Live data from Hacker News

Wireless system can power devices inside the body

news.mit.edu

31–40 of 42 posts

Re: Wireless system can power devices inside the body

#31
post #17

>The implants are powered by radio frequency waves, which can safely pass through human tissues. In tests in animals why animals? couldn't the researchers just swallow that "prototype about the size of a grain of rice" themselves and/or get several paid volunteers?

Because if it turned out to be dangerous it has been determined that the animals being hurt/killed is better than that happening to human test subjects.

Re: Wireless system can power devices inside the body

#32
post #17

>The implants are powered by radio frequency waves, which can safely pass through human tissues. In tests in animals why animals? couldn't the researchers just swallow that "prototype about the size of a grain of rice" themselves and/or get several paid volunteers?

Contrary to the other answers to this question, I suspect the real reason is that the prototype is expensive, and way easier to recover from a lab animal’s poo than the researcher’s.

Re: Wireless system can power devices inside the body

#33
post #27

The main thing I got from the MIT article is this: "This system relies on an array of antennas that emit radio waves of slightly different frequencies. As the radio waves travel, they overlap and combine in different ways." This is known as constructive interference, pretty nifty to see it used in this context. The range has been increased from 10 cm to 1 meter since the paper I co-authored on this subject. Impressiv…

Isn't this description flawed though? Waves of different frequencies are independent in power. Thus they don't interfere (when time-averaged) -- at all. Zero. (this is because signals of different frequencies are orthogonal in the time-average integral of product sense)

What creates interference is difference is phase among waves of the exact same frequency.

It's odd that the paper author is making such basic EM theory mistake, and I wonder what the actual device construction is like. (since it cannot work the way he describes at steady state)

Maybe he's interpreting phase modulation as frequency modulation? Of course at steady state all frequencies would be the same, making this a weird/incorrect interpretation I think.

Re: Wireless system can power devices inside the body

#34
Radio waves are used to power cochlear implants. There is a chip & receiver unit that is inserted under the skin on the head, with electrodes that go into the cochlea. Externally there is an antenna that is held on the head next to the skin, using a magnet to hold it in place. Radio waves are sent across the skin to power the chip and control the electrodes.

Re: Wireless system can power devices inside the body

#35

Plenty of nefarious applications for this. The range alone blows away existing RFID designs, which will make it the preferred "chipping" technology for surveillance states everywhere.

Right now the preferred "chipping" technology is your smart phone.

Re: Wireless system can power devices inside the body

#36

Plenty of nefarious applications for this. The range alone blows away existing RFID designs, which will make it the preferred "chipping" technology for surveillance states everywhere.

Right now the preferred "chipping" technology is your smart phone.

As bad as smartphones might be, I hope you're not seriously trivializing actual implants by comparing them to smartphones.

You can leave your smartphone at home.

Re: Wireless system can power devices inside the body

#37
post #36

Earlier quoted context omitted.

Right now the preferred "chipping" technology is your smart phone.

As bad as smartphones might be, I hope you're not seriously trivializing actual implants by comparing them to smartphones. You can leave your smartphone at home.

The analogy is, retrospectively, not the best. I was alluding to the fact that most people take them almost everywhere they go, which is good enough for a surveillance state.

Re: Wireless system can power devices inside the body

#38
post #7

How much energy could a device extract from blood sugar?

I'm waiting for someone to invent the implantable chip that converts blood sugar into heat/light purely with the intention of wasting that energy. Grab enough power to monitor blood sugar, to make sure you aren't putting someone into a coma, but otherwise just try to burn an extra few hundred calories a day.

You're thinking too fancy - with our technology today, we could install a bypass valve at the pyloric sphincter that just dumps chyme into a stoma appliance/bag.

Re: Wireless system can power devices inside the body

#39

Earlier quoted context omitted.

Then you need to radiate heat somewhere. If you heat up the blood the body will spend less energy keeping warm leading to no benefit. If you generate a lot of heat... it goes really bad.

Easy, simply install a venting port in the patient.

The first patient should be a congressman then, because they already have a hole they blow hot air out of.
Post reply on HN