Submitted by brad on Sat, 2005-08-20 01:30.
I’ve called before for a system of Universal DC Power and I still want it, but there is a partial step we could take.
I have a laptop power supply that comes with a variety of tips. The tips tell (through something as simple as a resistor) the power supply how much voltage and current to supply for the laptop they are designed for. I bought mine for use in an airplane, others are sold that do both 12v and AC power.
I would like to see one designed for the corporate market, rather than the carry-around market. Ones to be left in offices and under conference tables, so that when somebody visits with a laptop, they can plug it in. No need to get out their own supply or eventually no need to bring it.
Unlike the carry-around where you pick your tip and leave the rest, this would have an array of tips, possibly rotating on a click-wheel, or all connected to a switch where one can dial the voltage/polarity/etc.
Some companies take more drastic steps. At Google for example, I notice they have standardized on thinkpads, and so all desks and conference tables have think pad supplies. Everybody is able to roam the building and be sure of laptop power. These supplies, while a bit more expensive, could solve the same problem.
An alternate would be to standardize the special tip that describes the power needed. Everybody could get a tip or pigtail for their laptop and carry just that around. Conference rooms could in fact have single supplies that let you plug in several of the pigtail. Of course that is halfway to my original proposal.
Now it turns out a considerable majority of laptops take either 16 volts or 19 volts. The main rebel is Dell, which uses funny plugs and often over 20v. Some need more current than others, I don’t know if any need current limiting or if simply making the PS capable of 100w would do the trick. Anyway, in this case, we could develop a standard 16v plug (the thinkpad one) and a different standard 19v plug (probably an HP one), in two different shapes and colours, and people with laptops could carry a cheap converter to plug their laptop into it. Over time, laptops might come directly able to use this, if they aren’t already — on our path to a smarter power bus. Then people could say, “Oh, you have the orange plug. Great, I can plug my laptop into that.” Vendors who make laptops that won’t plug into one of these two will probably think about switching.
Submitted by brad on Fri, 2005-08-05 12:04.
I’m not the first to think about it, since I see a bunch of patent filings related to it, but how hard would it be to have a sensor for windshield fog. Seems to me you could bounce light (UV perhaps which water scatters, though other colours might work) off the windshield to detect if there’s fog on the inside and use that to control the defogger.
In particular, modern defoggers use the air conditioner which provides dehumidified air when you heat it up again, great for defogging. But also fuel inefficient. I swear that while today’s AC based defoggers are better than the old pure heat ones, I think the AC-off mode of modern defoggers is not as good as the AC-less mode of the old ones.
Anyway, the sensor could at least control if the AC is used, if nothing else.
Submitted by brad on Mon, 2005-08-01 12:06.
Mapping programs, and fancy GPSs come with map databases that will, among other things, plot routes for you and estimate the time to travel them. That’s great, but they are often wrong in a number of ways. Sometimes the streets are wrong (missing, really just a trail, etc.) and they just do a rough estimation of travel time.
Yet all the information is there, being collected constantly by every car that drives the roads with a GPS. Aggregating this data will tell you what roads are real, what roads might be missing, which are one-way, where freeway entrances and exists really are.
And it will also tell you real-world speed examples at various times and dates, at rush hour or otherwise. Even a range of speeds so you can know the speeds for faster and slower drivers and get a really good estimate of your own likely speed on a given road at a given time. After removing the anomalies (like people stopping for coffee) of course.
Rental cars with GPSs are collecting this all the time (sometimes to nefarious uses, like charging whopping fees for brief trips out of state). Technically this data can be had.
But here’s the bad part — there is a potential for giant privacy troubles unless this is done very well, and some may be impossible to do without a privacy risk. After all, until you upload the data, there is clearly a log of your travels sitting there to be used against you. Only a system with rapid upload (and which discards data that gets old, even if it’s not uploaded) would not create a large risk of something coming back to haunt you.
