid-Atlantic Regional Spaceport’s Pad-0A at NASA’s Wallops Flight Facility on Wallops Island, Virginia.
NASA - Space Station Research: Turbine Ceramic Manufacturing Module
(Turbine CMM) demonstrates manufacture of single-piece turbine blade/disk combinations (blisks) in microgravity for commercial use. Manufacturing blisks in space could produce parts with lower mass and residual stress and higher strength than those made on Earth due to greatly reduced sedimentation of the solution in microgravity.
SCIENCE RESULTS FOR EVERYONE
The following content was provided by Michael Snyder, and is maintained in a database by the ISS Program Science Office.
Experiment Description
RESEARCH OVERVIEW
The Turbine Ceramic Manufacturing Module (Turbine CMM) investigates the capability to produce ceramic single-piece turbine blisks in microgravity for commercial use on Earth.
Turbine CMM tests whether flight samples have lower part mass and residual stress and higher strength than units manufactured on the ground.
DESCRIPTION
The Turbine Ceramic Manufacturing Module (Turbine CMM) is a commercial in-space manufacturing device designed to provide proof-of-principle for single-piece ceramic turbine blisk (blade/disk) manufacturing in microgravity for terrestrial use. The Turbine CMM project focuses on advanced materials engineering leading to reductions in part mass, residual stress and fatigue. This project is similar to the Turbine Superalloy Casting Module (Turbine SCM) device also designed by Made In Space.
Applications
SPACE APPLICATIONS
This investigation demonstrates potential use of the space station for unique manufacturing capabilities, contributing to the increased commercialization of space.
EARTH APPLICATIONS
Single-piece turbine blisks have significant advantages over current assemblies used in aircraft jet engines and integrated rotors. Successful production in microgravity may provide additional gains in decreasing the mass and residual stress of these parts and increasing their fatigue strength. This could convey significant advantages to the aviation industry.
Operations
OPERATIONAL REQUIREMENTS AND PROTOCOLS
The Turbine CMM is installed in an EXPRESS single locker location. The Turbine CMM has similar space station interfaces and controls as the Additive Manufacturing Facility (AMF) and operates autonomously except for initial activation and parts changeout.
Made In Space Makes History With Manufacturing @ ISS + Also Receives Prestigious NASA Award
Redwire recently announced that the company’s Ceramic Manufacturing Module (CMM) successfully manufactured a ceramic part in space for the first time.
The commercially developed in-space manufacturing facility successfully operated with full autonomy using additive stereolithography (SLA) technology and pre-ceramic resins to manufacture a single-piece ceramic turbine blisk on-orbit, along with a series of material test coupons. The successful manufacture of these test samples in space is an important milestone to demonstrate the proof-of-potential for CMM to produce ceramic parts that exceed the quality of turbine components made on Earth.
The ceramic blisk and test coupons will be stowed and returned to Earth for analysis, aboard the SpaceX Dragon CRS-21 spacecraft. CMM, developed by Redwire subsidiary Made In Space, is the first SLA printer to operate on-orbit.
CMM aims to demonstrate that ceramic manufacturing in microgravity could enable temperature-resistant, reinforced ceramic parts with better performance, including higher strength and lower residual stress. For high-performance applications such as turbines, nuclear plants, or internal combustion engines, even small strength improvements can yield years-to-decades of superior service life.
CMM was developed in partnership with the ISS Research Integration Office at NASA’s Johnson Space Center. The ceramic facility is one of three ISS pilot payloads developed through this partnership that aims to catalyze and scale demand for commercial capabilities in LEO by producing high-value products for terrestrial use. Made In Space first demonstrated the SLA printing technology found inside CMM through a series of parabolic flights funded through NASA’s Flight Opportunities program, in 2016.
Additional technical partners for the CMM mission include HRL Laboratories of Malibu, California, and Sierra Turbines of San Jose, California.
The successful CMM mission builds upon Redwire’s flight heritage with four other additive manufacturing facilities developed by the Made In Space team that have successfully flown and operated on the space station.
“This is an exciting milestone for space enabled manufacturing and signals the potential for new markets that could spur commercial activity in low Earth orbit,” said Tom Campbell, the President of Made In Space. “Building on our in-space manufacturing expertise and our partnership with NASA, Redwire is developing advanced manufacturing processes on orbit that could yield sustainable demand from terrestrial markets and creating capabilities that will allow humanity to sustainably live and work in space.”
