
3-D printed plastic objects that can communicate with WiFi devices - soofy
http://www.washington.edu/news/2017/12/05/in-first-3-d-printed-objects-connect-to-wifi-without-electronics/
======
gipp
> Imagine a bottle of laundry detergent that can sense when you’re running low
> on soap — and automatically connect to the internet to place an order for
> more.

Why. Why why why do all IoT-related articles always use awful consumer goods
examples like this. Nobody, or next-to-nobody, would want to have that. There
are so many good ideas and existing uses of IoT tech outside of the consumer
goods sector, and pretty much every application _in_ the consumer goods sector
is hot garbage, and consumers know it.

~~~
sweezyjeezy
> There are so many good ideas and existing uses of IoT tech

Could you give some examples? I've yet to hear a single IoT thing I'd be
willing to pay money for.

~~~
majewsky
Just yesterday, it occurred to me that an IoT thermostat would be nice ( _if
and only if_ it doesn't mean that a server failure results in me freezing).
Right now, I have the choice of heating the house all day (thus wasting heat =
energy = money while I'm not home), or coming back to a cold house, turning up
the thermostat and then having to wait 1-2 hours until the room is pleasantly
warm. (My apartment is understaffed in the heater department and I cannot
change that easily since I'm renting.)

~~~
jstanley
It's quite easy and cheap to make a wifi-connected thermostat yourself. I did
it, it's great.

I made a web interface so that I can control it with my phone when I'm not at
home.

It is based off an ESP8266 placed in the boiler which controls a relay to tell
the boiler whether to heat or not, and an ESP8266 in my office that has a
temperature probe and a rudimentary user interface, and runs a web server to
allow remote temperature inputs, and controls the ESP8266-relay over WiFi.

The 3d-printed enclosure is rather coarse, but does the job:
[https://img.jes.xxx/1585](https://img.jes.xxx/1585)

EDIT: Failure of the system could result in you freezing, but that's true of
anything that controls your heating, and at least this is a device you
understand are in control of, and it doesn't rely on anything outside your
house. If it fails and you're freezing, just short the terminals of the relay
while you debug it.

~~~
GistNoesis
If you are in Europe, you can also buy the ESP8266 from Olimex with relay, box
and eventual lipo plug. You then just have to flash your code on it. Only
downside is they are not properly shielded electromagnetically so they can
only be sold as Kit for experienced users (as certification costs would
dominate the price). Also, if your house happens to burn, you can be pretty
sure the insurance companies will pin it on your uncertified DIY appliances.

~~~
TeMPOraL
> _Also, if your house happens to burn, you can be pretty sure the insurance
> companies will pin it on your uncertified DIY appliances._

This is one thing that's constantly on my mind when toying with long-lived
electronics projects. Do we know of an actual precedent here?

~~~
GistNoesis
I don't know of actual precedent, but there are numerous examples of lipo
house fires (which aren't fully covered). And semi related personal one-
datapoint anecdote I've experienced water damage and robberies in the past and
they were a lot more prompt to try to find loopholes to not have to pay. I
can't afford to set a precedent, so I stick to fused low voltage off the shelf
products.

------
teilo
"connect to WiFi" is not remotely accurate. It should be: "Reflect wifi
signals in a predictable pattern." This technique, while impressive, requires
custom hardware/software to detect and interpret (presumably via filtering and
a fourier transform) the back-scatter signal.

~~~
comboy
Yup, only plastic is also misleading since they need some conductive antenna.
It's still very interesting and impressive, but somebody please fix the title.

~~~
teilo
This is really just a form of passive radar. It's using ambient signals
instead of an active beam, but the analysis techniques used are essentially
equivalent. It's like stealth technology in reverse. You are intentionally
creating a recognizable radar signature.

~~~
jackhack
All this to replace a slip of paper (aka "shopping list"). We have gone
barking mad.

~~~
JoeAltmaier
Ha, your cell phone is sort of like that. All that to replace, just waiting
until you get home to make the call.

To be fair, this 3D trick also replaces remembering, driving, buying,
restocking.

~~~
icebraining
_driving, buying, restocking_

How so? You can already order online. All this devices replaces is the clicks
it takes to do that.

A cellphone means you don't have to choose between receiving calls or going
out. It's incomparable in its utility.

------
wonderous
Anyone that finds this interest should look at how “The Thing” (1945) worked:
[https://en.wikipedia.org/wiki/The_Thing_(listening_device)](https://en.wikipedia.org/wiki/The_Thing_\(listening_device\))

EDIT: Here are some diagrams of how it works:

[https://hackaday.com/2015/12/08/theremins-
bug/](https://hackaday.com/2015/12/08/theremins-bug/)

~~~
malikNF
You should submit this as a HN link, really interesting story. Thanks.

~~~
Tempest1981
2 months ago:
[https://news.ycombinator.com/item?id=15498685](https://news.ycombinator.com/item?id=15498685)

11 previous submissions:
[https://hn.algolia.com/?query=listening%20thing&sort=byPopul...](https://hn.algolia.com/?query=listening%20thing&sort=byPopularity)

5 more:
[https://hn.algolia.com/?query=theremin%20soviet](https://hn.algolia.com/?query=theremin%20soviet)

------
worldsayshi
This is a truly awesome technology. But ITT an abundance of nit-pickiness on
how this isn't _exactly_ what the title says it is or how it could be
presented better.

Yes, the nitpicks are correct. But wouldn't it be more inspiring to talk about
how it could be used?