The data would have to be anonymized, of course, and that’s harder than it sounds. After all, your GPS logs say a lot about you even without your name. Most would identify where you live, though that can be mitigated by breaking them up into anonymized fragments to a degree. Likewise they’ll identify where you work or shop or who you visit, all of which could be traced back to you.
So here’s the Solve This aspect of this problem. Getting good data would be really handy. So how do we do it without creating a surveillance nightmare?
Submitted by brad on Tue, 2005-07-12 16:08.
When you take pictures on the road, you would love to have the latitude and longitude coordinates of each picture stored with it. Indeed, if combined with a digital compass clever software could even tell you what landmark was in the photograph. (ie. if standing on rim of Grand Canyon looking north, it's probably a picture of the canyon.)
To attain this, some digital cameras allow you to plug a GPS into the camera, which is unwieldy to say the least. There's been talk of a bluetooth connection which is better but uses power. On a recent trip Kathryn suggested that the log from the GPS could later be matched up with the timestamps of the photos, which is a great idea -- and a web search reveals a few software packages out there do indeed do this. (And thus also allow photo organizing by geographic location, map-based browsing of photos and other such useful features.)
For the user not wanting to hook up all the devices and use software, I came up with a possible interesting design. Place a memory card slot in the GPS, or allow it to plug in USB or other memory card interfaces. The GPS could then look over the photos on an inserted memory card, read their timestamps, and use its own onboard history of where the GPS was at those exact times, and write coordinates into the files on the flash card. If it can write them on the end of the file that's easiest, if it has to rewrite each entire file that would be a bit slower.
Most digital cameras also have their own USB interface, so the GPS could simply have a USB controller and the camera could be plugged into the GPS after shooting to update the photo files with their location stamps. Most, though perhaps not all digital cameras can act like a USB drive in addition to doing camera control. Of course a standard protocol for updating locations would make this easier, but the main idea allows work with existing digital cameras. (Though they all have their own custom USB plugs and provide their own cable.)
As noted, this can give you great photo organizing. You can see your photos as thumbnails or pushpins in a map. You could link photos to google maps or satellite imagrery of the area. Directories on disk could be created by placename, or even without names photos could be grouped by each major shooting area, instead of just one new directory per 100 photos.
The cameras will eventually get smart enough to be the smart device, but for now the GPS can easily be it. Older GPSs don't have very large track log memories, but today memory is cheap and that's not as much of an issue.
Submitted by brad on Thu, 2005-06-23 22:43.
Right now the push in displays is all for computer and TV displays, with fast response time, and ideally in a flat form-factor. But these are expensive, really expensive if you want more than 2 megapixels.
What if we bring back an old technology — long persistence phosphors — and use them to make displays intended for still images, such as photography and art, at high resolution. They are cheap and bright. And if you don’t need to do 60 frames/second, you can also get away with cheap electronics are more resolution per persisting frame.
It would be easy to start with black and white. B&W displays require just a screen of phosphor and a way to excite it. The resolution can be extremely high. Colour requires a shadow mask style technology, or projection such as CRT projection. A portal in the wall for say 10 to 20 megapixel B&W photographs and art might be a desireable product for the home. But there’s hardly any limit for B&W.
There is a limit for CRTs, it get expensive to make a tube that big. New technologies are allowing the electron gun to not be far at the back so it need not be as deep as it is wide, but these are also heavy and fragile. CRT projection (mounted in the roof) might be a good answer.
There are however lots of ultraviolet phosphors which could be triggered by a UV laser or other such source, for rooftop projection or rear projection. If the persistence is long enough so you only have to do a few frames per second you can get in lots of resolution I would think. What would you pay for a 30 megapixel portal in your wall, one as sharp as a window (but not moving and only in 2D of course) showing scenes of the world, and great photography and art?
Submitted by brad on Thu, 2005-05-26 11:41.
I recently read the story of the coffee shop that's shutting down their free wifi on weekends because it mostly gets them moochers who, far worse than simply not buying anything, sit and stare at computers and don't talk to anybody. They found that when they shut down the free network, they not only got people to buy more coffee, the place was also more social.
