October 25, 2011 22:04
Example of the new skin has a grating electrode dimensions 8 x 8 and is therefore able to build a picture of the pressure distribution with a resolution of 64 pixels. However, in the long term the packing density of contacts can be lifted (photo Steve Fyffe / Stanford News Service).
Unusual sensor can be stretched to more than twice its original length in any direction. After the load is removed it returns to its original state without wrinkles or damage, do not lose the ability to feel touch.
Prospective cover for arms and torso robot created by Professor Bao Chzhenan (Zhenan Bao) and her team from Stanford, we know to decompose in the body electronics and electronic skin for the first time felt the touch of a butterfly.
The current development of Bao not as sensitive as the previous model, but it is not only able to bend, and stretch. However, it is also clear.
Comprising a new skin for robots of three polymer layers (variations used silicone). The outer two layers — a little harder (of polydimethylsiloxane), medium — softer (polymer Ecoflex). This sandwich can accumulate electrical charges, the amount of stored charge depends on the degree of deformation of the middle layer.
In addition to the obvious first line of new items — skin for robots — a transparent sensor can be used to create a touch-sensitive screens or, for example, medical bandages that can warn doctors about the excessive compression of the affected area (photo Bao Group)
Continuously measuring the properties of such a flexible capacitor, electronics and estimates by clicking to some point.
According to EurekAlert!, The key to the new skin was two layer is very thin and flexible electrodes placed between a pair of outer and inner layers of polymers. These electrodes form a measuring grid.
Electrodes with the desired properties, scientists contrived of single-walled carbon nanotubes, the nanotubes made emerge in the form of tiny springs. They are able to stretch and bend over a wide range without compromising its integrity, and without changing the level of conductivity.
To achieve this, the team sprayed a liquid suspension of nanotubes on a thin layer of silicone, which was then quite stretched sequentially in two perpendicular directions.
Originally located on the surface of the nanotube polymer randomly, creating lumps. But with some of the tension of the film nano lumps stretched along the stretch. And with the release of silicone it back to its original shape makes these elongated aggregates of carbon molecules twist into something like springs.
Subsequently, these springs are already allowed to stretch itself many times without breaking the established form.
No matter stretched "skin" or compressed, the two layers nanotube electrodes closer together. However, the difference between these types of deformation can easily be identified by the pattern of the pressure distribution. Simply put, the painting of the deforming force at different points (photo Steve Fyffe / Stanford News Service).
The creators of the new "skin" argue that by modifying the grid electrodes, can significantly increase the sensitivity of the sensor — to the level of the previous version. That, that felt the butterflies.
But now a new flexible sensor boasts an unusually wide range of measured effort: "From being crushed between the thumb and forefinger to twice the pressure than to develop when an elephant stands on one leg," — said one of the lipoma Darren (Darren Lipomi ).