Juice magnetometer boom

In 2022, the European Space Agency's JUICE (JUpiter ICy moons Explorer) probe is expected to launch to Jupiter and its moons. Its main task will be to explore the icy moons Ganymede, Europa and Callisto. The nearly 5-tonne spacecraft will include a sensitive magnetometer, which must be positioned nearly 9 m from the spacecraft body for measurements. To do this, a mechanism called JBOOM - an arm made up of three segments - is used to hold the magnetometers in a folded position for launch under the Ariane 5 rocket's cover and to move the magnetometers to a position further away from the spacecraft at the right time in orbit.

A consortium of Frentech Aerospace, L.K.Engineering, VZLU, 5M and Serenum proposed a carbon composite solution powered by "artificial muscle" - an alloy wire with shape memory - for the tender. Compared to conventional electric motor or spring drive, SMA (shape memory alloy) wire has several advantages - mechanical simplicity, which contributes to higher arm reliability, programmability and very low shock, which sensitive electronic devices will appreciate. The disadvantage of SMA can be sensitivity to high temperatures, which has been solved by placing the motorization inside the carbon fibre composite profiles.

The Czech JBOOM will not be on the JUICE probe after all, but the European Space Agency ESA found the concept so interesting that it supported the continuation of the development project until the qualification of a demonstrator with the same dimensions as the real JBOOM. Currently, the Czech real-size JBOOM has successfully passed vibration tests at the European Space Agency's ESTEC centre in the Netherlands and functional tests. The experience gained during development will thus enable the application of the technology to future European space missions. Frentech and LKE are already working for ESA on a demonstrator of solar panels that can be opened using "artificial muscles".