First of all, I don't necessarily recommend that you attempt to duplicate this project, but how I made this contraption is in the video above.
The important elements are:
- Nitinol wire - to get hot enough to ignite fuse
- Lever Nuts - hold the Nitinol wire in place. Really impressed with these as they hold very securely and can work with 12-28 AWG wire.
- 3D Printed frame to hold the electronics and fit in between the 'beests legs
Here is the Arduino and 3D printing files that I used.
Neither is optimized, so use at your own discretion.
Printed on a Monoprice Maker Select mini V2.
*Note that Amazon links on this writeup are affiliate and that the Arduino Nanos linked may not be from the same manufacturer as used here.