A color-based sensor to emulate pores and skin’s sensitivity


Robotics researchers have already made nice strides in growing sensors that may understand modifications in place, strain, and temperature — all of that are essential for applied sciences like wearable units and human-robot interfaces. However an indicator of human notion is the flexibility to sense a number of stimuli without delay, and that is one thing that robotics has struggled to attain.

Now, Jamie Paik and colleagues within the Reconfigurable Robotics Lab (RRL) in EPFL’s College of Engineering have developed a sensor that may understand combos of bending, stretching, compression, and temperature modifications, all utilizing a strong system that boils all the way down to a easy idea: shade.

Dubbed ChromoSense, the RRL’s know-how depends on a translucent rubber cylinder containing three sections dyed crimson, inexperienced, and blue. An LED on the high of the gadget sends mild via its core, and modifications within the mild’s path via the colours because the gadget is bent or stretched are picked up by a miniaturized spectral meter on the backside.

“Think about you might be consuming three totally different flavors of slushie via three totally different straws without delay: the proportion of every taste you get modifications when you bend or twist the straws. This is identical precept that ChromoSense makes use of: it perceives modifications in mild touring via the coloured sections because the geometry of these sections deforms,” says Paik.

A thermosensitive part of the gadget additionally permits it to detect temperature modifications, utilizing a particular dye — much like that in color-changing t-shirts or temper rings — that desaturates in shade when it’s heated. The analysis has been printed in Nature Communications and chosen for the Editor’s Highlights web page.

A extra streamlined method to wearables

Paik explains that whereas robotic applied sciences that depend on cameras or a number of sensing components are efficient, they’ll make wearable units heavier and extra cumbersome, along with requiring extra information processing.

“For gentle robots to serve us higher in our every day lives, they want to have the ability to sense what we’re doing,” she says. “Historically, the quickest and most cheap approach to do that has been via vision-based methods, which seize all of our actions after which extract the required information. ChromoSense permits for extra focused, information-dense readings, and the sensor might be simply embedded into totally different supplies for various duties.”

Due to its easy mechanical construction and use of shade over cameras, ChromoSense may probably lend itself to cheap mass manufacturing. Along with assistive applied sciences, corresponding to mobility-aiding exosuits, Paik sees on a regular basis purposes for ChromoSense in athletic gear or clothes, which might be used to provide customers suggestions about their kind and actions.

A power of ChromoSense — its capacity to sense a number of stimuli without delay — can be a weak spot, as decoupling concurrently utilized stimuli remains to be a problem the researchers are engaged on. For the time being, Paik says they’re specializing in bettering the know-how to sense regionally utilized forces, or the precise boundaries of a fabric when it modifications form.

“If ChromoSense positive aspects recognition and many individuals need to use it as a general-purpose robotic sensing answer, then I believe additional rising the knowledge density of the sensor may turn into a extremely attention-grabbing problem,” she says.

Trying forward, Paik additionally plans to experiment with totally different codecs for ChromoSense, which has been prototyped as a cylindrical form and as a part of a wearable gentle exosuit, however may be imagined in a flat kind extra appropriate for the RRL’s signature origami robots.

“With our know-how, something can turn into a sensor so long as mild can go via it,” she summarizes.