So while there are a variety of solutions to sell or control access to a network, such as printing tokens that give a period of access on every receipt, or selling the access as they do at Starbucks, here's another idea -- intermittent access.
In such a system the access point lets you on for a modest amount of time. Enough for a quick web search or two, a checking of your e-mail or even a modest phone call. Then it denies you access. It doesn't have to deny it for long, perhaps just 5 minutes before you can get on again. No authentication, though during the period of denied access, it may redirect all web requests to a page that explains the situation, and optionally offers continuous access for money.
Though that's not the main goal. The main goal is to create an atmosphere where you're coming to the shop to do other than stare at your computer, but in which you can use it on occasion to get your fix.
Who knows, if the sale option for continuous access was popular, it might even make more money than an always charging system. Of course, fancy users could change their MAC address to get around it -- but if they're going to go that far, let them. Most won't. read more »
Submitted by brad on Thu, 2005-05-19 09:30.
I shoot with an SLR, and all lenses need a rear lens cap when not on the camera. Every SLR shooter knows the three-handed ritual. (Four handed if the Camera's not on a strap.) You take one lens off the camera. You pick another lens and remove the rear cap from it. Holding the old lens, new lens and rear cap and camera, you put the new lens on the camera, then put the rear cap on the old lens. (Or you put the cap on the old lens first, put it down and put the new lens on the camera.)
Anyway, a simple invention I have already built is a doubleheaded rear lens cap, namely two lens caps glued together. Custom-built it would be a lot smaller and solve some of the problems I have experienced.
With the doubleheader, you can take your lens off the camera and put it immediately onto the open end of the doubleheader cap on the new lens. Then with a twist you remove the new lens from the resulting docked lens pair, and put it on the camera. In theory one less hand or less dexterity.
However, the catch is the docked lens configuration tightens both as you twist one way and loosens both as you twist the other way. So you must master the art of making sure the lens you want comes loose.
How this works varies from lens to lens and how well it fits the rear cap. Sometimes pressing them both together causes one to undo reliably. The most reliable trick is to grab the old lens around the rear neck so you can get a finger on the cap, and then pull the new lens off.
It seems one might be able to design ways to make this more reliable, such as a small flange on the cap to hold with your finger to make sure of what twists off, or a ratcheting twist-off that requires a release button.
If both become equally lose when you untwist, then gravity will help you in that the cap will stay on the lower lens. You must later twist it back to stay on. I think the ideal motion would be to twist on so both are tight, then either hold the cap or release a ratchet so only the lens you want comes off without loosening the old lens. read more »
Submitted by brad on Wed, 2005-02-23 06:23.
Ok, it's strange because I think one of the whole points of the hard disk video recorder / PVR is that you are not supposed to watch live TV any more, not supposed to channel surf -- but I keep coming up with ideas relating to it. Maybe I have a secret desire to surf again.
As many people know, with digital recording, the no-surf rule is enforced because it's harder to do. The digital delay introduces a long channel change delay, intolerable when combined with another delay (satellite/cable box).
Here's a surfing algorithm that could give instant channel change. Surf slightly delayed TV. It works particularly well if the box has multiple tuners.
Using the spare tuner, grab short snippets of every other show that's on right now, or at least everything in the surf list/favourite channels. Just a few seconds of each. As available, update these snippets, with focus on the adjacent channels. If the program changes, you need to grab a new snippet as you must always have the current program.
When the viewer wants to surf, surf not the current live TV but the saved snippets, which will be anwhere from a few seconds to a few minutes old. You will be able to move through them instantly, like the old instant-channel change from an analog TV. You will see the program guide info as well, but the visual clues that we draw upon in surfing will still work fine.
If the user dwells on a channel for longer than the usual surf interval, you will switch the tuner to that channel. You will need to do a nice graphic transition from the surf buffer to the live TV.
