To most people, a knife-wielding robot probably sounds a bit scary. But some fearless researchers at the Institute of Robotics and Mechatronics at the German Aerospace Center (DLR) have armed a robot with various stabbing and slicing instruments, and have programmed it to restrain itself from injuring people.

The team equipped their robotic arm with scissors, kitchen knives, a screwdriver and a scalpel and had it stab and slice different materials, including a piece of silicone and a pig’s leg, at varying speeds. The group then implemented a detection system that uses force sensors on to detect when the robot has accidentally cut something. In the stabbing motion, the safety program resulted in much smaller cuts (as little as 1mm); for the slicing motion, it prevented the robot from cutting the pig’s leg entirely.

The researchers demonstrate the effectiveness of the safety system on a (very trusting) human volunteer at the end of this video.

The group presented the work at the International Conference on Robotics and Automation (ICRA 2010) this week; last year the team demoed a system designed to prevent robots knocking over crash test dummies.