You can see it in action [here on Youtube](https://youtu.be/_FDZzKAFSz4), and all the .stl files can be downloaded [here on Thingiverse](https://www.thingiverse.com/thing:3737144). Can be powered by a balloon, or just by blowing air into it. Used in this [little toy car](https://skfb.ly/6LV6D).
![](https://i.imgur.com/JHsGiUt.jpg)
![](https://i.imgur.com/iaMC1VM.jpg)
Just a few of extra parts needed for the assembly:
* 3x nitrile glove fingers (blue part)
* 15x M3x8 bolts
* 2x M3x12 (or longer) bolts
* 17x M3 nuts