Now admittedly, that will sometimes frustrate. It may be the particular scene that attracts your interest -- the bad guy is holding a gun on the good guy, about to shoot, and suddenly it disolves to something a minute later. However, the alternative, which is what we currently get, is that you get black screen for 3 seconds, and then it shows you the later (live) scene. Instead of black screen you get some sample video from an earlier time in the show. The key thing is that the viewer should be aware they are surfing old snippets.
One could also keep snippets of varying lengths from different times, depending on the surfing speed desired. Though usually you would play the longest. You could also develop "smart snippets" which tried to grab the action after coming back from the first commercial break etc. (Problem is those happen on a lot of stations at once.) read more »
Submitted by brad on Tue, 2005-01-11 18:55.
You see it everywhere -- signs on buildings where a light has gone out. It is often amusing where a missing letter changes the name of the company in some silly way.
They spend fortunes on these signs, but bulbs are hard to replace. So why don't they make them with a special unit that has sockets for 2 bulbs, and switches over to the backup when the first one burns out? It's not actually that much more expensive, as you are going to pay for the 2nd bulb eventually (especially incandescent) though here you pay for it earlier.
To get fancy, you want a way for it to tell somebody that a bulb went out. A small data over power chip could constantly squirt simple low-data-rate packets down the power line, "I have a bulb that went out!" Something like the x10 protocol, which can be transmitted by a chip that costs pennies.
Could use that protocol for remote turn on/off as well if you wanted. You would wait for a few bulbs to go out before sending a worker out to replace them. That worker costs more than the spare bulb anyway.
Submitted by brad on Thu, 2005-01-06 06:44.
When you go out hiking and photographing, carrying a tripod can be too much, even my lovely carbon-fiber one. Besides, you want a good hiking stick on a hike anyway, you exercise more of your body. And most hiking sticks have a small tripod screw in them to use as a camera mount.
But here's a plan to make an all-out monopod/hiking stick kit to do a lot more than you can do with just the basic stick.
First, like many sticks, you want a spike end you can stick in the ground with an rubber cap you can put on it. Some monopods have tiny tripod legs that come out of the base that can be used for a light camera on level ground, which is also useful.
However, my alternate proposal takes longer to set up but would be more stable -- guy wires. In this case some retractable strong wires that can be pulled out from near the top of the stick. On the end of the wires you would find, or could attach a means to loop the wire around something (nearby tree, railing) and ratchet to pull tight the wire. You would also have a set of fine ground spikes that could be staked in soft ground and connected to the wire loop, then ratcheted tight. Finally, you cold put weights on the wires, such as rocks, your other gear or a person's foot in a pinch.
The result could be a moderately stable platform, on which you would put your ball head, or in my case panoramic head. Of course weights or thin stakes would not resist a hard shove (though being tied around railings and trees might) but it should be able to handle a fairly heavy camera, since it is the main pole which does that job.
And of course it would all collapse into something 19" long to go in your suitcase. Though you probably couldn't have the stakes in carry-on luggage.
Submitted by brad on Tue, 2005-01-04 05:51.
When you get an ant infestation here in California, you need to make sure your kitchen is clean with nothing to attact them. But if you have pet food out, they will find it.
In theory, ants won't crawl over some materials like vaseline. But if you coat the bowl rim with vaseline, it will get in the pet's hair.
So I suggest a wide pet bowl with a deep and large groove near the base which you can squirt something like vaseline into. It must be wide enough that ants can't do the living bridge trick to cross it, and deep enough that pet hair won't get into the vaseline. That stuff should stay around for quite some time before needing a refill, though if you dishwash the bowl, you will lose it.
Submitted by brad on Mon, 2004-11-01 08:25.
Today the word went around about mypollingplace.com, a site that helps people find their local polling station, running out of bandwidth from their provider and needing somebody to help it.
At the same time I did an interview for opinions about bitTorrent, and the idea came to me that a really useful application would be a P2P generalized web hosting tool aimed at spikes.
Volunteers who have a reachable IP address (including people who can open holes in NATs) would install software to volunteer to help host sites in need during a spike. This could be client software in a browser or permanent server software.
