Satellites are big, really big, are they not? This may be a leading question. Satellites can be huge, but they don’t have to be. At NTNU, a group of students is designing and constructing their own satellite. This satellite is small, very small. It is a CubeSat, which measures only 20x10x10 cm^3. This is tiny compared to for example the now defunct environmental monitoring satellite Envisat which is on the size of a London double-decker bus.
So why care about so small satellites? By the end of 2014, Science Magazine published their list of the most interesting scientific topics of 2014. On this list, the tiny CubeSats got their well-deserved place. CubeSats are becoming more useful and are used for education, science, research and technology development. As the electronics all of us are using improves and is getting smaller all the time, smaller satellites can now take on some of the tasks the big satellites used to do. For example, they can test a new scientific instrument, test a new communication device, investigate how bacteria thrives in micro gravity and so on. Although CubeSats can do a lot, they can’t do everything. For instance, Telenor still need the big ones to provide you with HD TV signals through your satellite dish.
Currently, the NTNU Test Satellite (NUTS) project and NUTS Facebook lets around 15-20 students study and actively work with space technology every semester. Students from electronics, cybernetics, computer science, mechanical engineering, telematics and physics have participated in the project. So far, 45 students have written their master thesis on NUTS-related topics since 2010. This gives the students experience in teamwork, similar to working in the industry.
In addition to the technical skills the students gain, they also get to enhance and broaden their experience by participating at international conferences in addition to annual workshops at Andøya where we get a glimpse of both international and national space industry. Knowledge about space and space technology is important as this is a growing industry, both internationally and nationally.
Norway has launched a series of small satellites the last five years http://www.romsenter.no/Bruk-av-rommet/Norske-satellitter with more to come.
Right now, we are finishing the prototype designs of the most central components of the satellite, some of it shown in Figure 2. Most of the electronics is designed and made by the students. You know, we could have bought it off cubesatshop.com, but we decided to learn more by building both the electronics and a novel carbon fiber structure for our satellite.
It takes time to design and construct a satellite. If you have greater aims than just to launch an Android phone or an Arduino into space, it is not possible to build a satellite in one or two semesters. Because of this, the design has been improved many times by new student teams.
“So, what will your satellite do!?” This is perhaps the most common question when we talk to people about the satellite. This question is both simple, but also very difficult. We are aiming to take send back pictures of the Earth, just as for example EST-Cube has done. This is cool. However, it is even cooler that we will be able to test our own electronics, our own radio systems and our own ground station to communicate with our own satellite.
Even if our goal is to get back a picture from space, just receiving a small “blip” or ping from the satellite will mark a great achievement. The space environment is harsh. The satellite will experience an ever changing temperature environment and it will be exposed to radiation when it is in orbit. During launch it must survive stress and vibrations from the rocket. All of this poses firm demands on how the electronics and software for the satellite must be designed and implemented. For example, one failing component must not be allowed to make a second component fail.
All this is driving us forward, and we are determined in our dream of putting our “knowledge in orbit”.
This blog entry was written by PhD candidate Roger Birkeland – NTNU, Department of Electronics and Telecommunications.