A novel sensor for projectile detection in a multishot railgun

A railgun consisting of a projectile storage unit and a main launcher permits a repetitive acceleration of projectiles. A sensor placed in the main launcher ensures that the loaded projectile reaches its designated position prior to launch. Furthermore, triggering the railgun energy units by this sensor excludes the possibility of energy supply without projectile presence and raises the repetition rate in addition. Systems like laser barriers or off-the-shelf switches are natural choices. However, several experiments performed at the multishot railgun RAFIRA testing these detection systems have evidenced that they are not suitable for this job. The limitations these sensors revealed are most likely caused by plasma clouds and hot gases going along with the plasma as well as of metallic wear debris and smoke. Therefore, a novel sensor with corresponding filter electronics was developed at the ISL. Several tests have already proven its usability in the challenging multishot railgun environment.