I thought a useful application of this would be an improved rear-view mirror for a car. Right now, people look at 3 different mirrors (not even placed near each other) and have to form a 3d image of whats behind them from those sources.
Here's my idea: A single wide-screen video monitor that shows a composite video image from a number of cameras around the car. With cameras now small and cheap, you could place two prodtruding from the front of the car, looking back at the driver and the adjacent lanes (some school busses do that with big mirrors, but that wouldn't sell on a passenger car. Plus, the image is too small). Another camera could be behind the rear windshield, giving an unobstructed view out the back.
The composite view would show a view of the front of the car, but the passenger compartment would either be transparent, represented with a wire frame, or be semi-transparent (so the driver could see himself/herself and get a sense of what side of the picture is what). The height of the view could be varied, too -- it could be a sythesized view from about 10 feet above the hood. These are views that would be either impossible to achieve normally (i.e. transparency) or impossible to achieve without a big protruding boom, and would provide a complete merged picture of a number of cameras.
p.s. car manufacturers- I'll sell you a license for my technology, if you want.
It's actually a 2-dimensional DCT (discrete cosine transform), some quantization applied inequally (the low-frequency components are better represented; this is the lossy part), and then entropy-coded (Huffman or arithmetic, aka zip-like lossless compression) in a cool zig-zag fashion. Here's a quick, decent summary.
Close, but not quite. The rate that heat is generated isn't a function of the cooling system; it's a function of the heat-disappating components (and, true, only a high-power processor would have a water-cooling system).
Given an insulated enclosure and non-stopable heat generation, the second best you can do is to evenly distribute the heat among all components (actually, the best you can do is distribute more heat to components that can take the heat - i.e. heat the aluminium just to the point of melting at the same time silicon reaches its melting temperature). A water cooling system would better distribute the heat (as opposed to when I did this- my poor little fan was running, but there was no air in my bag to move).
Here's the page for the Motorola MPC8540 -- the first implementation of the commonly called G5 chip.
G5 seems to be a term that only Apple uses (maybe IBM, too?); Motorola calls this the first implementation of "the e500 high performance core [which] implements the enhanced PowerPC Book E instruction set architecture". They also call it a PowerQUICC communication processor; I suspect they have no shortage of names.
I've been drooling over this chip for a while - RapidIO bus interface, dual 10/100/gigabit ethernet controllers built in, DDR memory controller with ECC, PCI-X... It's got enough stuff to make a great laptop, but is meant more for embedded applications.
Why, when every trend in audio is towards more immersive, bigger speakers, higher fidelity records and reel-to-reel tapes, and quadraphonic sound, does anyone think that a palm-sized low-fidelity "compact casette" 2-channel system through a pair of lightweight (and bass starved) headphones will ever truly work for listening to music?
Every time I listen to a subway performer, the excess reverberations and din of the cars make me feel like I'm listening through a seashell. It seems to me that in order for a new product to be successful, it has to offer something better by a noticable factor than previous products.... and with that last sentence, my friend, you've hit on the exact answer. Well, almost. Form factor. People will find imaginitive uses for this - and, as in the case of the Walkman, portability will offer new and very different ocassions to use the product. Watching a movie may not be the best use, but people will find others... no one caries around pocket video games anymore, but whoever thought that video games on a cell phone (a different form factor) would be so popular?
Bah, if someone wants to get sweaty listening to music, they'll go to the disco where the DJ will have a proper sound system and the necessary funkadelic light show -- none of this "jogging with a pair of headphones".
And when looking for the date code, remember it doesn't have to include the date. If it did, then it would be a simple matter of setting the clock in the player.
A better scheme would be just to use an incrementing "edition" or "volume" number... After playing Starbucks Greatest Hits Volume 10 for 1,000 hours, it could decide that that was enough and from then on, it would play only Volume 11 or higher (and when it saw such a disc, it would reset its playtime counter).
The disadvantage to that scheme is when you decide that, in order to play on all machines, you come out with your own CD labeled "volume 65535", you'll bump up the volume counter in every machine the disc gets played in and they will no longer play the corporate-sanction editions (which haven't reached anywhere near 65535 yet).
