Leveraging small sats for defense: A matter of commoditization

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June 14, 2021

Defense-industry professionals know it’s an exciting time to be an entrepreneur in space. Past obstacles like launch cost and highly customized design are becoming increasingly less daunting setbacks for makers and users alike, consequently encouraging entrance and proliferation.

Whether the need is to detect hypersonic weapons, enable robust communication, or provide detailed imagery to the armed forces, satellites serve the same purpose that most military technology is designed to achieve: to keep the warfighter safe and informed. What separates small sats from ground-based systems, however, is that the technology needs to operate in challenging space environments.

Entities like the Missile Defense Agency (MDA) and the Space Development Agency (SDA) are looking to small sats to try and redefine the platform, highlighting the benefits of a smaller, more affordable proliferated constellations over their exquisite counterparts. The higher production volume of small sat constellations and the ability to tailor the whole architecture to a specific mission are driving demand, and military suppliers are rising to meet it.

The beauty of small sats is that they aren’t a one-trick pony. The flexibility in these systems’ designs has solidified their place in both space communities and their corresponding markets and has encouraged significant investment and ingenuity amid resolute pushes to lower cost and speed deployment.

Commodities and venture capital in space

With the U.S. Department of Defense (DoD) favoring layered sensing infrastructures to provide warfighters with intelligence and surveillance during missions, so-called exquisite constellations of satellites like Space-Based Infrared Systems (SBIRS) and Overhead Persistent Infrared (OPIR) (“exquisite” satellites are large, highly sophisticated satellites usually used in geosynchronous orbit for imagery, missile-warning, and intelligence missions) can often accomplish the cost-cutting objective. While small sats alone ameliorate price concerns simply because of their size and life cycle, the commoditization of parts has its part in changing the game as well.

“As we go to more small sats, we’ve been able to use parts that have been commoditized,” says Jackie Schmoll, general manager for mission solutions at L3Harris Space and Airborne Systems (Figure 1). “For example, I know one company uses commoditized car parts in some cases versus aerospace parts. One of our constellations at L3Harris used computer parts that we added some resiliency to. From a small-sat perspective, they don’t typically have to last for 10 years. They’re usually going to be two- to three-year missions, because the whole concept is that you would be able to launch additional small sats into the constellation on a more recurring basis.”

[Figure 1 | Artist’s rendering of L3Harris small satellites in orbit.]

Commercial investment has been another proponent of getting small sats up into orbit. A small-sat market forecast posted by Space News in February 2020 highlighted how much of the growth within the small-sat market is driven predominantly by commercial companies like SpaceX and OneWeb, which has in turn somewhat liberated military-­satellite suppliers from governmental budget constraints.

“It really goes back to that commoditized cost of the components that they use to build as well as some of the ability that start-up companies, as well as venture capital-backed companies, have brought into the industry,” Schmoll says. “We sometimes talk internally that some companies have access to dollars that in some cases exceeded what the government was putting into missions. So, that investment has created new creativity and speed.”

But this isn’t to say that small sats haven’t always been a prevalent player in the satellite market – they just weren’t as widely embraced as they are today following the platforms’ increases in mission relevance. This present-day utilization spans industries, and satellite manufacturers are eager to see the widespread small sat recognition.

“Small sats are great for being able to lower the barrier of entry for any organization whether it’s a commercial company, another nation that wasn’t previously a space actor, universities, non-profits – so, all of this is not just for the commercial industry but for the ability to put assets in space that cost has gone down with the proliferation and popularity of small sats,” says JB Young, strategy and business development analyst at Lockheed Martin. “It has also made proliferation attainable, so for commercial entities wanting to provide sat services requiring things like rapid revisit times or continuous coverage, it has made that a more viable business model.”

Commoditization of satellite parts and eager investments in commercial-space actors have provided the acquisition of defense and consumer small sats with quite the running start. However, some missions require more. Bottom line: The robustness of the small sat will depend on mission need.

Investment from primes

The continued success of small sats in the commercial world has also motivated defense prime contractors. “As more and more small sats become more and more capable, all of the large primes are playing in that world,” Schmoll says. “Five or 10 years ago, we didn’t really see them investing in small sat capabilities. Since then, Boeing bought Millennium, Northrop Grumman bought Orbital, Lockheed Martin partnered with Tyvak. I think that’s going to continue, where you’ll start to see that the large primes are doing both because both are important. Things are happening that venture-capital and commercially backed industry are allowing all of us to catch up to, versus having to wait only on government funding.”

Size no longer determines robustness

“If a mission needs high availability, it needs to be highly robust and puts the satellite in more of that exquisite category,” Schmoll says. “Larger and longer-life satellites typically have more redundancy and robustness than that of the small sat because the time, effort, and dollars invested toward building and launching a larger satellite demands making sure that it’s not going to power off because of a solar flare or an anomaly. Although, if a customer needs to put something up there that is agile and needs to get up there quickly, or they’re putting it up as part of a constellation, that might not require as much robustness.”

In short, there’s no comparing system complexity between small sats and larger, longer-life satellites because which one is used depends on the requirements of the operation. It’s a matter of symbiosis in space. Manufacturers are designing small sats with mission resilience in mind as small sats can contribute to mission robustness by augmenting other platform capabilities.

