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Joined 9 months ago
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Cake day: October 11th, 2023

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  • MAPLE, which is super cool:

    As I understand it, the primary goal of the MAPLE project is to demonstrate interference beam management on a space-borne object, which is incredibly cool. I’m not able to find the actual paper (it’s very possible it simply hasn’t been finished yet, it looks like the experiment is ongoing) but it’s extremely interesting technology. However, atmospheric attenuation is going to reduce the power from what sounds like maybe a milliwatt to infinitesimal amounts. The reason this technology might be able to beam power to anywhere is that being in space means you have access to essentially unlimited power. There’s no real-estate concerns, so you can put as many solar panels as you want up there, and thus you don’t have to care about losses.

    Obviously there’s some engineering realities that might conflict the “unlimited power” bit, but I’m glossing over things like we have a limited amount of silicon with which to make solar panels and so forth. However, since this technology is in it’s absolute infancy, it’s hard to draw conclusions. It may not work at all, and the power being beamed down is in a unit smaller than nanowatts. It’s just too new of a technology to know if it even works, given these articles are from about 6 months ago and are talking about the 6 months worth of data crunching the team has to do, I really doubt we’ll hear anything substantive any time soon.

    Roads that charge cars:

    These will never work. Not for theory reasons, but engineering realities I won’t gloss over. To be clear, there’s no physics-founded reason we couldn’t stick multiple overlapping inductive loops on the surface of every single road and power cars that way, it’s just that inductive charging is incredibly inefficient, so the power you’re pumping through all those loops in every road to charge up an electric car will be astronomical. And god forbid there’s potholes, exposing those insanely high amperage coils. (And before you ask, the dwell time of an electric car at a red light is so short as to be practically nonexistent). This is the same issue as the solar road tiles - it just doesn’t work to do it like this, and there’s much better and more efficient ways to use those resources that would go into the roads. And no, inductive coupling like in these roads is not RF-to-DC power transmission (unless you want to get really really pedantic about particle physics…)

    A watt or two to trickle feed the phone:

    Unfortunately there’s this thing called the inverse-square law, which doesn’t stop applying even when you have highly directional antennas. I’ll spare you the math (lets be honest, I’m too lazy to type and format it all up), but the takeaway is that to get a couple watts you’ll need hundreds of watts being output by the transmitter, and that’s just for a couple feet of transmission. And lets be clear, this is absolutely not safe. “This is literally radiation damage to your cellular structure” levels of not safe. For a simulation of what it would take to get enough power to meaningfully charge a phone at 10’, go jam something into the door latch on your microwave, open the door and stand 5’ away from it. That’s the power we’re talking about here. (please don’t do this, it’s an even worse idea than it sounds). It would be illegal to sell transmitters this powerful for consumer applications, because with much exposure it would kill you.

    I want to be clear about something, systems that work on similar principals to this do work and they are in use today. You can even see videos of one of the umpteen billion “wireless power” companies that’s pulled this same shtick on kickstarter or wherever, there’s been dozens of them. They have videos of them charging a phone! Of course, they’re not really charging the phone, they just use a capacitor bank that’s trickle charged from an antenna array (which then pulses the charges so you phone trips into charging mode, but it won’t actually charge, it will just turn the icon on on your phone…) or, in several cases, just a battery pack hidden off screen. The systems that do work, and that we have in operation, transmit minuscule amounts of power. Way less than you could use to light an LED. They’re just used for powering incredibly lower power equipment, like RFID tags or the tattletale strips in stores. Power transmission just loses too much energy while being transmitted for this to ever be practical for anything more than that. Maybe MAPLE will change this, interference modulation turning out to be the holy grail of aiming ultra-tight beams, but I’m pretty skeptical that it will do anything on the consumer scale.



  • (I haven’t slept in entirely too long so my apologies if my prose is somewhat lacking here)

    CES awards really are deserving of my initial sarcasm. Most of these awards are. You usually can’t literally just buy them, but the process is pretty much no different. There’s no evaluation of quality, effectiveness, or even basic things like “does it meet the claims made on the box” made before they’re given out. And I hate to pull the ‘godwin’s law’ of investor cautionary tales, but take Theranos. How many awards did it win? I don’t know, because I got bored counting after thirty, but they clearly didn’t mean much. And I’ll grant you, it’s not the perfect example I’d like it to be, because Theranos’ claims were based on medical biology and that’s a bit out of scope for what would be reasonable of CES judges in a perfect world and Ossia is first-year physics or the HAM extra exam.

