橡皮筋動力車

1

https://www.youtube.com/watch?v=jHHt5K4TpFM

https://www.youtube.com/watch?v=q7s58Vhdl4g

2

https://www.youtube.com/watch?v=exuXoln101s

https://www.youtube.com/watch?v=6he62a1uiRs

3

https://www.youtube.com/watch?v=VmCMpDT6-Q8