~~~
btbuildem
It's not that awesome. Miniature, WIFI-capable components with batteries that
would last years already cost very, very little. This is a strange use of a
low-tech approach, seems to fall under the "We can, but why would we?"
category.

------
iamnotlarry
"Without electronics" except for the computer devices that have to be
dedicated to monitoring for the back-scatter created by the 3-D printed
objects and translate it into something meaningful.

~~~
worldsayshi
"Dedicated"? Can't the devices that is already nearby, like a router or your
smartphone, query it when needed?

~~~
whichfawkes
They can't query it, they have to be listening when it broadcasts.

~~~
worldsayshi
Yeah ok I understand that it doesn't have a memory. But you can still sort of
"query" the current state of a device that is always broadcasting, like a flow
or speed sensor.

------
vog
This is a surprisingly simple solution to the problem: Make the working
"device" (3D printed object) do as little work as possible - just enough to be
detectable by the surrounding devices that are "real" computers anyway.

~~~
Cthulhu_
It's a bit like it sending out an audio signal (which would be another option
I think) that can be interpreted by a receiver.

~~~
jpindar
This has been done - there are modules that detect and decode audio (which
sounds a bit like R2D2). The manufacturer provides clips of this audio, which
you could play from an app, allowing a phone to control something without it
having to be on a network.

Unfortunately, AFAIK the technology doesn't have a searchable name, so I can't
find anything about it now.

Of course, being able to listen for an arbitrary audio signal would be even
more useful.

~~~
TeMPOraL
Here's a stupid idea I have (I'm pretty sure it's patented 'till kingdom come,
but if not, then this is prior art and I want this to be public domain):

    
    
      (side view)
    
            +-------------+          
        +---+  BUTTON     +--------------------------------+
        |   |             |                                |
        |   +-------------+                                |
       -+ <-- valve                                        |
        |  +--------  -------------------------------------+
        |  |           flute          x x x x x x x x x x        <-- sounds comes
        |  +-----------------------------------------------+         out here
        +--------------------------------------------------+
    
                                      x - a hole with an externally accessible
                                          lever that can be used to open or close it
                                          

Basically, you press the button, which pushes air through a flute, thus making
a sound. The sound is configurable through pluggable holes (marked with x). In
the diagram above there are 10 of them, giving you 1024 possible sound
frequency combinations to listen for with your central IoT device.

Pros:

\- No electricity needed.

\- Fully configurable, open source.

\- 3D-printable maybe? Still, can be entirely plastic, so even more dirt-cheap
to manufacture than the backscatter thingie.

\- Less chance of interference - it's easier to keep the sound contained
within your apartment than it is to keep radio waves.

~~~
logfromblammo
That's not quite how flutes work. Two open tone holes in the same air column
do not produce two distinct tones. They combine to change the effective length
of the air column, which then provides a resonance for one tone, the frequency
of which is determined by the length and the speed of sound, which in turn is
mostly determined by temperature, and partly by the humidity. You still need a
reed to produce the initial vibration.

I think what you are aiming for is more on the order of a disk siren. The
rotation speed could be adjusted to produce a different base frequency, and
one siren disk can support tone production from several air streams, each
aimed at a different radius of the disk. Blocking off or opening the
individual air streams can produce different chords based on the base tone.

If you have twelve speeds and six air streams, you can make 767 different
chords. The same rotor can turn the siren disk and a fan to move the air. You
press the button, the disk spins, and a pre-programmed chord plays.

~~~
TeMPOraL
Thanks for clarification. I never thought hard about how flutes work.

Still, based on your explanation, I feel that a fully-mechanical device that
has hundreds of configurable tones and is operated through pressing a button
should be feasible for easy mass-production and/or even 3D-printing.

------
JepZ
Actually, I wonder how much those devices would interfere with the normal
wifi, like "when the wind starts to move at higher speeds, my movie stops
playing" ;-)

------
bsimpson
It's a clever idea, but without a 1:1 connection between an object and a
network, it seems too dumb to be useful.

How is my WiFi network supposed to know that the interference in the signal
came from my detergent bottle - not my neighbor's, and not from some other
random object passing by? Do I have to do some sort of pairing every time I
buy a new detergent brand to teach my network about it?

~~~
jrowley
If pairing became an issue, amazon could associate a new bottle with your
account before they ship it to you, and automagically register the device with
your router. As an added bonus you could get a real confirmation that the box
arrived when it is delivered.

This is a really interesting idea for IOT. I'm really excited by the
possibilities it could open up.

------
nvahalik
Curious to see the impact this would have on wifi performance. Wouldn't this
cause all of the really fun stuff making WiFi fast (beamforming, channel
hopping, etc.) a lot less effective? Would be curious to see more information.

I imagine this would be really good for things like weather sensors or even
security systems... but I have serious doubts of the efficacy of what they are
doing.

------
lakechfoma
Interesting tech but the consumer products example is broken to me because I
don't want to be throwing out even more plastic.