    What my point here is, is that we already have this technology, and it’s used every day. But the applications here are incredibly specific: inventory control, both realtime monitoring and loss prevention (RFID tattletail stickers are on everything nowadays) and similar applications, where it powers essentially an RFID tag that consumes power in the microwatts. There are systems that can transmit Watts of end-point power, but those systems are close range (3’-4’) and very dangerous for humans to work around. It’s radiation, man!

    Look, it’s just physically not possible for them to be transmitting the power to run (examples taken from their website) [a television, your Phone, a tablet] over any great distance (more than 3"-4"), and have that device be safe for people to be around. Yes, microwave power transmission is possible, famously you can heat your coffee on a field broadcast transmitter, but it’s not possible to provide an end result of ~5W of power across your living room without incidentally giving you some novel form of skin cancer. Even their directed antenna tech just… can’t change the laws of physics like this.


  • Huh, neat. Sincerely, what part of that seems undeserved? Here, I’ll explain my perspective:

    The parent comment that really caught my attention includes such wisdom as:

    I follow along with what I am told. If someone says they can do it. Show that it can be accomplished. You pop up and say actually it can’t and here’s why. Believing either of you is a toss up. Both come to the table with evidence.

    Which really just speaks for itself there. It’s “both sides” but with easily disproved corporate claims, being advocated for as totally reasonable and “I choose to believe”. It’s like tech bro fundamentalism, but… lame (edit: lamer). Also, while calling me “not a tesla investor advocate” barely warrants being called an ad hominem attack, like… come on. I’m not above rising to personal attacks, especially when I can quite clearly lay out why they’re an ignorant schlub. (also also, it’s hilariously wrong. Tesla was a very good investment and anyone could see that, including me, who owned Tesla stock. It’s er… slightly less so as time has progressed, but tenish years ago? yeah, jumped on that band wagon, worked out for me… Also, that’s just… the dumbest insult. Like come on.)

    I think you’re so caught up in your own self-righteous drive for civil internet discourse you’ve forgotten that

    1: Other people online are perfectly aware of the tone they communicate through their comments, and chose that tone deliberately.

    2: Sometimes, being rude and/or condescending is totally reasonable.

    Like for example here, where someone is seemingly advocating for people to invest in a company (or justifying their own stupid, stupid choice) that is at very best grossly misrepresenting the product, and at worst just doing straight up investor fraud. Also, a company where their product claims are fundamentally impossible, and I can back that up with math. I might have been raised in some wildly different culture than you, with wildly different values, but I will say that I suspect your culture and mine both put a high social value on calling out rampant BS when it runs the risk of affecting other people in your community. This? This worthy of being scorned.

    Seriously, maybe consider getting a better grip on that high horse before it runs off and does something interesting with it’s life.


  • Tesla, the famed genius who 100 years ago was scamming rubes with the same impossble promises wattup is peddling? Kinda seems like time has told on that one.

    Listen, Wattup isn’t doing anything new. RF to DC has been around since… well, Tesla. We already use it in the insanely few applications where it’s viable tech. You might even have a few RF to DC devices bolted to your house, solar panels. The problem is that Wattup doesnt have a literal star powering their chips. What was the last device you saw that was fully solar powered (calculator) - how much of the surface area was given over to that component? And how big are wattup’s chips? yeah.

    The power transfer Wattup promises is admittedly an impressive improvement in power while still staying within FCC guidelines, but go up one class of transmitter and you’re back to playing with tech thats been around for a hundred years. We already use COTS parts for this for indoor mapping, thats what RFID inventory tags are. Or power over NFC devices. It’s useful tech, but wattup hasn’t shown ANY devices that actually hit their pie-in-the-sky performance goals (“recon drones”). One hour with a radio physics textbook and you too can do the math to understand why its never, ever going to happen. it’s not a problem that can be innovated around, it’s fundemental universal laws here.