A team led by David Franklin, Professor of Neuromuscular Diagnostics at TUM, has teamed up with the University of Tokyo. Here, scientists led by Prof. Takao Someya have developed a so-called nanomesh sensor. It consists of four ultra-thin, nanostructured layers that are perfect for measuring the human sense of touch.
A layer of polyurethane nanofibers serves as a passivation and carrier layer. This is followed by an ultra-thin layer of gold, an intermediate layer of parylene-coated polyurethane nanofibers and finally another layer of gold. A final thin layer of polyurethane and polyvinyl alcohol nanofibers mechanically protects the four layers of the sensor.
The nanomesh layers are produced using an electrospinning process. The polyurethane nanofibers are between 200 and 400 nanometers thin, two hundred times thinner than a human hair.
The gold layers are a type of line matrix that forms the functional electronic component of the sensor. To produce them, gold was applied to a carrier layer of polyvinyl alcohol, a plastic that is also used for contact lenses. This is rinsed out after the layer is produced so that only the gold fibers remain.
One area in which the sensor could be used is the digital archiving of crafts. The fine motor skills of a watchmaker could be precisely documented with the help of the Nanomesh sensor on his fingers.
In fact, it is the world's first finger sensor that can take measurements without the loss of human sensitivity. And despite its thin nature, the sensor is very stable: in abrasion tests with a pressure of one kilogram per square centimeter, which roughly corresponds to atmospheric pressure, its capabilities were not lost even after 300 repetitions. "This shows that we can measure the manipulation of any kind of object - this was not possible before."
Source: TUM
Publications:
Sunghoon Lee, Sae Franklin, Faezeh Arab Hassani, Tomoyuki Yokota, Md Osman Goni Nayeem, Yan Wang, Raz Leib, Gordon Cheng, David W. Franklin, Takao Someya: Nanomesh pressure sensor for monitoring finger manipulation without sensory interference. Science, DOI: 10.1126/science.abc9735