Then, there's the implementation of the actual device - it could be easy to get around. If there is a battery or a supercapacitor backing up memory, disconnecting and/or shorting it out would clear the memory. Presumably, the player would get set to a special state where it would play the first volume it read... or (less likely because it would be a pain to maintain) it may require a special initialization CD that tells it what the current volume is.
And if the config data is stored in an EEPROM (either a discrete device, or embedded in some other part, such as the microcontroller), then it gets harder...
good luck, and please report back. Or better yet, send me a unit!
The ipod warranty has been improved to one year, up from its much criticized 90 day warranty. The ipod service page doesn't reflect this new warranty yet... out-of-warranty repairs cost an amazing $256.
Yesterday I read an article in a major newspaper (NYT, WSJ, or washington post - sorry, couldn't find link) describing how many high tech things (including the ipod) didn't come with suitable warranties -- for example, dell just changed from a 3 year to 1 year warranty.
The EETimes article covers a lot of the same ground. Some info from it:
Since Nvidia doesn't have a license to develop for the intel bus, this will interface to AMD processors (uh, despite that the xbox is intel-based). A version for the Hammer is "far along" and may merge north and south bridge functions into one chip.
Four Taiwanese motherboard manufacturers, including Asus and Chaintech, will use the chips
A future version for server line cards may include gigabit ethernet, routing capability, and a HyperTransport link to network processors.
No, neither of you are scientists. Hydrogen is more powerful. Jusy kidding; I'm sure you both knew this already.
There's the old high school experiment: the teacher pops an H-filled balloon with a candle and there's a bang. Then they pop a balloon filled with 2:1 O:H molecule ratio, and repeat the test - an earth shattering kaboom. The trick is to make sure that the 2 elements to burn are well mixed -- that's why dynamite (whose molecules include ready-to-react oxygen) is so much more effective than gunpowder (which is coarsely mixed with oxygen). Heck, even flour is explosive when mixed with the right proportion of air in a silo
I had a friend who was constantly (once per hour) checking the progress of his package via Fedex. So, I mirrored the Fedex website and changed the "hosts" file of a lab computer to point to my mirror's IP. Imagine his surprise when he logs into the *correct* website, types in his tracking number, and finds that the package was last checked into a flooded sorting facility and it should take a week for them to pump out all the water and dry out the packages!
I wish someone would make something like this for the car. There are multi-disc changers, but they hold, at most, 10 cds and are often mounted in the trunk. I'd love the versatility of a large range of music, without...
- having to juggle which cds are in my car and are in my house - the mess of many cds sitting around in the car - not being able to play a cd because it wouldn't be safe drive while trying to find it - the chance that my cds will be stolen/damaged
MP3 cd players are nice, but I still have to select a playlist and keep the cd up-to-date with my favorites.
Here's the video (2.8 MB). It should take about 10 more minutes to ftp up. There is no soundtrack, so I'll give the narration here:
The satellite is called GEMstar and was designed to provide SMS-like messaging all over the world. It was built circa 1994-5 and was lost when the rocket blew up. That didn't stop me from producing the video of what it would have looked like!
The video shows a couple of stages that occur when the satellite is released from the rocket. First, it initially tumbles. Then the solar panels deploy (like everything else, they had to be squeezed in to fit in the nosecone of the rocket). The attitude control system (ACS) turns on and stabalizes the spin of the satellite so that it faces towards the earth. This is done with momentum wheels (heavy wheels inside the satellite) and torq coils (coils that act against the earth's magnetic field). Next, the main helicial antenna is deployed, and it's ready for service!
A few notes on the parts of the satellite. The blue panels are solar cells. The gold ring at the bottom is the seperation ring that attaches the whole thing to the rocket. The 4 white squares on top are GPS antennas connected to a special receiver that can measure the phase difference between the antennas and therefore figure out (not only x,y,z and time) its pitch, roll, and yaw. The X-shaped thing on the top of the satellite is a gravity gradient boom. Deployment of this probably should have been in the video, but oh well. It pops out maybe 10 feet and, due to some simple physics I don't understand, will help orient the satellite so that it faces the earth. (In reality, the satellite isn't staying still, it has to constantly re-aim to keep pointing at the earth). On the side panel, the little circle is a window for the earth sensor. There is another one on the other side, and they help orient the satellite.
