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21-784: TinyOS has been used in space, being implemented in ESTCube-1 . TinyOS applications are written in the programming language nesC , a dialect of the C language optimized for the memory limits of sensor networks. Its supplementary tools are mainly in the form of Java and shell script front-ends. Associated libraries and tools, such as the nesC compiler and Atmel AVR binutils toolchains, are mostly written in C. TinyOS programs are built of software components , some of which present hardware abstractions. Components are connected to each other using interfaces . TinyOS provides interfaces and components for common abstractions such as packet communication, routing, sensing, actuation and storage. TinyOS

42-530: A Deferred Procedure Call and interrupt handler bottom halves. A TinyOS component can post a task, which the OS will schedule to run later. Tasks are non- preemptive and run in first in, first out order. This simple concurrency model is typically sufficient for I/O centric applications, but its difficulty with CPU-heavy applications has led to developing a thread library for the OS, named TOSThreads. TOSThreads are unmaintained and have been deprecated. TinyOS code

63-594: A cost-effective way of lifting a rocket into the stratosphere. The method is considered to be safe and could reduce the carbon footprint of future rocket launches, whereas in the past, emissions alone had terrible implications for the climate. Janhunen has proposed a lighting solution for an O'Neill Cylinder . According to this concept, sunlight is concentrated by cylindrical paraboloid concentrators and reflected by semi-toroidal and conical reflectors and controlled by local blinders to simulate Earth-like diurnal and seasonal illumination cycles. Janhunen has also conceived of

84-433: A frequency of 437.505 MHz with a 9600 baud connection speed and AX.25 packet standard is used. The relatively slow connection speeds result from the use of amateur radio frequencies which limits the bandwidth to 25 kilohertz. The fast connection is used only when the satellite has been given a specific order. Both telegraphy and packet telemetry protocols of ESTCube-1 are published on project webpage. Commands sent to

105-499: A mass of 1.048 kg. The mission ended officially on 17 February, 2015, and it was said that during this time it resulted in 29 bachelor's and 19 master's dissertations, 5 doctoral theses and 4 start-ups. The deployment of the E-sail tether was unsuccessful, and thus no measurements were taken of the E-sail or of the plasma braking deployment system. The last signal from ESTCube-1 was received on 19 May, 2015. Developed as part of

126-533: A startup company operating in the space sector. Janhunen studied theoretical physics at the University of Helsinki and earned his Ph.D. in space plasma physics simulations in 1994. He has also published a theory on the origin of multicellular life. Janhunen is best known for his electric solar wind sail invention. Janhunen's electric sail could enable travel at speeds of up to 100 km/s in space without any fuel consumption. With no major problems in any of

147-437: A two-sphere dumbbell configuration design of a rotating settlement for a first-generation in-space habitat settlement. Built in the orbit of the dwarf planet Ceres , Janhunen's megasatellite structure would consist of numerous cylinders, each many kilometers in size. They would be mounted on a disc that is lit from above and below by sun mirrors. Ceres would supply the materials for the construction. According to Janhunen, Ceres

168-522: Is also set in CubeSat standard, the highest possible mass for 1U CubeSat is 1300 grams. Communication from the satellite was made at two International Amateur Radio Unions registered frequencies Periodic but very slow communication was made by using 18 WPM telegraphy signal on a frequency of 437.250 MHz. At that frequency, the most important satellite parameters are returned every 3 to 10 minutes. For fast connections FSK-modulation radio signals on

189-480: Is an associated member of ESA, most of the launch expenses (about 70,000 euros) were covered by the Estonian member fee for educational expenses. With the launch, total expenses for the project were approximately 100,000 euros. The satellite successfully demonstrated the operation of the systems in space, with a two-year operational life. The deployment of the E-sail was unsuccessful, and no measurements were taken of

210-592: Is fully non-blocking : it has one call stack . Thus, all input/output (I/O) operations that last longer than a few hundred microseconds are asynchronous and have a callback . To enable the native compiler to better optimize across call boundaries, TinyOS uses nesC's features to link these callbacks, called events, statically. While being non-blocking enables TinyOS to maintain high concurrency with one stack, it forces programmers to write complex logic by stitching together many small event handlers. To support larger computations, TinyOS provides tasks, which are similar to

