SPACE
By 2040, the global space economy is poised to shatter the $1 trillion mark, enticing a flurry of electronics manufacturers into the cosmic marketplace. However, when confronted with the rigorous challenges of rocket launches and the harsh confines of space, how does one orchestrate ground-based simulations to ensure the flawless operation of their products in orbit?
Satellites can be classified by their orbital altitudes into Low Earth Orbit (LEO, <2,000 km), Medium Earth Orbit (MEO, <10,000 km), and Geostationary Orbit (GEO, ~35,800 km) (Figure 1). Their weights vary from a few kilograms to several hundred kilograms. In recent years, SpaceX’s Starlink LEO communication satellites have been commercialized, initiating a new space economy model.
Additionally, CubeSats, which have relatively low manufacturing costs, have become a popular entry point for satellite technology research. The satellite industry chain is becoming increasingly mature, and the reduction in satellite launch and manufacturing costs is creating significant business opportunities in space. This, in turn, increases the demand for electronic components, encouraging many companies to gear up for entering the space market.
Traditional space-grade electronic components come with a hefty price tag, and some parts are challenging to acquire due to various countries’ regulatory policies. In contrast, Commercial Off-The-Shelf (COTS) electronic components, such as those used in computers, mobile phones, and automobiles, are relatively affordable, perform well, and are readily available. In recent years, utilizing COTS components for space missions has become a popular trend.
What verification tests are required for COTS electronic components to be deployed in space?
The Impact of Rocket Launch on Electronic Components
1. Vibration Testing
When manufacturing and assembling satellites on the ground, factors such as temperature, humidity, and dust contamination must be considered. Once assembled, the satellite is launched into space aboard a rocket, initially enduring the intense vibrations of the rocket launch.
Vibration testing machines can simulate rocket launch conditions on the ground, performing vibration tests in both vertical and horizontal directions. Different rockets have varying vibration levels. For example, the vibration test parameters for the SpaceX Falcon Heavy rocket include vibration frequencies ranging from 10 to 2,000 times per second and gravitational accelerations up to several tens of times. Vibration testing can be used to verify that the satellite or its electronic components can still function normally after the launch process.
2. Acoustic Testing
The rocket launch process also generates acoustic noise, which can particularly affect large and thin components such as solar panels and antenna panels. Acoustic noise may cause these components to crack, suffer structural damage, or malfunction.
An acoustic chamber is used to simulate the acoustic noise generated by the rocket. During testing, liquid nitrogen is vaporized, causing its volume to expand hundreds of times instantly, producing immense pressure. This pressure is then converted into sound waves via speakers, which are directed into the acoustic chamber to test the satellite or its components.
3. Shock Testing
When the rocket leaves the ground and reaches a certain altitude, the rocket stages begin to separate one by one, and then the fairing opens to release the satellite into orbit.
These processes generate shocks, which pose severe tests for the solder joints, chips, and other brittle materials of the satellite’s internal components.
Therefore, shock testing must also be conducted on the ground to understand the satellite and its electronic components’ tolerance to significant shocks.
4. Electromagnetic Compatibility Testing (EMC)
Due to the concentration of various electronic components within the confined space of the rocket, electromagnetic interference between the satellite and the rocket may affect the mission.
Therefore, before launch, the satellite must undergo Electromagnetic Compatibility Testing (EMC) to ensure that the electronic components used in the satellite do not interfere with each other or with the rocket.
How Does the Space Environment Affect Electronic Components?
1. Thermal Vacuum Cycling Test
Low Earth Orbit (LEO) satellites travel at a speed of seven kilometers per second, completing an orbit around the Earth every ninety minutes. As these satellites orbit in a vacuum environment, they face significant temperature challenges.
When directly exposed to sunlight, the satellite’s temperature can soar to 120 degrees Celsius, whereas when it is away from the sun, the temperature can plummet to -120 degrees Celsius. Moreover, the vacuum environment can cause electronic components to overheat due to poor heat dissipation. The low pressure of the vacuum can lead to material decomposition, cavity leaks, or outgassing, which results in contamination.
The Thermal Vacuum Cycling Test can simulate the vacuum conditions and temperature fluctuations of the space environment. During the test, the satellite or electronic components are placed in a vacuum chamber with extremely low pressure. The equipment then uses radiation and conduction methods to raise and lower the temperature of the satellite or electronic components to mimic solar exposure. During this process, the satellite or electronic components are powered on and operating, with their functionality being continuously monitored to ensure they perform correctly. Thermal vacuum cycling tests usually last for a week or even longer, and they are a common cause of failures in satellites and electronic components.
2. Radiation Testing
In the space environment, electronic components are directly exposed to radiation without the protective shield of the Earth’s atmosphere. In Earth’s orbit, the radiation environment includes the Van Allen Belts, Galactic Cosmic Rays (GCR), and Solar Energetic Particles (SEP).
These radiation environments are filled with a high density of electrons, protons, and a small number of heavy ions, which can cause data upsets, system crashes, and even permanent failures if they strike satellite electronic components. The operational lifespan of satellites in orbit can vary from a few months to several decades. The longer a satellite remains in orbit, the greater its susceptibility to radiation-induced effects.
Therefore, electronic components used in space environments are inevitably affected by radiation and must undergo radiation testing to assess their characteristics before being sent into space. COTS electronic components typically possess some level of radiation resistance, but their radiation tolerance must be evaluated through testing to ensure suitability for space mission requirements.
The Final Milestone for Electronics to Ascend to Space Components
COTS electronic components must undergo “launch environment testing” before being sent into space, including simulating the vibrations, acoustic noise, shocks, electromagnetic compatibility testing, as well as thermal vacuum cycling and radiation testing in space (more testing items are not listed here one by one). After passing these tests, it is even more important to obtain “flight heritage”. By launching the product into space and successfully executing various missions, the more flight heritage obtained, the higher the value of the product. The space industry attaches great importance to flight heritage, which serves as the best guarantee for the product.
iST is Asia’s most comprehensive third-party laboratory for space environment testing. In 2019, iST collaborated with the National Space Organization (NSPO) to promote the development of Taiwan’s space industry. Since joining the Taiwan Space Radiation Environment Testing Alliance in 2021, iST has completed radiation tests for various electronic components, including analog, digital, memory, RF, and power devices. iST continues to enhance its space environment verification and testing capabilities, offering one-stop services. Through professional specialization, iST assists domestic and international manufacturers in conducting space environment tests, allowing them to focus more on product design and manufacturing.