Antennas- The 4 blade antennas are for command & control. These form a broad pattern and are useful to talk to the satelite when the main antennas aren't pointed correctly (like when there is a problem). Being a broader pattern, they require more power.
The boom antenna has two elements - a larger 150 Mhz antenna to receive transmissions from ground users (who transmit on less licensed taxicab-like frequencies), and a smaller ~400 MHz transmit antenna at the tip. This antenna was the hardest part of the animation because there were no 'spiral' primitives in POVray. I ended up writing a little program in C to generate a bunch of triangle strips, and then used 4 copies of this (at 90, 180, and 270 degrees). The deployment is totally bogus - I just scaled the structure, when in reality the width of the strips don't change.
True story: our competitor at the time was Orbital with their series of ORBcomm satellites. They used a similar antenna structure, but theirs folded up sideways, like a staw that has been rolled up. Our antenna was made of metal, plastic, and fiberglass - theirs was made of copper tape, kapton (a space-rated scotch tape), and bamboo. I never thought that anyone would fly a wooden satellite!
more technical info
on
Making the iPod
·
· Score: 4, Informative
I found that ppmtompeg already installed with my RedHat distribution. I found my old pictures off of my backup CD (which was taken from my backup SyQuest EZ-Drive 135) - it turns out that there were 500 frames @ 640x480, so it's 15 seconds of FULL SCREEN bliss! I got it all set up, wrote the parameter file, and then.... nothing. I ran it with strace- it parses the parameter file correctly, but then it doesn't even attempt open up my first frame. Thanks again; now I've got lots more options to try!
I worked at a company building a small satellite. For fun in my few off hours, I did a POVray animation illustrating the various stages of deployment - the solar cells deploy, then the first antenna, then the second, etc. I did a small animation on my 100MHz 486 laptop and management commissioned a high quality large animation to be done in 4 days.
I rigged up 13 unsuspecting computers at the office - just about our entire inventory of brand new P90's. Imagine - over a Gigahertz of processing power at my disposal! Luckily, I had been dabbling in multiprocessing and wrote a simple client and server software to manage it all. Each frame took about 30 minute to render, and the whole thing was done in about 12 hours (300 frames=10 seconds of video).
The file size was huge - 300 frames of 800x600 uncompressed TGA's = 412 MB. We only had an internal network, so we couldn't use the internet to send it. Luckily, I had just bought a new laptop with a still-mostly-empty 800 MB hard drive. I used a parallel cable to transfer the files onto the drive (If I didn't, I would have filled the network drive), and when I got to the place that was going to transfer the images to video tape, I used laplink again to put the data on their machine (filling their drive, too!).
Eventually, I'd like to make an mpeg of it so I can show friends. Any suggestions for a free encoder?
We had a room-sized temperature chamber for baking/freezing satellites that used water cooling. When we'd fire it up, we rolled out a fire hose (literally!) into the parking lot, so that it could drain into the sewer. Technically it's not legal to put treated water into the storm sewer system (it's for rainwater, not chlorinated water), so we were quick to roll it back up.
I'd recommend this book: High Performance Computing. It covers this trick and many others -- if your compiler doesn't do them automatically, then you can hand code it.
Actually, that's not the issue. The issue is who owns the keys.
In the the first case, the user has control of the crypto keys and uses it to determine what data to accept into his or her computer, use it to make sure outgoing data securely makes it to its intended destination.
In the second case, the keys are held by the manufacturer of the hardware and the operating system. They determine how a user's computer can be used.
Being forced to use encryption/authentication is not a problem at all; just as long as I can control what things I think are acceptable. I use linux and my files have different levels of access - user, group, superuser - but, as long as I have root on my computer (and no one else does), file access restrictions are a security great benefit to me.
Slashdot Mirror
I thought a useful application of this would be an improved rear-view mirror for a car. Right now, people look at 3 different mirrors (not even placed near each other) and have to form a 3d image of whats behind them from those sources.
