Getting to Space Faster with EMA Simulation and Measurement

The fourth industrial revolution is here, and the space industry is leading the way, increasing the need for space environment simulation and measurement. The Brookings Institution describes the fourth industrial revolution as the combination of technologies integrating the biological, physical, and technological spheres to transform economic, political, and social systems. The institute says that better technology and decreasing costs have made outer space more accessible than ever before, including to private companies, making accurate space simulation and measurement a smart business decision.

More than 10,000 private space companies, 5,000 large investors, and 130 state organizations comprised the global space industry as of 2021. As public interest continues to grow, Morgan Stanley estimates that the global space industry could generate more than $1 trillion in revenue in 2040. That is up from $350 billion currently.

Getting off the ground is no easy task. To ensure that the spacecraft and components can handle the harsh space environmnt, we have to complete testing. Ground-based testing, which was time-consuming, historically has been performed. However, with the proliferation of space this method has had difficulty keeping up with the advancement of industry.

“The time frame of a lot of the previous testing has been on the order of years or even decades,” EMA PhD. Senior Scientist Gregory Wilson says. “However, with the industry, it’s on the order of months and so because of that a lot of testing was foregone, which can lead to instances and circumstances when spacecraft have failed.”

EMA is available to anyone looking to learn more about the effects of the space environment on equipment. Our technology predicts how to prevent fundamental flaws, significant risks, and creates better designs on your timeline.

“One of the major goals of our lab is to not only facilitate that testing by combining all the different complex factors of the space environment, but also to do it on the same time frame that industry is running at, not in years, but in months and weeks,” Wilson says.

The Space Environment

Fig. 1. The FAA defines space as starting 81 miles above Earth’s surface.

Before you can start to think about heading to and testing in the space environment, you have to understand what space is. The FAA defines space as the altitude where an object will remain in orbit, even if it’s just for a day or two, before the upper atmosphere drags it back to Earth. This is typically 81 miles above the Earth’s surface.

Outer space is a harsh environment with several hazards that must be accounted for during the design process. This includes:

  • Gravity
  • Earth’s atmosphere
  • Micrometeoroids
  • Vacuum
  • Radiation
  • Charged Particles

Electromagnetic Effects

We describe space as a near vacuum since there is still material present. At an altitude of 596 mi there are about one million particles per cubic centimeter.  This near vacuum creates three potential problems for spacecraft: out-gassing, cold welding, heat transfer.

The main electromagentic (EM) focus here is on out-gassing. Some materials used to build spacecraft can trap tiny bubbles of gas while under atmospheric pressure. These materials are typically composites such as graphite or epoxy. When the spacecraft experiences less pressure in the vacuum of space these gasses escape. This process is called out-gassing. These gases have the potential to coat sensors and lenses and cause electronic parts to arc. This arcing can be disastrous. This is one reason why materials must be carefully selected and tested before heading into space.

The sun puts out EM radiation and since there is no atmosphere to protect spacecraft it is more vulnerable in orbit than on Earth. This can lead to several problems such as heating on exposed surfaces, degradation, and solar pressure.

Prolonged exposure to ultraviolet (UV) radiation can degrade, or damage surface materials and electronics. This radiation is the reason why materials need to be hardened, or shielded, to survive the space environment. Determining how materials will perform and if they need to be hardened is essential to consider in the design process.

Fig. 2. Solar flares send charged particles

Charged particles could be the most dangerous part of the space environment. The primary sources for these particles are solar wind and flares, Galactic cosmic rays, and the Van Allen radiation belts. These charged particles are often tied together with EM radiation because their effects are similar. No matter where charged particles come from, they can harm spacecraft in several ways including charging, sputtering, and single-event phenomenon (SEP).

Spacecraft Charging

Spacecraft charging is when charges build up on parts of the spacecraft as it moves through highly concentrated areas of charged particles. When charges are built up, they can discharge at any time. These discharges can have catastrophic consequences, leading to damage on surface coatings, degradation of solar panels, loss of power, and switching off or permanently damaging electronics.

Sputtering can result in wear and tear in spacecraft components. This happens when charged particles move at a high-speed hitting the spacecraft, similar to sand blasting.

