Robot hands are commonplace, but their sense of touch is crude compared to that of a human. A design proposed by a group of scientists in the Middle Kingdom may change that.
A team at the University of Science and Technology of China have developed a bioinspired soft finger (BSF) that uses sensors to give bots the ability to detect precise changes in pressure, and to move with a dexterity comparable to that of a human finger. In a paper [PDF] published in the journal Cell, the team envisages that bots could use their newfound sense to measure humans’ pulses, check for lumps, or politely conduct other intimate examinations without causing patients the embarrassment of dealing with a human doctor.
“We believe that a dexterous hand made of such fingers can act as a ‘Robodoctor’ in a future hospital, like a physician,” explained Hongbo Wang, author of the study and a sensing technologies researcher.
“Combined with machine learning, automatic robotic examination and diagnosis can be achieved, particularly beneficial for these undeveloped areas where there is a serious shortage in health workers.”
The robot doctor will see you now – Click to enlarge. Source: Yufeng Wang.
The 129mm finger uses air-controlled actuators built into a soft, flexible, photopolymer resin framework, with two conductive fiber coils built in. The first coil controls the finger’s movements and the second is in the tip, connected to a highly sensitive pressure sensor.
In tests, the finger was able to identify artificial lumps built into a sheet of silicone, and take a human pulse by finding the artery on a test subject and accurately reading a heart rate.
“Like our human fingers, the BSF can perceive its own shape and fingertip force in real time (a response time of 50ms for both actuation and bending sensing), with a high sensing resolution of 0.02 for the bending angle and 0.4 mN for the force,” the paper states.
“The bending and force sensing of the proposed BSF is self-decoupled and highly repeatable. Crucially, both the sensing and actuation of BSF are robust and mechanically durable for practical applications.”
The idea is that the device could be used by patients who are uncomfortable with having a human doctor – particularly one of the opposite sex – performing an examination. It could also be used in the home to avoid seeing a doctor altogether for precautionary checkups.
The creators also showed off the finger’s ability to type correctly, by judging the force required for key strokes. By using machine learning for control it may also be able to build a robotic hand that could match humans in sensitivity and usefulness.
“By further utilizing accurate sensing data and applying machine learning-based sensing data-driven control in BSF-based bioinspired hands, human-like ‘touch, feel, try, learn, manipulate’ and sophisticated human-robotic interactions can be realized,” they conclude. ®
