Digital-speech enhancement can now increase the intensity and audibility of some segments of human speech. Research projects are underway to reduce the size and cost of hearing aids, improve their directional capabilities, and identify and amplify desired sounds such as a human voice while muting background noise.
Electronic-skin prototypes are stretchy, thin films that can sense temperature, pressure and even monitor blood oxygen or alcohol levels. But most of these devices are missing hair—a key feature of real skin that allows us to feel a wider range of conditions.
Now researchers have combined hair-like wires with electronic skin to make a more versatile sensor for robots, prosthetics and other applications. Robots and prosthetics are becoming ever more human-like, but the electronic skins designed to enhance their usefulness don’t yet have the full range of tactile senses that we have. To capture that sensation, some researchers have developed separate sensors that mimic the fine hair by sensing and detecting air flow.
Looking ahead
Thanks to significant advances in microfluidics and electronics, e-nose and e-tongue technologies will evolve both in terms of robustness and reduction in the current needed to optimise each application—a process that requires significant investment of time and resources. Miniaturisation will further extend flexibility.
Beyond food, e-sense technology may find applications in environmental analysis to detect water contamination or illicit drugs; in clinical diagnostics to monitor saliva, sweat or urine; and in agriculture to detect fungal contamination in feed. However, both e-nose and e-tongue technologies need improvements in sampling procedures (by reducing clean-up or extraction before analysis, for example) and reduction of carry-over/environmental noise (for instance, in the form of moisture contamination), which affect sensor drift and sensitivity.