231-632: Is statically linked with program code and is compiled into a small binary, using a custom GNU toolchain . Associated utilities are provided to complete a development platform for working with TinyOS. TinyOS began as a project at UC Berkeley as part of the DARPA NEST program. It has since grown to involve thousands of academic and commercial developers and users worldwide. (list in reverse chronological order) As of 2010, three integrated development environments (IDEs) are available for TinyOS, as plug-ins for Eclipse : ESTCube-1 ESTCube-1

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252-401: Is the first Estonian satellite and first satellite in the world to attempt to use an electric solar wind sail (E-sail). It was launched on 7 May, 2013, aboard Vega VV02 carrier rocket and successfully deployed into the orbit. The CubeSat standard for nanosatellites was followed during the engineering of ESTCube-1, resulting in a 10×10×11.35 cm cube, with a volume of 1 liter and

273-489: The E-sail or of the plasma braking deployment system. Pekka Janhunen Pekka Janhunen is a Finnish space physicist, astrobiologist , and inventor. He is a research manager at the Finnish Meteorological Institute 's Space and Earth Observation Centre and a visiting professor at the University of Tartu , Estonia. He is also senior technical advisor at Aurora Propulsion Technologies,

294-661: The Estonian Student Satellite Program, ESTCube-1 was an educational project in which university and high school students participated. While emphasis was placed on educating students during creation of ESTCube-1, it did have a scientific purpose. The satellite carried an electric solar wind sail (E-sail), which was invented by Finnish scientist, Pekka Janhunen . During the ESTCube-1 flight, 10 meters of 20–50 micrometer thick E-sail wire, sometimes referred to as "Heytether," were to be deployed from

315-507: The satellite used the 145 MHz (2 meter) amateur band. ESTCube-1 microcontrollers use the following operating systems: Mission Control System is currently being developed by the students of Tartu University under the supervision of the company CGI Group . ESTCube-1 was launched as a secondary payload onboard Vega flight VV02 , the least expensive satellite launch offered by the European Space Agency . Because Estonia

336-517: The satellite. The deployment of the Heytether was to be detected by a decrease of the satellite's rotation speed or an on board camera. To control the E-sail element's interaction with both the plasma surrounding the Earth and the effect it had on the spacecraft's spinning speed, two nanotechnology electron emitters/guns were on board. The electron emitters were connected to the E-sail element which

357-537: The technical fields thus far, planning of the first test mission was reported to have begun, as per a 2008 ScienceDaily article. Janhunen received funding for his electric solar wind sail research from the Runar Bäckström foundation in 2005. Janhunen has proposed that steam balloons could be used to launch rockets and satellites from higher altitudes. According to the Finnish scientist, steam balloons are

378-547: Was also on board that was capable of making RAW-format pictures with VGA-resolution. This camera was used to acquire images of Earth and had been intended to monitor deployment of the Heytether. To complete the scientific experiment and communicate with the satellite on several occasions the orbit chosen was a Sun–synchronous circular orbit at an altitude of 670 kilometers. ESTCube-1 was launched into orbit by Arianespace , using Vega VV02 rocket which lifted off from ELA-1 at Kourou at 02:06:31 UTC on 7 May 2013. The satellite

399-409: Was placed into orbit and communication successfully established, with the first photo of the Earth taken on May 15, and transmitted to the ground on the amateur radio band. The plan, beginning with the 7 May 2013 launch, included the following steps: The mission ended due to degradation of the photovoltaic power system and subsequently the batteries became exhausted. The last official transmission

420-463: Was to be charged positively to 500 volts by shooting out electrons. The positive ions in the plasma were intended to push the E-sail element and influence the satellite's rotation speed. The effect of the plasma on the E-sail was to be measured by the change in said rotation speed. The tether had also been intended to de-orbit the satellite by use as a plasma-brake to demonstrate a possibility for returning small satellites from orbit. A color CMOS camera

441-502: Was transmitted on 17 February, 2015, however, imaging the Earth and gathering environmental data continued till May 19, 2015. The plan to test a solar sail the satellite carried failed since the sail cable unwinding mechanics did not survive the rocket takeoff vibration. During the development of the Estonian satellite mission it was decided to make a 1U CubeSat. By standard 1 unit (1U) CubeSat base side length must be 100.0±0.1 millimeters and satellite height must be 113.5±0.1 mm. Mass

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