https://www.computerworld.com/article/2473016/computer-hardware/90160-tk.html#slide2
This was done by using a xbox 360 Kinect a pair of Mac books and two projectors to track the kids and use the shadow to then projects the image of the silhouette on the wall
I think that only one person worked on this project.
This project would have taken a week to set up with only one person because of the lack of imported items to make it work