The Future is Here: Sweat-Powered Smart Tatoo

smart_tatoosSmart tattoos are the hot ticket item of modern medicine, combining ultra-thin electronics with flexible materials. When they become commonplace, they will be a great way to monitor vital signs and health. The only thing that seems to be holding them back, is finding a way to power them. Tiny batteries are one possibility, but lack practicality, and microwaves are several years away from being feasible.

Luckily, Joseph Wang – a researchers from UCSD – has come up with a way to generate power for these devices without using any external equipment. The secret, is to harness electrons from lactate acid secreted in sweat. These acids are produced when our muscles work to exhaustion, a waste product that causes muscles to “burn”, but which the brain thrives upon. Hence why it is the endpoint in lactate’s metabolization cycle. lactate was discovered to be released in sweat, exercise physiologists began developing sensor technology to measure its levels in the sweat and blood. Wang has taken the next logical step of adding provisions to accumulate charge when lactate is enzymatically sensed. By embedding enzymes that process lactate into the tattoo, he was able to extract 70 microwatts per cm² of skin.

The only catch with this tattoo is that you need to be hot – as in pedaling your heart out on a bike for 30 minutes – to get the lactate out. That, however, may not be a barrier to this technology, since it is possible to selectively activate the sympathetic nerves that control the sweat glands in a discrete patch of skin. That way, you override the normal control and can sweat without the heat or exertion.

flexible_elecThe other part of the puzzle would be to actually generate the lactic acid. Preferably, this would be done locally as well, rather than having to have high levels circulating in the blood. But in the end, such steps would not even be necessary considering that a vitals and health monitoring that occurs into a workout – after an initial warm-up and good sweat have taken place – could be just what the doctor ordered (no pun intended!).

Other researchers have already imagined e-tattoos to read your thoughts and desires, either by reading unvocalized words or EEG readings. And compared to past generations of sensor devices, these tattoos represent a sophisticated electronic package with on-board signal processing and communications. With a discrete way to power such devices, a formidable tool for self discovery might be had.


The Future is Here: MMI Electronic Tattoos!

patchIt’s known as Mind-Machine-Interface, the ability to interface and control machines using only your mind. And thanks to a number of dedicated researchers in various fields, it’s no longer the stuff of science fiction. With mind-controlled prosthetics, bionic limbs, and the growing field of machine-enabled telepathy, the day may soon come when people can interface, access and control machinery with just a few thoughts.

But of course, that raises all kinds of concerns about invasive procedures, whether surgery will be needed in order to implant devices into the human brain that can translate brainwaves into commands. Alternately, where non-invasive means are involved, it can take some time to calibrate the machinery to respond to the user’s nerve impulses. As those awful infomercials say, “there has be a better way!”

patch_headAs it turns out, electrical engineer Todd Coleman and his team at the University of California at San Diego has been working on a way to use wireless flexible electronics that one can apply on the forehead just like temporary tattoos. Building on the emerging field of biomedical electronics, these tattoos will be able to read brainwaves and allow a person to control electronic devices without the need for surgery or permanent implants.

The devices are less than 100 microns thick, the average diameter of a human hair, and consist of circuitry embedded in a layer or rubbery polyester that allow them to stretch, bend and wrinkle. The devices can detect electrical signals linked with brain waves and incorporate solar cells for power and antennas that allow them to communicate wirelessly or receive energy.

patch_breakdownOf course, other elements can be added as well, like thermal sensors to monitor skin temperature and light detectors to analyze blood oxygen levels, making it both a health monitoring patch and a fully-integrated control device. Combined with health patches that are being developed for use internally, an entire health network can be created that allows for every aspect of a patients health to monitored in real-time, anticipating and predicting health problems before they flare up.

Currently, Coleman and his colleagues are pursuing the application of using these patches to monitor premature babies to detect the onset of seizures that can lead to epilepsy or brain development problems. The devices are also being commercialized for use as consumer, digital health, and medical device. But the potential for their use is staggering, even alarming.

droneFor example, these devices can also be put on other parts of the body, such as the throat. When people think about talking, their throat muscles move even if they do not speak, a phenomenon known as subvocalization. Electronic tattoos placed on the throat could therefore behave as subvocal microphones through which people could communicate silently and wirelessly to each other.

However, a more alarming application is in the industrial and defense field, which is being pursued by the startup MC10 in Cambridge, Mass. In the course of their research, Coleman and his colleagues found that individuals who were hooked up to a computer through large caps studded with electrodes were able to remotely control airplanes and a UAV over cornfields in Illinois. Such is not possible with these tattoos at present, but Coleman admits that he and his colleagues are “working on it”.

telepathyBut even more alarming than this is the long term implications of what this could mean for us as a species, which is that electronics could one-day enable wireless peer-to-peer brain communication – aka. machine-enabled telepathy. With devices that can read and transmit brainwaves and vocal information, it would no longer be necessary for people to use radios, phones, email, or any other means of communication to talk to one another.

Simply tune in, subvocalize or think what you want to convey – and boom! instant messaging and perfected! Lord knows the art of diplomacy might suffer, and we can forget about sarcasm, tact, or shades of meaning. Society may very well breakdown or people will just have to grow thicker skin as everyone is forced to communicate what they really think to each other!