A spring loaded device that is activated by remote then use another chanel and a strong servo to reset?
Seems to me you need to do something more involved than bolting on a strong springy antenna for tje grade.
Need to show innovation and research....
Now if you experimented with a number of different materials, develop a way to make a metal into a springy "antenna"....etc......that may please your proffessor.....
Your grade will be largely on your process of innovation....application of scientific method and research experimentation.....