Focusing on these challenges in the design process helps get spacecraft into space faster and also gives manufacturers peace of mind that their product is not going to fail. EMA plays a role in mitigating these risks by combining simulation using Ansys Charge Plus and measurements in the state-of-the-art Space Environment and Radiation Effects (SERE) commercial test chamber.

Space Environment Simulation

Fig. 3. Example of a satellite simulation in Ansys Charge Plus.

EMA starts the space measurement process with simulation and analysis. Once simulation is complete, targeted testing can begin.

“By merging both simulation and testing, you’re able to not only save time, but also save money and potential costly mistakes that could be done simply focusing on one or the other,” Wilson said.

We use Charge Plus to do the simulation. The software uses a multiphysics approach to simulate charging and discharging phenomena. The time-domain solvers can simulate:

  • Electric arcing
  • Material surface and internal charging
  • 3D particle transport
  • Dielectric breakdown
  • Excessive charge build up
  • Material degradation
  • Surface flashovers
  • EM interference
  • Plasma wake

Fig. 4. Plasma wake results as shown in Ansys Charge Plus

Charge Plus allows users to not only get a closer look at complex behaviors in the space environment but also the different space environments that exist.

“The low Earth orbit is far different than the GEO for example,” Wilson says. “The densities and plasma and the different currents change drastically the type of charging that’s observed, but also the type of situations that you need to be aware of.”

Charge Plus integretes with Ansys Discovery for a single workflow. Users are able to process the CAD, prepare the simulation, and run it right in the software.

“From there you can run different environments, you can run it with the different tool sets,” Wilson said. “Whether you’re trying to do just analytic environments or looking at particle-in-cell codes, we also have the ability to go even further beyond that.”

Space Environment Testing

Fig. 5. EMA Space Environment and Radiation Effects testing chamber

We use the SERE commercial testing chamber to do targeted testing on a particular design after proper analysis. SERE is capable of charging, radiation, and aging investigations.

“It’s important to do these radiation and charging studies on Earth so that you don’t run into any cataclysmic issue when you send your satellite up in space,” said EMA Staff Scientist Brian Wood. “You can kind of gauge and mitigate any risk.”

Testing with SERE

Each testing project is different and catered to each customer. The SERE team will start by identifying the issue and the anticipated problems.

EMA will collect all the materials and create custom mounts and cabling inside the SERE chamber. The team will discuss the radiation exposure level and start testing.

Fig. 6. SERE radiation source (left) and a look inside SERE (right).

EMA has mounted materials on the door side of the SERE chamber. It comes with a 24-inch sample plate and is approximately a cubic meter in volume. In about a day, SERE can pump down to 10-8 Torr.

You can find the instrumentation  on the other side. This includes an electron flood source, low plasma generator, and VUV Krypton arc lamp.

“We have the UV photon source to do neutralization and any aging studies,” Wood said. “Then we have the plasma source which can recreate the LEO (low Earth orbit) environment. With those we’re essentially able to mimic many of the environments that a satellite can be exposed to when it’s up in space.”

Once testing is complete, the SERE team will write up a report with its findings. You can find more detailed information about what capabilities SERE has by clicking here.

Benefits of EMA

EMA offers a one-of-a-kind experience for those looking to head to space by offering both simulation and measurement services. Wilson says that both space measurement simulation and mesurement require expertise, but most companies only focu on one of them, leading to oversight in both areas.

“If you only look at the simulation side you may miss certain factors that lead to inaccurate results,” Wilson says. “If you’re just look at testing, you’re not necessarily looking at the full picture.”

Another aspect that makes EMA stand out is that we are a commercial company working for you and on your timeline.

“We’re available and we have the expertise to do unique testing… you know there are other places that do this, but we accomplish it faster and we do it, I think, more reasonably,” Wood said.

Since EMA is working on your timeline, we are your single point of contact for the entirety of a project.

“A lot of times in companies they go through the design phases and then once the design phase is completed that person or group often is tasked and moved on to another project or an entirely different disciple,” Wilson said. “We are able to retain a consistent perpetual experience and knowledge base that helps us remain as experts and leaders of the field.”

Start your space environment simulation and measurement journey with us by clicking here here. We are eager to help you achieve your goals.