Gravity Catapult

I have long been enamored of catapults. Invented around 400 B.C., they were used until nearly A.D. 1300. So for 1,700 years, catapults were arguably the largest, most expensive, and most powerful machines on the planet. Today, people build catapults for fun: Scout troops, historical reenactors, fathers and daughters, beer-stoked... Read more »

One-Ton Linear Servo

RC hobby servomotors were just made for hacking. What’s not obvious is how much you can hack them — with a few tricks, you can use a servo to control almost anything. Hobby servos consist of a DC gear motor, a potentiometer (usually 5K), and a control circuit. The output... Read more »

Portrait Window

This is a project that celebrates friends. The core group. The people you can count on for a ride to the airport at 6:30 in the morning, or to help you drag a new sofa up three flights of stairs. The people who allowed themselves to be seen with you... Read more »