article_snippet.sent: When a plane - which currently only takes place a few times a year is parked and empty, the device, which is the size of a drinks cart, patrols the aisles using motion sensors to navigate a plane - which currently only takes place a few times a year.
article_snippet.sent: When poor plane is parked and empty, the device, which is the size of a drinks cart, patrols the aisles using motion sensors to navigate poor plane.