“The Ceramic Manufacturing Module’s successful on-orbit operations is an important step towards full-scale manufacturing of materials products that can improve industrial machines that we use on Earth,” said Michael Snyder, CTO of Redwire. “The space manufacturing capabilities demonstrated by CMM have the potential to stimulate demand in low Earth orbit from terrestrial markets which will be a key driver for space industrialization.”
Additionally, Redwire subsidiary Made In Space (MIS) was awarded the Exceptional Technology Achievement Medal at the 2020 NASA Honor Awards Ceremony hosted virtually by NASA’s Johnson Space Center. The medal was awarded for the Made In Space team’s exceptional and pioneering success developing and operating in-space manufacturing facilities on the International Space Station (ISS) while furthering the commercialization of LEO.
Andrew Rush
This prestigious NASA medal is awarded to Government or non-Government individuals for exceptional technology contributions significantly contributing toward the achievement of the NASA mission. The medal was presented to Redwire COO Andrew Rush in recognition of the team’s exceptional efforts.
To date, Redwire’s flight heritage on the ISS includes five facilities, developed by MIS teams, that have pioneered in-space manufacturing and paved the way for manufacturing with specialized materials in orbit to benefit Earth.
MIS teams are currently developing three ISS pilot payloads, through a partnership with the ISS Research Integration Office at NASA’s Johnson Space Center, that aim to catalyze and scale demand for commercial capabilities in LEO by producing high-value products for terrestrial use. The facilities include the Ceramic Manufacturing Module (CMM), Industrial Crystallization Facility (ICF), and the Turbine Superalloy Casting Module (TSCM).
CMM, which launched in October 2020 on Northrop Grumman’s CRS-14 mission successfully demonstrated ceramic additive manufacturing in space for the first time in history, earlier this week. The facility is designed to provide proof-of-potential for single-piece ceramic turbine blisk (blade + disk) manufacturing in microgravity for terrestrial use.
The Made in Space ICF team.
The next manufacturing facility set to launch to the ISS is ICF—a commercial, in-space manufacturing device designed to provide proof-of-principle for diffusion-based crystallization methods to produce high quality crystals in microgravity relevant for terrestrial use.
The Made in Space TSCM team.
ICF will be followed by TSCM, which will investigate potential improvements in superalloy microstructure by heat treating in microgravity.
These advancements in space enabled manufacturing capabilities could signal new opportunities for LEO commercialization.
Made In Space is sending the first ceramic manufacturing facility in space to the ISS next week
Image Credits: European Space Agency (opens in a new window) / Flickr (opens in a new window) under a CC BY-SA 2.0 (opens in a new window) license.
In-space manufacturing company Made In Space is pushing the envelope on what can, well, be made in space with its next mission — which is set to launch aboard a Northrop Grumman International Space Station (ISS) resupply mission set for next Tuesday. Aboard that launch will be Made In Space’s Turbine Ceramic Manufacturing Module (aka CMM), a commercial ceramic turbine blisk manufacturing device that uses 3D printing technology to produce detailed parts that require a high degree of production accuracy.
A turbine blisk is a combo rotor disk/blade array that is used primarily in engines used in the aerospace industry. Making them involves using additive manufacturing to craft them as a single component, and the purpose of this mission is to provide a proof-of-concept about the viability of doing that in a microgravity environment. Gravity can actually introduce defects into ceramic blisks manufactured on Earth, because of the way that material can settle, leading to sedimentation, for instance. Producing them in microgravity could mean lower error rates overall, and a higher possible degree of precision for making finely detailed designs.
Made In Space to launch it’s latest AM technology to the ISS
Space bound 3D printer to test viability of producing high performance ceramic parts using micro-gravity environment.
(Photo credit: Made In Space)
Made In Space (MIS) announced it will launch its additive manufacturing Ceramic Manufacturing Module (CMM) to the International Space Station (ISS) on Sept. 29, as part of Northrop Grumman’s 14th commercial resupply mission aboard the Cygnus spacecraft.
CMM will demonstrate the viability of manufacturing with pre-ceramic resins – soft materials present before the manufacturing begins that become hardened during the process – in a stereolithography (SLA) environment. According to the company, manufacturing on-orbit in the microgravity environment could enable temperature-resistant, reinforced ceramic parts with better performance. Those improvements include higher strength and lower residual stress, due to a reduction in defects caused by gravity, such as sedimentation and composition gradients that occur in terrestrial manufacturing.
