The first Finnish satellite Aalto-1 is about ready to be launched to space. During autumn, the satellite has undergone, for example, demanding vibration and shock testing performed by VTT Expert Services.
Testing plays an important role in ensuring that the work began already in 2010 and the expensive travel to space will not go to waste.
"We have tested the satellite's durability in different mechanical loading conditions. Testing has simulated the strong vibrations and shocks transmitted from the booster rocket to the satellite during launch and take-off", says Olavi Nevalainen, Product Manager at VTT Expert Services Ltd.
Testing will ensure that the satellite and its equipment can tolerate these stresses. For testing purposes, the satellite was mounted with acceleration sensors, which measured frequency responses of the satellite structure before the actual proof testing. The measurements were repeated after the proof tests.
On the basis of responses measured, it is estimated at which frequencies strong amplitude magnification (resonances) and damping (anti-resonance) occur in the structures. On the basis of measurement results from proof testing, an assessment is made on any potential changes in the structure, resonance frequencies or changes in their amplification coefficients.
The actual proof testing consists of strong sinusoidal vibration tests, random vibration tests and shock tests. The purpose of heavy sinusoidal vibration testing is to ensure that the satellite's attachments to its platform will hold. Random vibration simulates the strong mechanical and partly also acoustic vibration transmitted from the booster to the satellite. Strong shocks, with maximum acceleration rates exceeding 6000 m/s2 (600 g), are used to simulate the stresses during launch and take-off.
The satellite has been tested during various phases of its construction. The first tests were made already a year ago on the satellite's 'engineering model'. The latest tests on the actual flight model were made in March 2015.
Space travel costs 50,000 EUR/kg
A booster trip to space is not cheap. The voyage to the orbit at the height of 600 kilometers will cost approximately 50,000 EUR/kg. In other words, sending the 4-kg Aalto-1 into space costs some 200,000 euros. The satellite's projected launch will be in February-March 2016, and it will be launched by the U.S. company SpaceX.
Aalto-1 is an extensive joint project
Aalto-1 is a student satellite project that is led by the Department of Radio Science and Engineering at Aalto University. It is an extensive joint project with involvement from other universities and various space technology expert organisations, including VTT.
A spectrometer developed by VTT for space borne seasonal Earth observation will also travel to space with the satellite, as well as the RADMON radiation monitor developed by the University of Turku and Helsinki, and an electrostatic plasma brake developed by the Finnish Meteorological Institute.
Read more about the Aalto-1 project