Post Tue Jul 19, 2011 9:43 am

STRaND the world's first smartphone satellite

SSTL (Surrey Satellite Technology Limited) together with University of Surrey builds the first “smartphone” mission who will fly in space.
The new satellite called STRaND-1 or “Surrey Training, Research and Nanosatellite Demonstrator” wants to be an experiment which incorporates COTS components (commercial off-the-shelf) and will try to prove that a normal smartphone can be used in the un-favorable conditions outside the Earth’s atmosphere.

This is not the first experiment of this kind, if we recall the event from summer 2010 when a solar balloon built by a student team flew in the high atmosphere and succeeded to produce a series of spectacular pictures using a usual commercial camera. Also, in 2006, the Japanese mission Cute-1.7 succeeded to fly in space 2 electronic boards coming from normal PDAs.

It would be however the first time when a complete functional smartphone would be used in a LEO orbit.

SSTL has a long tradition in building small platforms and part as the market strategy permanently tries to push the limits set by the aerospace industry.
It should be said from start that from the technical point of view the new platform brings no major innovations but an eventual success would add an image capital to the British company and will open a niche on the nanosatellite experimental market which was dominated for a long time by the Cubesats.

The Cubesat platform is preferred today by the vast majority of the Universities for their educational programs, however they have major constraints for the technologies that can be incorporated- constraints imposed by the dimensions which push the limits of the miniaturization but which together with the cost cutting philosophy limit the possibility to choose the components.

The idea is simple. Today’s smartphones incorporate a lot of components and they reached the maturity, being able to execute almost all the operations a normal computer can do. The processors have surpassed the 1 GHz frequency barrier but at the same time they lowered the power consumption. The cameras have now very good resolutions, wireless or GPS are standard components in an actual smartphone. Also, due to the aggressive competition between companies, their cost is continuously decreasing and miniaturization went to extreme cotes reducing the weight and size. The market of smartphone applications is also very dynamic and brings considerable incomes every year being a factor which stimulates the development of this segment.

So, the question the designers of STRaND project have addressed – could a smartphone be operated successfully from space and could bring commercial benefits for the future – is absolutely justified.
Considering that the solar cell technology reached 30% efficiency, the MEMS (micro-electro-mechanical systems) are more and more present, the new nanosatellites seem ready to incorporate the smartphones of today.

How appears the new nanosatellite from the technical point of view?
STRaND is a 4kg nanosatellite, 30 cm cub shaped. It is a complete satellite incorporating all the classical systems despite the fact that SSTL claims it will not exceed the cost of a normal automobile.

It has an active flight control system- using reaction wheels and thrusters- and GPS sensors for determining the position.
What is new, as we said earlier, is that the spacecraft will contain a normal smartphone (costing some hundred euros) with a 1 GHz ARM processor and running the Android operating system. As everybody knows, this is an “open source” system and the engineers from SSTL will have to create an interface between Android and the satellite’s operating system, interface which should solve the communication problem between the two.

The three major tests the satellite has to surmount in space are the radiation dose, the temperature (which should remain within the normal allowed limits) and the launching characteristics (vibration or acceleration induced by the launcher).
The third one has been guaranteed through special intensive tests in the laboratory. For the first two engineers have placed the smartphone inside the spacecraft’s body hoping the special insulation will do most of the protection job.
The optics of the camera however, will not be obstructed but it will have a clear view of the Earth as seen from a LEO orbit.
The battery’s temperature will be continuously monitored and if decreases a special intensive computing software routine will be ran – forcing the processor to work at the full capacity and by that to overheat and to dissipate extra heat to the battery.

In the first phase the satellite will be operated in a classical manner- the onboard computer will be used for performing the satellite’s vital functions, but the smartphone will be used as a backup scientific instrument.
The onboard computer will execute the special activities necessary to operate the smartphone in space, it will collect the data from it, it will monitor it and it will send it to the ground station as telemetry.
In the second phase of the mission, if everything goes smoothly and if the processor of the smartphone proves to be reliable enough and stable, it will take the lead for flying the spacecraft. The onboard computer will go in stand-by and all the functions will be executed through the smartphone.

As we said at the beginning of the article, SSTL does not bring any technical progress with this application but it gains a huge image capital and can attract considerable amount of money on the future from this kind of missions, in the perspective of an increased interest for space access and adjacent technologies in the past years.

SSTL has a long tradition in the small satellite segment. This tradition begins in the early 70s with the founding of a small research group, consolidated later in 1979 with the establishment of SSC (Surrey Space Center) in the Surrey University, continues in 1981 with the separation from the academic world and the establishment of the company (1985) and goes to present when SSTL has a list of 34 launched satellites and another 7 in development. The company with the base in Guildford, UK, and which has today 300 employees (and another 80 collaborators/researchers in the university) has been bought in 2008 (99% of the shares) by the EADS Astrium, the University of Surrey keeping only a symbolic part of 1% from the shares. Since then, as part of a new management strategy, to ensure the mark of the company as a global actor, SSTL owns also a subsidiary in US – Surrey Satellite Technology LLC with the central office at Denver/Colorado.

SSTL has production, integration and testing facilities, its own commanding centre and since 2006, when it bought the SIRA Electro-Optics company, its own optics department.

During the collaboration with the academic world we mentioned before, SSTL managed to build some advanced technologies used to fly the “University of Surrey satellite” UoSAT-1 in 1981, UoSAT-2 in 1984 (both built and launched with NASA support) series continued latter in the 90s with the platforms 3,4,5 and 12, or SNAP-1 (Surrey Nanosatellite Applications Platform) in 2000. Other experimental programs which should be mentioned are PalmSat and PCB-Sat.

SSTL has also some research projects ran together with the big space agencies as NASA and ESA.
Romania is also involved in 2 student space programs: ESEO and ESMO.
ESEO or European Student Earth Orbiter is the third satellite developed within the “Education Satellite Program” a microsatellite intending to capture Earth images from a LEO orbit, to measure the level of radiation and to test new space technologies (a star camera and a new type of reaction wheels).
ESMO or “European Student Moon Orbiter” will be the first educational satellite sent to the Moon, with a technology inspired by the one of Smart 1, and the fourth satellite from the “Education Satellite Program”.
In both missions, sponsored by ESA, SSTL has the leading role of the university consortium and should coordinate the activity of collaborators and to report back to ESA the actual situation/ the progress of the project.

Credit SSTL