This week’s selection is the Supersonic Trebuchet by YouTuber Tom Stanton.
Stanton is an aerospace engineer who’s been building trebuchets since the age of twelve. This project is the culmination of all that expertise, and attempts to fire a projectile faster than the speed of sound — 1250 kph.
In the video, we’re taken through Stanton’s development process, which makes extensive use of 3D printing, as well as CNC milling. Note the safety steps he takes when cutting dangerous carbon fibre.
The trebuchet design is quite unusual. Normally, a trebuchet simply tips like a see-saw and flips a projectile forward. However, in order to achieve the incredible speeds on this project, Stanton used a couple of interesting approaches:
A gravity design that pulls a weight downward for energy
A hub that spins faster and faster and eventually releases the projectile
Stanton gradually optimizes the design through a series of iterations, making things more aerodynamic, lowering weight, adjusting torque, etc. Each step improved performance and often required 3D printing to replace part designs.
Ultimately, the rotation of the hub was an amazing 2342 rpm, achieved in only a second or two. This was enough to propel the projectile — a 4g 3D printed sphere — at just over the speed of sound. In the video, you can actually hear the sonic boom from this tiny object as it is released from the trebuchet.
The moral of the story here is that 3D printing enables almost anyone to explore ideas and designs. Stanton himself says:
“With the accessibility to modern engineering tools like computer-aided design software, a homemade CNC milling machine that can cut metals and carbon fibre, and the endless possibilities of 3D printing, the supersonic trebuchet has now become a reality.”
Via YouTube
