Today, vacuum tests for the spheres and the micro pumps were carried out to test the volume changing capabilities of SAM’s spheres. In the finished structure the volume change between two neighbouring spheres will result in a shape change of the entire structure. For today’s test two inflatable spheres were connected by a micro pump (Bartels Mikrotechnik GmbH) and tested first at ambient pressure and then in the vacuum chamber. It can be confirmed that the pumps worked in vacuum conditions, but the volume change was too slow (especially by considering the short micro gravity time of the sounding rocket experiment of roughly 140s). Further research will be focused on increasing the flow rate or maybe changing to more powerful pumps. Thanks to the Strathclyde students Thomas Perry and Paul Hammond for getting the micro pumps ready for today’s test.