“If you are trying to compare apples to apples and you’re looking at a small sat platform and a larger sat platform, and you’re talking ‘what is the lifetime reliability’ and so on, any spacecraft can be designed for the required level of mission assurance,” Young says. “However, given the limited volume within small sats, you’re going to have issues with redundant systems, or space-qualified electronics, so you might not be able to achieve the same lifetime or reliability, but you can add in or design in mission assurance to any spacecraft size.”

Considering where the bar was set for small-sat robustness in the past, the platforms are far exceeding the expectations of industry professionals today. In areas like remote sensing, both military and commercial satellites didn’t need to achieve much to be considered operationally accomplished.

“Ten years ago, there was a dramatic difference in robustness between the U.S. government and the commercial industry; the mortality rate was high for the burgeoning remote-sensing community, and success criteria required only a few months operation on-orbit,” says Barry Kirkendall, technical director for the Defense Innovation Unit’s (DIU) Space Portfolio. “Today, the reliability of small sats has significantly improved with several years of life expectancy being common, even without traditional mission-assurance practices such as multiple redundancies, space-qualified components, and the like.”

Small sats are also currently being developed for multiple orbit altitudes, which require varying radiation-hardening requirements. Depending on mission requirements, overall architecture robustness is closely tied to whether or not the customer needs more or less stringent radiation hardening.

“Radiation-hardening is largely a function of where a spacecraft is designed to operate rather than the size of the spacecraft,” Kirkendall says. “There is a nascent market for small sats to be operated in geosynchronous and cislunar [between the Earth and the moon] orbits, which would require design for higher-radiation environments than ­similar satellites in low Earth orbit. Interestingly, radiation hardening is much more than radiation-tolerant components; other aspects include resilient system architecture, selective mission redundancies for critical functions, and software voting ­techniques to identify when a single-event upset has occurred.”

This level of small sat mission robustness, however, doesn’t come without a cost. While there are customers willing to pay the full price for a highly reliable small-sat architecture, others have a stricter budget. When reliability is paramount but can also drive up the cost, satellite suppliers then must work alongside the customer to find a balance.

Balancing cost and reliability

“Efficiency isn’t always cheap,” Schmoll says. “We’ve had customers where cheap was what they wanted to go for, and the challenge became that they were paying for it in the end because they needed to work around issues that came up after designing something less costly. So, one of the biggest challenges is that there might be parts that are available in different industries at different price points that are a good starting point. In the small-sat area, there has been a lot of research on the different types of parts to see what we could take advantage of.”

Establishing an all-encompassing outlook seems to be the best path for the customer-engineer partnership when designing small sats. Asking up front what specific types of redundancy is needed, the key mission requirements, and how much availability across the system is necessary boosts the chances of reaching an ideal price point without sacrificing the operation.

“Customers often want something that is very reliable but also very low cost,” says Dr. David J. Barnhart, director for technology demonstrations with military space at Lockheed Martin (Figure 2). “So, we work with the customer to determine what are the most driving requirements of the mission, and we can tailor the capability of the small sat or sats to make sure that their key mission requirements are met.”

[Figure 2 | An artist’s rendering of two Lockheed Martin 12U satellites built for the Linus mission launching later this year in a geostationary orbit.]

After tackling the initial cost, designers must overcome reduced size, weight, and power (SWaP) challenges.

“SWaP optimization is really a tough problem, and if you aren’t careful, you can actually spend a lot of money miniaturizing a payload for the sake of getting it on a small sat,” Barnhart says. “You just have to look at the bigger picture. There may be a smaller price point of using a slightly bigger payload with a commodity small sat bus to accomplish your mission instead of pouring all of your resources into miniaturizing something. On the other hand, Lockheed has been asked specifically to miniaturize things for missions where smaller spacecraft are absolutely required. We have the critical thinking ability to work across the whole challenge area.”

Launch and supply-chain complications have also driven SWaP-optimization and cost-efficiency initiatives for small sats. Industry officials recall that scheduling a slot on a launch manifest used to be a cumbersome, expensive process.

“Launch costs have significantly come down over the years, and satellite bus production has somewhat commoditized in the sense that there’s more entrants,” Schmoll says. “Proliferated constellations are becoming achievable because they provide both commercial and defense the ability to launch a layered sensing capability or infrastructure at a much lower cost than when exquisite satellites had to be used.”

Recent supply-chain issues have also presented their own set of obstacles when aiming to ensure affordability and reliability in a small sat. Integrating trusted, secure microelectronics is often non-negotiable but can be expensive and difficult to acquire.

“Supply-chain limitations and uncertainty is the primary challenge,” Kirkendall says. “Critical components, like microelectronics for example, are supply-constrained and can have long lead times. Other examples of supply-chain shortages are electric propulsion propellant valves, plumbing, and regulators. When U.S. suppliers are required for military application, supply-chain issues can be even more of a challenge.”

Despite the impediments, excitement for what’s to come in the small sat industry continues to grow. The MDA, SDA, commercial companies, and the newly emerged U.S. Space Force are expected to work together in developing an overall strategy for how each entity’s respective technologies will play into each other beyond the atmosphere.

The future of small sats

Economic viability, as Kirkendall says, is motivating small-sat maturation and advancements. Small-sat suppliers are insisting that the key will be leaning in to the small sat’s trademark diminutive size.

“We started driving smaller and smaller to try and get the launch costs down, and we’ve kind of settled on some standard size platforms,” Young says. “Now, we’re working toward getting more capability and mission-enabling technologies into those form factors with whatever form factor is appropriate for the mission.”