Engineering a New Approach to Satellite Constellation Design

Satellite propulsion systems have traditionally been designed for high reliability over large-scale production. Engineered for specific, high-stakes missions, these systems are produced in limited quantities — often only a few dozen units or less. Today, the advent of Low Earth Orbit (LEO) satellite constellations is changing this dynamic, ushering in new commercial and military opportunities that involve deploying hundreds or thousands of satellites designed for research, telecommunications, and Earth observation applications.

Small (under 500 kg), low-latency, and deployed as swarms with the same purpose and shared control, these units must be quick and economical to develop and launch. It’s a strategy that represents a big shift in satellite development: Propulsion systems that were once crafted in very limited quantities now need to be manufactured by the thousands. This scale-up necessitates a new design and development approach that blends modern manufacturing principles with legacy systems.

Defining the Challenge: Balance of Quality, Cost, Timelines, and Volume

Traditional space technologies are known for their exceptional quality, made even more valuable with the validation of successful spaceflight. Yet their accordingly low production volumes, long development timelines, and high costs pose a significant challenge. These factors simply do not align with the development pace and budget requirements of constellation innovators. Lower-cost materials can be found from alternative sources such as industrial component manufacturers or hobby rocketry firms; however, their associated levels of quality are insufficient to meet the stringent requirements for satellite components.

Neither approach solves the challenge. Further, it’s inherently risky for constellation developers to begin their design process with cheaper, non-heritage components and work to improve quality throughout the development process. Ideally, a more strategic approach involves leveraging proven quality components while exploring ways to reduce costs elsewhere.

Design Trades Add Value with Limited Impact on Performance

New space developers may be able to sacrifice some mission capability in order to prioritize cost and schedule. For example, by springboarding propulsion systems early in the development cycle, satellite engineers can determine what performance metrics trade best against mission requirements. Because planned constellations routinely consist of hundreds or even thousands of satellites (in contrast to a dozen or less on a legacy program), a single-unit failure has minimal impact on their operational success.

Determining design trade-offs early in the development process is critical and requires deep partnership between system developers and component suppliers. This invites closer examination of how systems will actually be used and opens the discussion as to whether slight reductions in performance parameters could be acceptable. Collaboration can lead to minor adjustments that improve cost-effectiveness without substantially affecting performance. The same cooperative approach can also help redefine production techniques, facilitating cost reductions and scalable manufacturing.

Design for Manufacturing has Impact on Space Components

Heritage components commonly rely on complex machining and assembly processes, made more complicated and costly due to multiple manufacturing steps and high precision operation. Through collaborative efforts and the adoption of new technologies, these components can now be produced using fewer or even a single machine. This requires heritage developers to work closely with a new group of suppliers, applying Design for Manufacturing (DFM) principles that drive retooling to optimize machine operations for cost-effectiveness. Assembly can be further simplified via reduced number of parts and fewer assembly steps, namely welding.

The resulting streamlined operations not only simplify production but also allow for the mass production of spaceflight-qualified parts. Significant economies of scale are immediate; parts can be produced quickly and be readily available for integration as building blocks used in a range of modular propulsion system designs.

Accelerating Development with Modular Subsystems and Heritage Technologies

A manifolded configuration of an electric propulsion system provides an example. Recently developed by Marotta Controls, the design integrates existing heritage products as part of a new electric propulsion system tailored for LEO constellation use. The manifold features an adaptable design depending on customer needs. The manifold can be configured with a pressure-reducing valve design or a proportional system using bang-bang pulse control solenoid valves. The Marotta RV001 is used as the mechanical regulator valve, which was specifically developed for satellite constellation electric propulsion applications using krypton or xenon media. For isolation and pulse control, Marotta PLV015 solenoid valves are used; originally designed for pairing with the RV001, the solenoid valves have been adapted to function as primary bang-bang pressure regulating valves.

This system operates in contrast with chemical propulsion, employing noble gases like krypton or xenon at very low flow rates. Gases move through small, pinhole-sized openings, enabling highly precise adjustments and station keeping. The design process utilized Marotta’s broad range of spaceflight-qualified components and heritage performance data; as a result, designing to component capabilities and system specifications required only minor modifications. Any additional subcontractor components chosen for use were commercial-off-the-shelf elements that offered the same seamless integration and light modification.

Increasing Flexibility to Enhance Manufacturability

The manifold design illustrated here reduced complexity and associated assembly time, while offering the flexibility to be configured as either mechanically regulated or bangbang pulse-controlled. Machined from a single piece of aluminum, it incorporates all necessary flow paths and connections. These design attributes improve the efficiency and ease of manufacturability, similar to other valve bodies produced by Marotta.

This design achieves high performance at low cost through simplified components and a focus on manufacturability. Part count is minimized, common components are prioritized, and assembly processes consider how to reduce complexity. Using only seven machined parts, the RV001 regulator offers an adjustable setpoint and high turn-down ratio in a compact, light, and cost-effective package. The PLV015 solenoid valve includes five machined parts, integrating a filter and optional latching mechanism to further enhance system functionality and reliability.

Balancing Cost, Quality, and Heritage Technologies in Satellite Constellation Strategies

The unique challenges of space — zero gravity, thermal extremes, and a spectrum of environmental contaminants — can increase development costs for any equipment destined to perform in space. Satellite constellations must withstand these rigors, while developers must balance their need for quality with timely and cost-effective manufacture of critical parts. Legacy space flight innovations, pivotal in historical missions like Moon landings and deep space exploration, now underpin modern constellation strategies — although their application must adapt to new methodologies.

Heritage expertise, collaboration, and access to detailed product data equip system providers to strategically refine component design, maintaining high quality as a cornerstone even as the industry seeks new, cost-effective methods to quickly expand LEO systems. By employing modular concepts, developers can harness existing capabilities to enhance or expedite propulsion systems, even while emphasizing simplicity in manufacturing through DFM processes and principles.

This article was written by Brian Ippolitto, Senior Director, Business Development of Space Business Unit, Marotta Controls, Inc. (Montville, NJ). For more information visit here  .

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