Here's my idea:
A single wide-screen video monitor that shows a composite video image from a number of cameras around the car. With cameras now small and cheap, you could place two prodtruding from the front of the car, looking back at the driver and the adjacent lanes (some school busses do that with big mirrors, but that wouldn't sell on a passenger car. Plus, the image is too small). Another camera could be behind the rear windshield, giving an unobstructed view out the back.
The composite view would show a view of the front of the car, but the passenger compartment would either be transparent, represented with a wire frame, or be semi-transparent (so the driver could see himself/herself and get a sense of what side of the picture is what). The height of the view could be varied, too -- it could be a sythesized view from about 10 feet above the hood. These are views that would be either impossible to achieve normally (i.e. transparency) or impossible to achieve without a big protruding boom, and would provide a complete merged picture of a number of cameras.
p.s. car manufacturers- I'll sell you a license for my technology, if you want.
It's actually a 2-dimensional DCT (discrete cosine transform), some quantization applied inequally (the low-frequency components are better represented; this is the lossy part), and then entropy-coded (Huffman or arithmetic, aka zip-like lossless compression) in a cool zig-zag fashion. Here's a quick, decent summary.
It's a japan-only model for exactly that reason. It'll be a long wait until it's available in
Ottawa
Close, but not quite. The rate that heat is generated isn't a function of the cooling system; it's a function of the heat-disappating components (and, true, only a high-power processor would have a water-cooling system).
Given an insulated enclosure and non-stopable heat generation, the second best you can do is to evenly distribute the heat among all components (actually, the best you can do is distribute more heat to components that can take the heat - i.e. heat the aluminium just to the point of melting at the same time silicon reaches its melting temperature). A water cooling system would better distribute the heat (as opposed to when I did this- my poor little fan was running, but there was no air in my bag to move).
Here's the page for the Motorola MPC8540 -- the first implementation of the commonly called G5 chip.
G5 seems to be a term that only Apple uses (maybe IBM, too?); Motorola calls this the first implementation of "the e500 high performance core [which] implements the enhanced PowerPC Book E instruction set architecture". They also call it a PowerQUICC communication processor; I suspect they have no shortage of names.
I've been drooling over this chip for a while - RapidIO bus interface, dual 10/100/gigabit ethernet controllers built in, DDR memory controller with ECC, PCI-X... It's got enough stuff to make a great laptop, but is meant more for embedded applications.
whoops.. credit where credit is due: Jeff Brown did the animation based on the paper (linked above) by David Moore.
from the original analysis by David Moore:
.FLI) .mov {requires QuickTime v3 or newer} )
UK Mirror
UK FTP
AU Mirror
Flipbook animation (207k
Quicktime animation of growth by geographic breakdown (200K
original www.caida.org gif animation
Why, when every trend in audio is towards more immersive, bigger speakers, higher fidelity records and reel-to-reel tapes, and quadraphonic sound, does anyone think that a palm-sized low-fidelity "compact casette" 2-channel system through a pair of lightweight (and bass starved) headphones will ever truly work for listening to music?
... and with that last sentence, my friend, you've hit on the exact answer. Well, almost. Form factor. People will find imaginitive uses for this - and, as in the case of the Walkman, portability will offer new and very different ocassions to use the product. Watching a movie may not be the best use, but people will find others... no one caries around pocket video games anymore, but whoever thought that video games on a cell phone (a different form factor) would be so popular?
Every time I listen to a subway performer, the excess reverberations and din of the cars make me feel like I'm listening through a seashell. It seems to me that in order for a new product to be successful, it has to offer something better by a noticable factor than previous products.
Bah, if someone wants to get sweaty listening to music, they'll go to the disco where the DJ will have a proper sound system and the necessary funkadelic light show -- none of this "jogging with a pair of headphones".
And when looking for the date code, remember it doesn't have to include the date. If it did, then it would be a simple matter of setting the clock in the player.
A better scheme would be just to use an incrementing "edition" or "volume" number... After playing Starbucks Greatest Hits Volume 10 for 1,000 hours, it could decide that that was enough and from then on, it would play only Volume 11 or higher (and when it saw such a disc, it would reset its playtime counter).
The disadvantage to that scheme is when you decide that, in order to play on all machines, you come out with your own CD labeled "volume 65535", you'll bump up the volume counter in every machine the disc gets played in and they will no longer play the corporate-sanction editions (which haven't reached anywhere near 65535 yet).
