In the field of robotics, fingers are one of the most coveted features for robots, along with eyes and brains. Human fingers have an impressive amount of dexterity and sensors that allow them to manipulate complex objects without needing to see them. So developing robotic fingers with human-like abilities can be a breakthrough for robotics outside of factories and warehouses.
In a recent study published at the Robotics: Science and Systems 2023 conference, researchers at Columbia University have successfully trained robotic fingers to deftly manipulate complex objects without dropping them. What is most impressive is that the manipulation is done entirely by touch, without the need for vision.
tactile fingers
The robotic fingers developed by the Columbia University researchers are equipped with a flexible reflective membrane under the skin of each finger, along with an array of LEDs and photodiodes. Each LED turns on and off for a fraction of a millisecond, while photodiodes record how light from each LED reflects off the inner membrane of the finger. When your finger touches something, the pattern of that reflection changes due to the flexing of the membrane. A trained model can correlate that light pattern with the location and width of the finger contacts.
skillful manipulation
Complex objects can be difficult to manipulate even for human fingers, let alone robotic fingers. Columbia University research used reinforcement learning to teach robotic fingers to perform deft manipulation of complex objects without dropping them. This process involved the use of sample-based methods to find trajectories between known states, and then combined with reinforcement learning to develop a trained control policy over the entire state space.
The future of tactile robotics
The Columbia University project is a major step forward in tactile robotics. However, the researchers admit that the exclusive use of touch is an artificial limitation. The addition of visual feedback could further improve the dexterity of robotic fingers and come closer to the ability of the human hand.
Ultimately, the ultimate goal of tactile robotics is to fully replicate the human ability to manipulate complex objects. While Columbia University research has made important strides in this field, there is still a long way to go before robots can match human abilities. Touch robotics has the potential to revolutionize industry, medicine, and many other fields, but only if robots can match or exceed human abilities.
