The fact that straight razors are common implements of torture and murder in horror movies is proof enough that they’re innately terrifying. Anyone who has ever had the pleasure of being shaved with a straight razor knows that they’re scary enough in the hands of a skilled and benevolent barber. One slip of the wrist and boom, you’re missing a face. But that experience pales in comparison to letting a robot get anywhere near you with a straight razor. Roboticist John Peter Whitney risked his own life to let his straight razor-equipped robot do exactly that.
To alleviate your empathetic anxiety, we should point out that this robot is not autonomous. That means a bearded subject isn’t trusting their life entirely to a robot’s whims. Instead, it operates much like a surgery robot. An operator is in complete control of the blade at all times and the robot is incapable of acting on its own — unless something goes horribly wrong. In this case, the operator is a professional barber named Jesse Cabbage from Somerville, Massachusetts’ Dentes Barbershop. The key to the shave going unsuccessfully and not resulting in a bloody travesty is high-fidelity feedback, and that capability is what makes Whitney’s robot special.
Whitney had previously developed a unique fluidic actuator system, which is sort of like teleoperated hydraulic transmission. It’s similar to an old school pantograph machine, but with far more complex capability. The operator moves a control input that mimics the end effector, which pushes fluid through tubes to actuators on the end effector that match those on the input. The setup is ideal, because forces can be pushed back through the tubes to the operator’s hand. In this case, that means the barber can feel the straight razor pushing against Whitney’s face just like if he were touching it directly. The goal here isn’t to introduce a convoluted new shaving system, but to demonstrate how these fluidic actuators can be used for delicate work that requires very sensitive force feedback.