Then, there's the implementation of the actual device - it could be easy to get around. If there is a battery or a supercapacitor backing up memory, disconnecting and/or shorting it out would clear the memory. Presumably, the player would get set to a special state where it would play the first volume it read... or (less likely because it would be a pain to maintain) it may require a special initialization CD that tells it what the current volume is.
And if the config data is stored in an EEPROM (either a discrete device, or embedded in some other part, such as the microcontroller), then it gets harder...
good luck, and please report back. Or better yet, send me a unit!
The ipod warranty has been improved to one year, up from its much criticized 90 day warranty. The ipod service page doesn't reflect this new warranty yet... out-of-warranty repairs cost an amazing $256.
Yesterday I read an article in a major newspaper (NYT, WSJ, or washington post - sorry, couldn't find link) describing how many high tech things (including the ipod) didn't come with suitable warranties -- for example, dell just changed from a 3 year to 1 year warranty.
Since Nvidia doesn't have a license to develop for the intel bus, this will interface to AMD processors (uh, despite that the xbox is intel-based). A version for the Hammer is "far along" and may merge north and south bridge functions into one chip.
Four Taiwanese motherboard manufacturers, including Asus and Chaintech, will use the chips
A future version for server line cards may include gigabit ethernet, routing capability, and a HyperTransport link to network processors.
No, neither of you are scientists. Hydrogen is more powerful. Jusy kidding; I'm sure you both knew this already.
There's the old high school experiment: the teacher pops an H-filled balloon with a candle and there's a bang. Then they pop a balloon filled with 2:1 O:H molecule ratio, and repeat the test - an earth shattering kaboom. The trick is to make sure that the 2 elements to burn are well mixed -- that's why dynamite (whose molecules include ready-to-react oxygen) is so much more effective than gunpowder (which is coarsely mixed with oxygen). Heck, even flour is explosive when mixed with the right proportion of air in a silo
I think
Small children: Trojans
is much more appropriate.
I had a friend who was constantly (once per hour) checking the progress of his package via Fedex. So, I mirrored the Fedex website and changed the "hosts" file of a lab computer to point to my mirror's IP. Imagine his surprise when he logs into the *correct* website, types in his tracking number, and finds that the package was last checked into a flooded sorting facility and it should take a week for them to pump out all the water and dry out the packages!
Hi -- I put it up in this post
finally got it uploaded; sorry for the delay
I wish someone would make something like this for the car. There are multi-disc changers, but they hold, at most, 10 cds and are often mounted in the trunk. I'd love the versatility of a large range of music, without...
- having to juggle which cds are in my car and are in my house
- the mess of many cds sitting around in the car
- not being able to play a cd because it wouldn't be safe drive while trying to find it
- the chance that my cds will be stolen/damaged
MP3 cd players are nice, but I still have to select a playlist and keep the cd up-to-date with my favorites.
Thanks everyone...
Here's the video (2.8 MB). It should take about 10 more minutes to ftp up. There is no soundtrack, so I'll give the narration here:
The satellite is called GEMstar and was designed to provide SMS-like messaging all over the world. It was built circa 1994-5 and was lost when the rocket blew up. That didn't stop me from producing the video of what it would have looked like!
The video shows a couple of stages that occur when the satellite is released from the rocket. First, it initially tumbles. Then the solar panels deploy (like everything else, they had to be squeezed in to fit in the nosecone of the rocket). The attitude control system (ACS) turns on and stabalizes the spin of the satellite so that it faces towards the earth. This is done with momentum wheels (heavy wheels inside the satellite) and torq coils (coils that act against the earth's magnetic field). Next, the main helicial antenna is deployed, and it's ready for service!
A few notes on the parts of the satellite. The blue panels are solar cells. The gold ring at the bottom is the seperation ring that attaches the whole thing to the rocket. The 4 white squares on top are GPS antennas connected to a special receiver that can measure the phase difference between the antennas and therefore figure out (not only x,y,z and time) its pitch, roll, and yaw. The X-shaped thing on the top of the satellite is a gravity gradient boom. Deployment of this probably should have been in the video, but oh well. It pops out maybe 10 feet and, due to some simple physics I don't understand, will help orient the satellite so that it faces the earth. (In reality, the satellite isn't staying still, it has to constantly re-aim to keep pointing at the earth). On the side panel, the little circle is a window for the earth sensor. There is another one on the other side, and they help orient the satellite.
