Employees at the Japan Advanced Institute of Science and Technology (JAIST) have developed the ProTac system, which helps robots simultaneously sense the proximity of objects and physical contact with them. They can now "see" through their hands and understand when they touch objects.
To achieve this, a camera is built directly into the hand and coated with a special polymer that changes its transparency. The system itself consists of a hollow cylinder with a soft shell made of a transparent polymer, topped with a layer of liquid crystal material (PDLC).
When voltage is applied, the PDLC becomes transparent, allowing two cameras inside to capture the surrounding space. When an object approaches, the robot can stop or move away to avoid a collision. In opaque mode, the cameras only see special markings on the inner surface.
When the outer shell is touched, the distance between the markings changes, allowing the system to accurately determine the location and force of the touch. This allows the robot to receive feedback about the physical interaction. ProTac also has a "blinking mode."
The polymer rapidly switches between transparent and opaque states, enabling the system to simultaneously track a person's movements and register touch. According to the developers, this technology could be used in robots to safely interact with people or accurately grasp objects without damage.