Then a few different things could happen. Ideally a site would install a tool which activated the sharing network when their load got high (but well before their provider cut them off.) People fetching static pages that weren’t sharing bandwidth would be redirected to a port willing to share. The page would also be modified to encourage folks to join the process. Folks who were willing to share might get access or be redirected, and they would cache the page, declare where it resides and serve it there for some period of time or number of hits.
If a site didn’t install the fancy redirector, they could redirect all web hits to a volunteer tracker that would do a further redirect to a real location willing to host the item.
Finally, for sites totally unaware of this, a browser plug-in could notice when access to a page is very slow or gets a “bandwidth limit exceeded” message. It could then query to see if any of the P2P folks have cached the page, and fetch from there, or offer the user a button to check or fetch from that network.
This latter mode is good because it strongly encourages having the magic plug-in with your browser. If you don’t have it, you can’t get at the P2P cache.
I’ve been informed that Coral from NYU does some of this, though it doesn’t do the “on demand” aspect that leaves the web in normal state when not overloaded, and switches to cacheing only when needed. With Coral and other redirects, your Google adsense doesn’t show up either! read more »
Submitted by brad on Mon, 2004-10-25 17:08.
Many people like the idea of soda fountains, but the official fountains that mix soda and pre-mix concentrate are quite expensive and work to maintain.
To gain some of the convenience and efficiency, how about a quasi-real fountain using existing 2-liter pop bottles? Such a fountain would be designed to look like a regular one. Inside, ordinary 2-liter bottles would be attached. In a "party" model, they would just be in an icebox, in a full-time model it would have refrigeration.
To attach the bottles, their caps would be removed and a special cap screwed on that would have two hoses -- one for pop to come out, and the other for gas (CO2 or air) to come in to push out the drink. A CO2 cylinder could power this, or an air pump if you want battery power. Gravity might be able to do it but pressure certainly could.
The special caps would have another quick connect interface that lets them be turned upside down and snapped into place. Alternately, the bottles could be in another orientation as long as the feed tube can reach their bottom.
You might want to be able to have two bottles of the same drink feed the same fountain to give more capacity and the ability to drain one and then the other so that they can be "hot swapped" (really cold but you know what I mean.) Or people might prefer to be able to offer lots of different drinks, but just 2L of each.
The goal of this design is to be very cheap. The one based on ice and CO2 cartridges would be very cheap and need no power -- more of a party amusement, but also an efficient way to give people only what they need.
Of course you could just empty the bottles into reservoirs, but then you need a way to clean them. Cleaning the tubes could be done with an attachment for a garden hose to flush them, and the caps could go in a dishwasher.
This is my lowest tech idea yet...
Submitted by brad on Thu, 2004-10-07 05:58.
An out of left-field idea. It doesn't happen a lot, but one of the things people fear deeply is being bitten by a shark. Sharks sometimes bite surfers, because, it is suspected that 4 paddling arms lying on a surfboard triggers the "tasty seal" match in the shark's brain.
(Reportedly sharks don't actually like how we taste that much, and have spit out human limbs they bit off. I dunno, but somehow that's adding insult to major injury.)
Anyway, to stop this there are some products on the market. One is a set of decals in the black and white stripe patterns of poisonous fish sharks don't like to eat. Another is a set of electrodes that send out a strong electric field which sharks hate (they have electric sensing organs that most fish don't.)
Here's another idea, for all the surfboard shark repellant readers of my blog out there. Since the shark looks up at the board against the glittering surface, patterns on the bottom may not be enough. But what about new bright but low power LEDs? Possibly an animated pattern moving over the LEDs to say "not food" to the shark. First of all such light is highly non-natural (at least not from prey) and can be made to move in very artificial ways, or natural ways that signal non-prey. And today, the power for it is not very much. Here's where we need the advice of all the trained icthyologists reading the blog.
Submitted by brad on Sun, 2004-10-03 11:49.
