Cold SMA helium gas actuator

Actuator for use on the Rosetta mission to the planet Wirtanen. Ptolemy, a gas analysis instrument to be flown on the Rosetta Lander, is produced in collaboration between RAL Space Science and Technology Department and the Planetary and Space Sciences Research Institute at the Open University, UK. It includes two tanks of helium which will be needed 8 years after launch when the spacecraft reaches the comet Wirtanen. The actuator opening and releasing the helium is made of shape memory alloys (SMA). Here can be seen the actuator in its ‘cold’ state before being heated to snap off a frangible pillar through which the helium can flow.