MIT students Grant Jordan and Kyle Vogt found themselves in possession of a high-security safe -- the S&G 8400, a class-1 safe of the sort formerly used to store classified documents. They wanted to open it, but they lacked the combination and were unable to crack it using the sort of techniques that work on lesser strongboxen. So they build a safecracking robot that autodialled combination after combination (the robot excluded "impossible" combinations that couldn't be set due to material limitations of the mechanism, which substantially reduced the keyspace). They eventually opened the safe, but didn't find anything interesting in it.
We used a custom stepper motor to rotate the dialer head. The dialer head transmits torque to the dial via a piece of heavy duty surgical tubing. The stepper motor we chose has more than enough resolution to implement our algorithm, but it's not quite as fast as it could be. Stepper motors have an extremely high "holding torque", which is ideal in this situation since the dial must be held in place while the butterfly knob is being turned.
The head also contains an RC servo motor with a machined knob to mesh with the butterfly knob. This setup enables independent rotation of both the dial and butterfly knob. The stepper motor shaft is also connected to a high resolution optical encoder for position feedback. The encoder is mainly used to detect when safe is successfully opened. The torque required to open the safe when the correct combination is entered is much higher than the maximum torque of the stepper motor, so the encoder is programmed to report when the position error exceeds a certain threshold. Basically, the stepper motor stalls and the encoder flips out if the safe actually opens.
I dote on fidget gadgets — soothing gizmos intended to give your hands something to keep busy with, like modern worry-beads — and while you can’t buy Chris Bathgate’s amazing machined sliders, and the Fidget Cube Kickstarter just closed, there’s still Thinkgeek’s new Jumbo Noah Fidget Toy, which looks like a lot of fun and […]
VPhone is a wee “phone”, surely the most wee of them all. It has a 1.54-inch touchscreen display, Bluetooth, FM radio, pedometer, 128MB (megabytes!) of storage, a heart rate monitor, some social network-monitoring apps, and a choice of “simple and stylish” black or silver trim. The radio’s quad-band GSM, so if you can get your […]
Withdrawn by Samsung and recalled from store shelves, the explosion-prone Galaxy Note 7 is now forbidden in the skies. The Federal Aviation Administration has officially banned it, via an emergency prohibition order, making it a federal crime to take one on board an airplane. The order restricts passengers from carrying the phone “on their person, […]
From self-driving cars to stock market predicting software to the recommendations you get on Amazon and Netflix, machine learning is at the core of modern technology. You could find yourself building technology that is literally changing the world with the skills you’ll learn in The Complete Machine Learning Bundle. This bundle of 10 courses includes 406 lessons that will teach […]
This Python Mega Course will help you learn to code by teaching you to build 10 real-world apps that each highlight a unique use of Python.Job prospects for coders are still growing steadily—and with Python being one of the most popular coding languages out there today, it’s important for job seekers to demonstrate a widespread understanding of the […]
The Atmos R2 may be bigger than the brand’s previously-released vapes, but we argue that in this case it’s definitely a good thing. A bigger heating chamber means more room for packing it full. And the bigger battery means longer, more fulfilling vape sessions. In fact, you can use the Atmos R2 for up to about 25 […]