Tested my UPS systems and found them wanting in Friday's 10 hour Cupertino blackout. Last week I wrote about my longtime desire for a PC power supply that let you plug in an external battery for a cheap, long lasting UPS. But here are some other ideas.
Generally you don't want to plug your monitor into your UPS, because it will drain it faster, which is pointless if you are not there. Better energy-conserving monitors with screen-blanking screen savers can do something about this, but why waste any power on a monitor you're not looking at. I've taken to leaving the monitor off of the UPS power, and then when I come to the computer to do something, plugged the monitor into the UPS. Of course that can require a flashlight and wastes precious time.
So let's have a plug on the UPS that is switched. By default it only takes mains power, even during a failure. But during a failure you can push a button and it switches to the backup power. Perhaps have more than one of these, and plug all your optional devices into them. (For workstations, for example, you may want to only power network hubs or DSL modems when you are there, though I usually go the reverse path.)
Of course, since often the computer has a data link to the UPS, you could even have the computer tell the UPS to power on the optional plugs if the person is at the keyboard.
One could also build a fancy switched plug to do this though I don't know if anybody makes such off the shelf. That might be a simpler product. read more »
Submitted by brad on Mon, 2004-09-27 13:07.
I like fine camera lenses, but the best quality are very expensive. There are many things that are hard to do in a good lens -- you want a sharp image, of course, over the full flat plane. Over the whole image plane you want low flare, high contrast and low chromatic abberation (ie. red and blue focus in the same spot.) And you want low distortions.
Most camera lenses try to be "rectilinear." That means they try to make a straight line straight in the image. This isn't actually natural, due to perspective straight lines are not straight.
So I wonder if we might soon see a new lens where no effort is made to fix distortions or make the image rectilinear, and all effort goes into the other factors. You are thus expected, with every image, to do digital post-processing to get a non-distorted rectilinear image. That will mean some small loss of image quality at the edges of the image, but probably a less distorted image than ordinary lens physics can deliver -- and a lot less cost -- in exchange.
Of course, this would primarily be for digital cameras, but a film user could also use the lens if they planned to scan their film for digital processing, as most do these days.
Down the road, each lens might contain within it the specifics of its own particular distortions, and the camera might be able to fetch this and either process directly or store it with the image for post-processing. Indeed, the lens might be a cheaply made lens with distortions due to the poor quality elements, or it might be a fine lens with deliberate distortions. (I have wondered if some P&S digicams might be doing this already.) read more »
Submitted by brad on Wed, 2004-09-22 07:21.
Generally, getting a case to use a camera underwater is expensive. The case has to be custom made for the particular camera, and it has to be full of waterproof push-through button-pushers for all the major controls. Digital cameras have helped a lot, since they can shoot far longer on a "roll" and things like zoom are electronic. They also sell in enough volume that some cases have gotten down to reasonable prices.
But more is possible because most modern digital cameras feature complete electronic control, either by USB or via infrared. This should make it possible to build a generic underwater camera case for whole classes of digital cameras of a certain size. The case itself can be very simple, with no holes or button gaskets. For cameras without infrared remote (or where the IR remote does nothing but a couple of buttons), a small USB to IR converter would allow complete control.
The box is simple, the real brains would be in an underwater-capable IR remote control carried or mounted on the outside of the case. It would need personality modules for new models of cameras but otherwise could be pretty much the same as well.
So you get a much simpler box and you get mass production because you can sell it for any camera. And you can keep it for your next camera. It's a bit bulkier, but that's about it. And it can offer more controls, even some controls that aren't even on the camera in some cases.
Zoom can be a bit tricky. You want to avoid glare off the plexi at the front when the lens isn't up against it. It's possible that might be designed to telescope when you change zoom settings, or the camera itself might gently move in an inner frame. Or it might just have a black bellows "hood" in the space between the lens and the view panel. This problem also exists in custom cases of course.
The same idea could also be applied to above-ground protection in harsh environments (snow, rain, dust etc.) for expensive cameras. There you don't need a pressure seal, just a thick bag with the same remote ability. Shoot happily in the rain.
