Not knowing anything at all about what you are studying, the course requirements, the types of projects done in the past, what you teachers like to see, or even what grade/year you are in, all I can offer are semi-funny random suggestions:
-self balancing two wheel Segway style sex bot -hovering self controlled robotic lawnmower with anti-squirrel features -cornea implantable television so porn can be watched in private -smartphone controlled toilet -small fusion generator -large fusion generator -medium sized fusion generator -not quite small, but not quite medium fusion generator -watermelon moisture tester