~~~
TeMPOraL
It's a potential alternative to some IoT ideas, which have you wasting
plastics _and_ metals _and_ powerful microcontrollers just to transmit a
button press...

------
bpowah
So my WiFi should easily be able to detect if my (all metal) garage door is
open or closed? I would like this. I run dd-wrt. Is there an all-software
solution to this? Or does this research rely on fairly specialized hardware?
(sorry, didn't have time to read the whole article)

~~~
icebraining
It requires a custom 3D-printed "device" on the door, which would modulate the
Wi-Fi waves being scattered around (by your router, laptop, etc) into a signal
that would indicate "open" or "closed".

~~~
helb
I think the point was that the large moving metal object (garage door) itself
would mess with the signal enough to detect the state without any additional
device…

~~~
detaro
I guess a first good experimental step would be to point a directional Wifi
antenna in the direction of the door and monitor what it receives at what
strength.

------
k__
While rather impressive it sounds like a huge security problem to me.

With machine learning someone could probably train models that know what you
are doing in your home.

~~~
sitkack
Look at the other 3d sensing systems using Wifi by the University of
Washington. It already is possible to form 3d pictures using microwave
backscatter from ambient emissions.

------
quirkot
Imagine 50 years from now inheriting a vase from your deceased relative that
has been an undetected malware portal for decades! How exciting!

~~~
icebraining
How can you hack something without software, electronics, and memory?

~~~
jhiska
Since you worded that as a challenge... by maliciously modifying the CAD files
that will be fed to the 3D printer.

...or by building an otherwise identical object that manipulates flaws in how
the Wi-fi reads the signals and then replacing the original object with the
malicious one.

------
sitkack
I am reminded of
[https://en.wikipedia.org/wiki/The_Thing_(listening_device)](https://en.wikipedia.org/wiki/The_Thing_\(listening_device\))

This development will probably lead to a new combination of something like
RFID, WiFi and electromagnetic power delivery (AM radio).

------
XnoiVeX
Ignore the soap example and just focus on the underlying Wi-Fi backscatter
technology. There are many applications in extreme low power or no power
devices. Most are missing the point.

More details here.
[http://iotwifi.cs.washington.edu/](http://iotwifi.cs.washington.edu/)

------
baybal2
So what it is: mechanically modulated, very low frequency, passive microwave
transmitter. No wifi anywhere there

------
jbb67
How can this _possibly_ work? You can't make a connection to Wifi or implement
any of the protocols that run over by passively reflecting some signals. All
of them require some processing and two way communication. The article just
makes no sense at all. It is 1st April?

~~~
justusthane
It's explained in the article, although the title is inaccurate. The 3D
printed devices do not, themselves, connect to WiFi. The backscatter is picked
up by a WiFi receiver which is connected to the WiFi. But if you're going to
comment, why not take the time to understand the article instead?

~~~
jbb67
I read and understood the article fully thank you. Wifi does not work like
that and this cannot possibly work.

~~~
teraflop
"this cannot possibly work" \-- are you claiming that the working prototype
depicted in the video is a fraud? That's a very serious allegation.

------
tinus_hn
Cool idea, I'd like to see how much distortion this causes on the Wifi
channels though. They are already overflowing.

------
ogre_magi
As landfills pile up with wifi-reflecting garbage we will truly be realizing
the dream of the IoS (Internet of Shit).

------
chrischen
I’d imagine with conductive filament and a cheap microprocessor or bluetooth
radio you can so the same or much more.

~~~
JoeAltmaier
Its called an RFID tag

~~~
libertyEQ
Which we technically call transponders, and while they do have EEPROM, they
don't normally have CPUs.

------
emilfihlman
>In first, 3-D printed objects connect to WiFi without electronics

No.

------
archibaldJ
Aww I remembered seeing this being presented in Siggraph Asia this year. Cool
to see it popping up on HN now!

------
hathym
over-engineered stuff that does not really connect to anything! but needs a
special device to permanently listen to signals from the 3d printed toy.

------
zzzeek
so, malware on my phone can fake these signals and order 200 gallons of
laundry detergent for me?

~~~
JoeAltmaier
Not sure at all how that would work. Can your phone generate arbitrary
backscatter waveforms? I don't think it can.

~~~
TeMPOraL
If the malware could access and modify the radio driver then why not? Also,
TX-capable SDRs are getting cheaper and cheaper :).

~~~
JoeAltmaier
Radios are largely hardware in the TX component. Not a lot you can do but
point them at data. I'm not sure ANY data pattern looks like backscatter?

------
Vektorweg
Zero security though.

------
baybal2
Deceptive headline, please rename

You renamed it, but it is still does not indicate that the thing does 0 actual
wifi protocol communication.

