This Robot Knows How to Pick ‘Em

A small, yet dedicated, subset of the hardware hacking community likes to hone their problem-solving skills by gaining a deep understanding of locks and their mechanisms. After studying different types of locks and how they work, they gradually move on to practice using specialized tools like picks and tension wrenches to unlock them. As hobbyists improve their skills, they can attempt more complex locks and challenges, such as speed-picking or even opening safes. Aside from the educational aspects of the challenge, many enthusiasts also see lock picking as a way to improve security awareness and encourage better lock design.

Once the basic tools and techniques have been mastered, lock picking becomes more of an exercise in patience than anything else. YouTuber Sparks and Code realized this, and thought it might be fun to combine that hobby with robotics to build an automated lock picking system. Called the Lock Pick Robot 2.0, this system has a clever design that does away with the traditional set of tools to make automation of the process much simpler.

If you look inside of a lock, you will find a set of pins that are designed to come into contact with the teeth of a key. These teeth push the pins to precise positions, which aligns them in such a way that the key can be turned, and the lock opened. Traditionally, a pick is used to push these pins up and down manually to search for the right combination that will allow the lock to open.

That would be hard to automate, so Sparks and Code instead designed a 3D-printed keyblade with holes that hardened steel wires can slide through. By pushing or pulling on that wire, the position of the pins inside the lock can be tweaked. And once the correct combination is found, it will open.

This keyblade was attached to a 3D-printed frame with guides for the wires, as well as linear actuators and stepper motors to move them under control of a program. Another stepper motor was included to turn the whole robot to try to unlock the lock. An optical encoder was utilized to determine if the lock was actually spinning or not. Without this, the motor would apply too much pressure and snap the plastic keyblade frequently.

There were many problems that came up along the way, largely due to factors like plastic fatigue and friction, that made this a very slow and frustrating build to complete. But in the end, Sparks and Code was successful and the robot proved that it could pick a lock, albeit very slowly.

The software simply runs through every possible pin state in a brute force attempt to open the lock. That amounts to as many as 100,000 attempts, and given the speed at which the robot can move, that would take about six days of non-stop operation.

While this is quite an interesting build, it is not entirely practical for real-world use. It requires a very long time to work, and given the relative fragility of the 3D-printed parts, it is very likely to break before ever finding a solution. It is still definitely worth watching Sparks and Code build the robot, but if you lock yourself out of your house, and are so inclined, you would be better off using traditional tools to open the lock.