Antennas- The 4 blade antennas are for command & control. These form a broad pattern and are useful to talk to the satelite when the main antennas aren't pointed correctly (like when there is a problem). Being a broader pattern, they require more power.
The boom antenna has two elements - a larger 150 Mhz antenna to receive transmissions from ground users (who transmit on less licensed taxicab-like frequencies), and a smaller ~400 MHz transmit antenna at the tip. This antenna was the hardest part of the animation because there were no 'spiral' primitives in POVray. I ended up writing a little program in C to generate a bunch of triangle strips, and then used 4 copies of this (at 90, 180, and 270 degrees). The deployment is totally bogus - I just scaled the structure, when in reality the width of the strips don't change.
True story: our competitor at the time was Orbital with their series of ORBcomm satellites. They used a similar antenna structure, but theirs folded up sideways, like a staw that has been rolled up. Our antenna was made of metal, plastic, and fiberglass - theirs was made of copper tape, kapton (a space-rated scotch tape), and bamboo. I never thought that anyone would fly a wooden satellite!
Check out this summary of an ipod teardown - pretty pictures! Or you can order the full 60 page report for $1950
Thanks everyone for the suggestions!
I found that ppmtompeg already installed with my RedHat distribution. I found my old pictures off of my backup CD (which was taken from my backup SyQuest EZ-Drive 135) - it turns out that there were 500 frames @ 640x480, so it's 15 seconds of FULL SCREEN bliss! I got it all set up, wrote the parameter file, and then.... nothing. I ran it with strace- it parses the parameter file correctly, but then it doesn't even attempt open up my first frame. Thanks again; now I've got lots more options to try!
It was Defense Systems, Inc, which was bought out by CTA and renamed CTA Space Systems, which was bought out by Orbital (aka OSC).
I worked at a company building a small satellite. For fun in my few off hours, I did a POVray animation illustrating the various stages of deployment - the solar cells deploy, then the first antenna, then the second, etc. I did a small animation on my 100MHz 486 laptop and management commissioned a high quality large animation to be done in 4 days.
I rigged up 13 unsuspecting computers at the office - just about our entire inventory of brand new P90's. Imagine - over a Gigahertz of processing power at my disposal! Luckily, I had been dabbling in multiprocessing and wrote a simple client and server software to manage it all. Each frame took about 30 minute to render, and the whole thing was done in about 12 hours (300 frames=10 seconds of video).
The file size was huge - 300 frames of 800x600 uncompressed TGA's = 412 MB. We only had an internal network, so we couldn't use the internet to send it. Luckily, I had just bought a new laptop with a still-mostly-empty 800 MB hard drive. I used a parallel cable to transfer the files onto the drive (If I didn't, I would have filled the network drive), and when I got to the place that was going to transfer the images to video tape, I used laplink again to put the data on their machine (filling their drive, too!).
Eventually, I'd like to make an mpeg of it so I can show friends. Any suggestions for a free encoder?
We had a room-sized temperature chamber for baking/freezing satellites that used water cooling. When we'd fire it up, we rolled out a fire hose (literally!) into the parking lot, so that it could drain into the sewer. Technically it's not legal to put treated water into the storm sewer system (it's for rainwater, not chlorinated water), so we were quick to roll it back up.
I'd recommend this book: High Performance Computing. It covers this trick and many others -- if your compiler doesn't do them automatically, then you can hand code it.
Actually, that's not the issue. The issue is who owns the keys.
In the the first case, the user has control of the crypto keys and uses it to determine what data to accept into his or her computer, use it to make sure outgoing data securely makes it to its intended destination.
In the second case, the keys are held by the manufacturer of the hardware and the operating system. They determine how a user's computer can be used.
Being forced to use encryption/authentication is not a problem at all; just as long as I can control what things I think are acceptable. I use linux and my files have different levels of access - user, group, superuser - but, as long as I have root on my computer (and no one else does), file access restrictions are a security great benefit to me.