The era of private spaceflight gets off to a promising start
One entirely new trend that has emerged in the 21st century is the commercialization of spaceflight. A Falcon 9 rocket built by the SpaceX company was launched successfully on 30 May 2020. It carried NASA's Crew Dragon vehicle (also developed by SpaceX) to the ISS: a highly prestigious success – especially for Elon Musk, who made it possible for manned space missions to take off from American soil again for the first time since the end of the space shuttle era almost ten years ago. Other commercial enterprises across the globe have also positioned themselves to pursue new technological approaches or promote space tourism.
Furthermore, 2020 is the Year of Mars: no less than three missions are being launched to the Red Planet, regarded as one of the most interesting objects in the solar system because it is relatively similar to our Earth. However, a window for the fastest journey to Mars only occurs once every 26 months, via what is known as the Hohmann Transfer Orbit. NASA is already aiming to send its fifth mission to Mars with a rover and is testing new landing maneuvers, while China will be launching its first mission to the planet with a rover on board. The most surprising development is surely the involvement of the United Arab Emirates, whose space agency was founded a mere six years ago. Its mission named “Al-Amal” (or “Hope”) initially aims to send a space probe into orbit around Mars.
High-precision measurement technology for reproducible results
How is Kistler supporting all these efforts? Let's take a look at the portfolio of measurement solutions available from the Kistler Group, and see how they can provide support for spaceflight programs in actual practice. Kistler's solutions cover several fields:
- Rocket engine tests
- Environmental simulation and payload tests
- Load/stress and lifetime tests
- Additional special applications (micro-vibrations, vacuum chamber tests)
Reaching space means attaining an altitude of at least 100 km above the Earth's surface, and high-power rockets are the only way to achieve this. Force sensors and dynamometers from Kistler are deployed to determine engine power and shear force. Pressure sensors and accelerometers that guarantee stability at high temperatures are also used to detect combustion instabilities in test mode. These instruments are based on piezoelectric quartz elements grown by Kistler itself: they can withstand temperatures of up to 700°C, or even up to 1,000°C for short periods.
Kistler also offers piezoresistive solutions for static pressure monitoring – to monitor filling levels, for example, or to measure the pressure in supply lines to the engine. All the solutions described here are essential to ensure reliable and reproducible operation.
Once a reliable carrier rocket is available to leave the Earth's field of gravity, the next question is: how can a payload be transported reliably into orbit, or even further into space? To send a satellite into orbit, for instance, extensive environmental and load tests need to be performed. This is because the payload is sometimes exposed to very high mechanical stress and other loads during the launch and in flight. Here too, Kistler offers the right instruments for the job – such as rugged accelerometers to measure vibrations. All the components on board for the voyage into space must also be light, robust and compact – every extra kilogram generates costs that run into four digits. Another critical factor here is low outgassing throughout the measuring chain: this is essential, because deposits can severely compromise equipment and applications.
Innovative solutions for special applications
For test-stand payload investigations such as force-limited vibration testing (FLVT), it has proven beneficial to use force sensors and load cells that prevent overtesting – damage due to excessive resonance-induced vibrations. Appropriate piezoelectric force sensors from Kistler configured in a special ring structure even make it possible to set up a closed control loop to adapt the acceleration for the shaker in the environmental simulation.
Last but by no means least, Kistler develops high-performance dynamometers: one example is the 9236A, which combines maximum natural frequency with high sensitivity and measurement accuracy thanks to its new ceramic top plate. In satellite-based camera equipment, for instance, preventing micro-vibrations and jitter can significantly improve the quality of high-resolution images.
To support engineers as they develop technologies that can master the challenges of spaceflight, Kistler offers an extensive range of additional solutions for applications such as cryogenic testing. The entire portfolio is backed by Kistler's decades of experience and its worldwide presence. No matter where on our planet they operate, customers benefit from valuable support for their spaceflight programs: to complement its outstanding measurement products and solutions, Kistler offers development partnership, technological consulting, and local service.