Stereolithography or Digital Light Processing (DLP) is a high-resolution 3D printing approach based on UV curing of liquid resins in a layer-by-layer fashion. For CMM, MIS will print an advanced ceramic matrix composite (CMC) material that consists of a pre-ceramic resin reinforced with ceramic particles. The microgravity environment on the ISS is considered especially beneficial for processing such particle suspensions as the settling of particles is mitigated.
Once the manufacturing device returns to Earth, the manufactured blisks are then heat-treated to create the final product of a Ceramic Matrix Composite (CMC). CMCs have the potential to perform at hundreds of degrees hotter than the best superalloys and can have a clear advantage over previously used metal components used in aircraft engines.
MIS is developing this technology for commercialization alongside technical partners HRL Laboratories of Malibu, California and Sierra Turbines of San Jose, California.
https://madeinspace.us
Flying high with 40X reliability: Sierra Turbines aims to move the small-engine industry forward
By Kip Hanson
Making gas microturbines more robust, 50% lighter, and with 10 times the energy efficiency using metal 3D printing from VELO3D
Will Hasting (left) of VELO3D and Roger Smith (right), CEO of Sierra Turbines.
Roger Smith is breaking the rules of manufacturing. The chief executive officer of San Jose, California-based Sierra Turbines Inc., he’s discarded the industry’s long-held belief that additive manufacturing (AM) is limited to prototyping and low-volume work. In fact, Smith plans to additively manufacture 95% or more of his microturbine components even when he reaches large-scale production.
Apple to aircraft
Smith doesn’t care that he’s discarding several other industry beliefs, among them the notion that overhauling microturbines every 40 to 50 hours is acceptable.
The VELO3D Sapphire metal printer
Smith is unhappy with much of the small-engine status quo. A microturbine has historically been a simplified version of its full-size counterpart; cost restrictions have always prohibited manufacturing complex features that would give microturbines improved performance. With a little radical thinking and a hefty dose of advanced technology, he’s prepared to change it.
One of the key pillars of this advanced technology in Smith’s arsenal is the metal AM system from manufacturer VELO3D, located just a few minutes south of Sierra Turbines in Campbell. Says Smith, “We opened the company in 2017, and within the first year or so had pretty much scoured the planet for a 3D-printing process to produce our parts. That’s when we learned about VELO3D. We were all quite surprised—and pleased—to discover they are just down the street from us. It makes our work together that much easier.”
The “we” in this story is Smith’s team of scientific and technical professionals. Some have gas turbine expertise; others are extremely knowledgeable in software and control systems (Smith himself spent 19 years with Apple before launching Sierra Turbines). All have worked in Fortune 100 product environments. Together they boast a combined 70 years of industry experience, with each team member sharing the same goal—to design and manufacture better solutions for the burgeoning microturbine market.
Microturbines are suitable for a variety of applications, Smith explains. They can be used to meet land-based power generation needs, where microturbine-based systems not much larger than a washing machine serve as auxiliary power units (APUs) in backup generators and other standby electrical-generation needs.
They are also of importance for unmanned aerial vehicles, or UAVs. Where gas turbine engines weighing many thousands of pounds push commercial and military aircraft through the skies every day, microturbines perform a less dynamic, though just as important, task: powering the electric motors that keep UAVs aloft. They can also be used to charge the batteries that drive those motors, as range extenders, or in hybrid UAVs that alternate between batteries and motors.
The Aurelius Mk1 Project
Sierra Turbines named their microturbine “Aurelius Mk1,” drawing on that historical period when engines were named after Greek or Roman mythology. Inspired by the Rolls Royce Olympus engines that first powered the Concorde supersonic airliner, Aurelius also happens to be the name of Smith’s late father. Sierra Turbines intends to honor that namesake by challenging the status quo.
The time between overhaul (TBO) for most small turbine engines averages 40 to 50 hours. Smith intends to raise that value to 1000+ hours, on par with commercial aircraft. He also plans to reduce engine weight to a kilogram or less, cut noise, and improve fuel efficiency, all while making the turbines easier to manufacture. These are lofty goals, yet ones shared by practically everyone making microturbines. He’s confident that his team will succeed where others have failed, however, through a host of design improvements only made possible with advanced metal AM.