Submitted by brad on Tue, 2004-09-21 09:30.
RVs come in all sizes, from 40’ bus to towable pop-up. But what about inflatable in a trunk in the back of a minivan?
Setting up and tearing down tented campsites is a pain, and there are instant-setup tents and even some inflatable tents. But what about a super-duper inflatable tent, designed for car-camping.
In the cabin-tent structure with high-pressure frame would also be (at lower pressure) one or more built in airbeds (that you leave the bedding on), an inflatable couch or chairs, wiring for LED or fluorescent lights in the roof with switches, 12v power jacks etc. On the outside might be an inflatable sink with 12v pump and drain hose and outside inflatable chairs. There would be an “air pressure bus” with quick-connects and turnable valves for each component. Inflation would be pushbutton, deflation might require turning values as you deflate components but still simple. Once deflated, the whole thing — components, bedding and all — would roll up and fit into a trunk or large suitcase that would fit in the back of a minivan or SUV. It would not be designed to be small or light like most tents.
It could also be designed to sit in a hitch holder, along with a bike rack. Add a portable toilet, camp stove, ice chest and folding tables (inflatables are not solid enough.) Ideally wire a special jack into the van battery, and replace the van battery with a marine battery (deep cycle and starting).
The goal: open the crate, open the valves and start the compressor. In a few minutes, a living space is erect. If needed, put in weights or stake it down. In the morning, start the vacuum on the internal components, then turn the valves to drain the support members, roll it up, bedding and all, and go.
I believe this could easily sell for $1,000 or more. It would be almost as easy as a pop-up camper, but best of all you would not be towing something. It would pay for itself for families on a cross country road trip pretty quickly. The key is to not think of it as a tent but as an RV.
Submitted by brad on Tue, 2004-09-14 09:25.
I finally watched the closing ceremonies yesterday (did not see them while at Burning Man, obviously.) I liked the blinky balls that the children and audience members had, and the sense that the flame lit the LED ball. But it was just manual, people pushed buttons.
It occured to me it would not be too expensive to make an LED blinky that worked a bit like flame. While it was on, it would transmit a particular signature code in its blinking. If another blinky got close enough to see this brightly enough, it would detect it and turn itself on for some period of time. You could tune the range, it's just a photoresistor.
That way they could "light" their neighbours the way a flame does, and the flame would pass along. With the range tuned to a few feet, the lighting would have propagated through the audience at some speed (you could define what the speed would be.)
This would also be a fun rave/party favour. You might be able to light your own or you could light from somebody else. Perhaps after too long alone the blinky would go out and need to be lighted from somebody else's, encouraging socialization.
Submitted by brad on Mon, 2004-09-13 11:53.
We all would love solar power to work better, but it's hard to have it make economic sense yet, at least if you're near the grid. A solar panel takes 4 years just to give back the energy it took to build it, and it never pays back the money put in if you compare it to putting the money into the stock market. And that's with full utilization. If you use panels and batteries, any time your batteries are near full the power is being discarded, and you also have to replace your batteries every so often and dispose of the old lead-filled ones. Yuk. A grid-tie can use all the power of a panel but that's an expensive, whole-house thing.
But here's a start -- a solar-using PC power supply. My PCs, like many folks', are on all day, including the peak-demand heat of the day. Desktops draw anywhere from 50 to 200 watts even when idling.
So make a PC power supply that has 3 external connections. One for the wall plug. And two optional ones, one for a 12v solar panel and one for a battery. Then sell it with a 50w or 100w solar panel -- most importantly, the panel should not ever generate more power than the PC uses.
Because of that, during the bright part of the day, the panel will be providing most, or just barely all, of the power for the PC. The wall plug will provide the rest. At night, the wall plug would provide all the power. It's a grid-tie but it doesn't feed power back to the grid, it just reduces demand on it. The 100w panel takes 100w off the grid load during the peak demand times. And we use every watt the panel generates, we never throw any away. read more »