edit: wifi router could power these sensors, just a limited range.
"we simulate an ASIC, which achieves 60 fps 720p and 1080p HD video streaming for 321 µW and 806 µW, respectively" simulate, how convenient!
"Our inter and intra-frame compression algorithms reduces
total bandwidth requirements by up to two orders of
magnitude compared to raw video" so they also invented mpeg4 level of compression 1mW codec.
You might wonder how such an amazing compression codec works? its middle-out. They transmit "fullhd" by transmitting ~100x50 resolution intra frames ":). Everything is Simulated, Estimated, Planned, Theorized, Calculated and Faked. That cool 1080 YT clip of them walking around the corridor just after showing you face mounted camera models? Never happened, prototype is BW 112×112, "simulated" again. Their setup can do 1080@60 of a static picture, there is only enough bandwidth to sustain ~2fps without dropping data. They even conveniently kept all the calculations ignoring color (3x the data).
Reminds me of energy harvesting wristwatch crowdfunding HN was raving about few months back, conveniently ignoring particular design including battery able to power it for couple of years.
try 10-20 days if you believe in their simulated 800uW ASIC with magic middle out compression.
Assuming everything works according to their predictions and simulations (nothing was actually build to confirm that) you have to pump 1W from your cellphone to power 1mW wearable camera. Your cellphone will run out of battery after 4-6 hours.
Think about that for a second, they want you to recharge your phone every 6 hours to "save from inconvenience of recharging your wearable". This is they main proposed design, right there in YT presentation.
Actually, there is a lot of great stuff that gets submitted that never gets anywhere.
It would be cool if somehow there was a manually edited "great but never got anywhere" stream for HN.
Edit: Now I've gone and said that, watch this get a 1000 points ;)
> Our current implementation does not account
for security. However, to secure the wireless link between
the camera and reader, we can leverage the fact that our
digital core processes the PWM signal. Each wireless
camera can be assigned a unique pseudo random security
key. Based on this key, the camera’s digital core can
modulate the width of the PWM-encoded pixel value
using an XOR gate. The reader, which knows the security
key, can map the received data to the desired pixel values
by performing the analogous operation.
The tricky bit might be deciding where to start the stream...
However, analog scrambling techniques should still be effective in many cases.
I'm not an engineer, but as I understand it the principles at work here are very similar?
Most people drive and reverse way too fast.
I wonder if compressed sensing would be useful here. In the paper they describe this custom (and seemingly ad-hoc) video compression algorithm that is suitable for the low-power device. Basically, the camera averages blocks of pixels into "super pixels" all in the analog domain, sends these super pixels over the wireless link, and then the receiver can request the individual pixels of any super pixel that seems like it might have changed since the last frame. But with compressed sensing, can't all of this be done by sending random linear combinations of all pixel values (like the single pixel camera)? It seems like then you can avoid the bi-directional link and also get rate adaptation for free.
Also fat looms the length of a car can still cost hundreds of dollars said and done.
Cost of installation is greatly reduced if all you need to do is line it up and rivet it on and there is no need to customise the power system to different cars (ie 12V, 24V) and loom layouts (ie old looms are crappy, hard to get apart for splicing, wires are old and might break during retrofit, some cars have +ive chassis)
You could apply this to other types of sensors, such as perhaps accelerometers or microphones. Device locations could be a smart wearable, a surgical implant, or some kind of hard to reach diagnostic sensor.
I suppose we already use something similar in rfids but I guess the novelty comes from updating sensor data instead of a ROM. Very cool stuff.
"Finally, we design a proof-of-concept prototype with off-the-shelf hardware components that successfully backscatter 720p HD video at 10 fps up to 16 feet."
Which to me reads they have it working in principle the other design will be an optimization.
I'm not worried about sabotage/jamming etc. We are trying to monitor OSHA-violations, accidents, and quality control. If I didn't have to worry about power, I would put multiple cameras in every warehouse aisle, loading dock, and doorway. Local storage is embarrassingly cheap but dragging CAT5/6 all over, supporting ton of PoE switches, and coordinating with facility staff to maintain cameras 20ft up the wall is very expensive and time consuming.
I would also buy like 20 of these for my house and live-stream my mini zoo of prairie dogs, goats, tortoises, and birds.
Edit: Added name
Imagine the current state of blanket surveillance, particularly in dense urban cities like London, but everywhere, invisibly. Cheap, battery-free, weatherproof cameras are a step towards this.
P.S.: The book isn't great, but it's miles better than the film.
But anyone paying attention to what goes viral on social networks should know how cruel and arbitrary people can be in practice.
Recording stuff and not sharing it unless there's good reason seems more humane?
Further, if an action satisfies some person ethic but violates a public rule, many folks will take that action anyway. Violating the speed limit to get a spouse to medical aid. Violating a confidence to stop injury. Things like that.
If a rule is counter to human nature (curiosity, personal safety) then it is likely to be useless.