Smith sees his efforts as part of a bigger picture, work that will contribute towards a revitalization of the country’s manufacturing sector. “My thoughts are these,” he says. “If we as a country are to start building products in the U.S. again, we must develop better ways of designing and fabricating products. This includes less reliance on tooling, most of which has been shifted to China, but also an embrace of Industry 4.0 and other change-making technologies. Metal 3D printing is one of these change-makers. It’s far less wasteful than traditional manufacturing and presents endless opportunities for part consolidation, lightweighting, greater product efficiency…the list goes on.”
One example of this new approach to design efficiency is the Aurelius combustor. It’s the heart of any microturbine and the test case by which Smith would determine which providers were able to deliver on the promise of additive. The component contains hundreds of small, oddly shaped holes, delicate mesh-like webbing, dozens of internal cooling channels, and a series of thin, exceedingly tall walls. And where the initial design contained 61 discrete parts, that number fell to a consolidated “unicore” engine after Sierra Turbine's designers gave it an additive makeover with computational modeling software tools.
Key differentiators
It's this highly sophisticated design that Smith presented to various additive equipment manufacturers, challenging them to build the part from Hastelloy® X, a high-strength, low-creep metal that's favored by commercial-aircraft manufacturers. The heat-resistant superalloy is also vital to Smith's reliability and fuel-efficiency goals, as it will allow his engine to reach temperatures previously unattainable in microturbines. "The hotter you go in any gas turbine, the better the performance," he says.
Smith isn’t naming names, except to say that "everyone else failed" in their attempts to build the thin-walled, high-aspect-ratio combustor. “The team at VELO3D worked with us on the design, tweaking things to make it more manufacturable, but it was their Flow software that was perhaps the biggest enabler,” Smith says, “It contains a number of special tools that provide valuable feedback throughout the entire print-preparation process.
He noticed a range of hardware differentiators as well. “It was obvious to me early-on that the VELO3D platform offers a different approach to laser powder-bed fusion (LPBF)," he adds. “For starters, their non-contact recoater blade is especially well-suited to print thin-walled sections—in some areas, our walls are less than one millimeter thick, and these tended to break off on other 3D printers.”
Smith also notes VELO3D’s ability to eliminate supports on shallow overhangs. This attribute provides for internal features that would otherwise be impossible to produce, as well as the smooth surface finishes printed by the Sapphire metal AM system. Each of these reduces the need for secondary machining and other finishing processes, something the team at Sierra Turbines wishes to avoid wherever possible.
Finally, the system’s quality assurance software, Assure, documents all the critical sensor data that affect part quality and produces a comprehensive build report for traceability. Armed with data points concerning protrusions, oxygen level, filter life, and laser alignment, Sierra Turbines has confidence that the part built was indeed a good part. “This level of quality assurance is what will move the AM industry forward,” notes Smith.
Reducing the pain of traditional manufacturing
The cost and energy savings by the consolidation of 61 parts into one part cannot be overstated. Production and transport of different raw materials, manufacture of individual parts using different processes, shipping of individual parts, tedious assembly work, joints of dissimilar materials, reliance on extra seals or fasteners, and more: All of this waste is simply eliminated by the integration of many parts into one printed part which subsequently requires minimal post-processing. “3D printing eliminates a great deal of manufacturing pain,” Smith says.
Ready for takeoff
Smith is just getting started. Once the combustor has been thoroughly tested and benchmarked, he intends to pursue additional performance improvements. He's also planning to work on the microturbine's rotating components, an unorthodox move that many aerospace pundits would agree is beyond the pale. Here again, Smith is determined. “VELO3D believes that you can use additive for full-scale production, and so do I,” he says.
Nor is his decision solely a matter of lower cost, shorter lead-times, or abbreviated supply chains. By allowing Sierra Turbines to consolidate dozens upon dozens of components into a single 3D-printed piece, one with lower mass and greater mechanical integrity than the welded and assembled alternative, support-free printing technology is enabling this small company to meet its design goals. Smith fully expects to meet or exceed his TBO goal of 1000 hours, among other objectives.
“I believe that technology should be a servant to the design, not the other way around,” Smith says. “My design team is freed from the constraints of traditional manufacturing and even existing metal AM technologies such that they can focus purely on defining the geometry needed to maximize performance and differentiation. For future gas turbine development, we aim to leverage the power of additive manufacturing to integrate features such as an efficiency-boosting recuperator, printed-in sensors, and more novel insulating and cooling geometries.”