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Creating A Tiny, Free, Roaming Webcam?
"I thought it would be cool to mount a webcam on my bike when I go this July. I looked around on the web and the only similar implementations I could find included a bike trailer and 20lbs worth of computer parts. I know that a person can do better than that. I'll be at least 5 miles from a support van at any time so short range solutions (Bluetooth, 2.4ghz wireless LAN) isn't an option unfortunately. What I'm looking into is a small webcam linked to a PDA with a cellular modem. The webcam takes pictures every couple of minutes and the PDA takes the image, calls on the cell modem, uploads the pic, and disconnects the call. This saves me cellular charges and conserves power so that I don't have to carry a bunch of batteries with me.
Basically I've gotten to the point that I need a firm set of hardware and a good wireless implementation to get the information to the servers. Below is what I will need for the system. Any suggestions for each piece, or a full working system that could be purchased would be very helpful.
Webcam: the smaller and more power efficient the better, something all weather, the size and shape of a pen would be optimal since aerodynamics play a part in this piece and I don't want something like a Logitech QuickCam stuck to my helmet.
Computer: PDA sized or smaller if possible. Needs to be able to connect to both a Webcam and a Cellular Modem and be able to do the work explained above. As power efficient as possible, the longest lasting batteries possible. Needs to fit in bicycling jersey pocket (about 4 inches wide and 8 inches deep).
Modem: this is problematic as not all of Iowa is covered for digital cellular service but all of Iowa IS covered for analog at least. Another option may be the recently reinstated Iridium system (I read somewhere they allowed data transfers)."
You should look into PC/104 and other miniaturized PC systems for this. All you'll end up needing is USB support for a D-Link camera, and PCMCIA for your modem (only 1 type II if you use the Merlin or Sierra AirCard).
That's only two modules, perhaps just one. There may be other solutions as well that you can look into. Since you don't seem to need video output as well for this, a serial console would be ideal, and you wouldn't need it to be hooked up all the time anyway.
Finally, the disconnect for CDPD will only be needed to save battery power. Most service plans are unlimited service, not per kilobyte, unless you're roaming.
Here's your USB cam:
http://www.dlink.com/products/usb/dsbc300/
With proper mounting (think about shockmounting and using a flash chip for storage, it'll be a lot more durable) on the bike frame, the profile will be fairly small.
For even more insanity, you can use an ultralight subnote like a Libretto (with a USB card) or a VAIO PictureBook, depending on OS support. This would be easier to get on short notice, of course, but you'd need someone to supply you with batteries.
Best of luck!
Raptor
Raptor
"Procrastination is great. It gives me a lot more time to do things that I'm never going to do."
(Damn, she just took the cam out of her pants!!)
Sean
I'm working on something vaguely similar to this as part of my Embedded Linux Challenge entry...
Using a PC-104 device, supplied by ELJ, I'm making use of two radio transceivers... They have a data rate of 56k (though I believe you can purchace higher-data-rate modules) and range of, get this, 40 km, line-of-sight. We're currently doing testing to ascertain the range without line-of-sight in various situations (city, suburbs, woods, etc) so I can't comment on how well they do, though 5 miles should be plenty close to maintain the full data rate...
They can connect using a "developers'" board that contains an RS-232 chip, and some status LEDs... quite cool, all told. They run on 5-12 VDC, so batteries are certainly an option.
They're made by World Wireless Communications. IIRC, they cost us something like $400/piece. Look into 'em.
TheNewWazoo
First, perhaps instead of making use of the batteries exclusively, you could hook a generator to the bike. The generator could be used to charge the batteries where you have 2 sets and you alternate between charge and use/expend.
Secondly, I would refer you to all of the embedded linux solutions: check out:
http://www.linux-embedded.com/
A lot of manufacturers make PC compatible single board computers (some very small) that will run Linux. The Basic STAMP micro-controllers might not be a bad choice either, they come with a lot of accessories (such as a mini-webserver) and a lot of hobbyist work with them: check out:
http://www.parallaxinc.com/
Lastly, I would refer you to Information Unlimited at:
http://www.amazing1.com
to get a small, low cost CCD camera, assuming that you didn't want to go with one of the cheapy webcams out there.
As you might be able to surmise, I have given thought to the kind of project you describe (hobbyist robotics actually). I don't really have THE answer for you, but these are some good places to look. I hope this helps.
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http://navasgrp.home.att.net/tech/sch-8500/
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http://www.interpug.com/npug/articles/sprint2.htm
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http://store.yahoo.com/cellularaccessorycom/datca
b samsch.html
A samsung sprint pcs modem has a serial port and is a modem; just put a modem where you want to connect to (or use a more costly ISP) and dial up. Then transfer the file and disconnect. The samsung 8500 has a special serial cable just for hooking directly up to a palm V. no costly PDA modem needed. This is also largly true of GSM modems (the omnipoint ones here, like that nokia dual band thing).I was told once, and I now think it a lie, that GSM worked by communicating to low orbit satellites and hence was global. I don't know if that's true, but I'd hope that either sprint pcs, or GSM would be widely available over the entirety of your course.
Don't ask about the camera, I wouldn't really suggest that sony picture book. But the cam for the clie is no longer an option it seems; and things like this never seem to be real. Although the visor eye module may be what you'd want in that case.
Have you ever thought about using a radio modem to a chase vehicle? When I was working on my school's solar car project in 1995, we had a van loaded with various telemetry equiptment, including a radio modem connection to the car, so that we could get speed, battery consumption, etc.
I don't know enough about your race, but with a power inverter, a few space car batteries, and someone willing to follow you in a car, this wouldn't be that hard to pull off.
[If, however, the race route is completely closed off to vehicles, this would be more difficult].
You might also look into other forms of communication. Check to see if Metricom has access in our area, or someone like them. [I haven't had one of their modems since '97, but the modem at that time had a battery which lasted me a good 3-4 hrs of constant use.]
With the chase vehicle concept, you might also try looking at X10 gear, but I don't know what their power consumption is.
Build it, and they will come^Hplain.
- Visor Deluxe or Platinum ($250 / $300, 8MB of memory, runs for about 2-6 weeks off a pair of AA batteries) The Prism would let you look at your pictures in color, but has rechargeable batteries, so probably wouldn't work for you. The greyscale Visors seem to be able to store color pictures, though.
- Eyemodule2 ($200 , you can download the picture emailer program from Palmgear.com or freewarepalm.com there's also the greyscale eyemodule1 for cheaper some places)
- cell phone with a modem (~$170 for my little Nokia phone with IRDA. There are Visorphones ($300) and wireless modules for the Visor, but then you'd have to swap modules all the time. For service, I have Voicestream GSM, but that's limited to 9600baud digital service right now... I think TDMA (AT&T, Verizon) networks might let you connect up to 14400baud and have more complete analog roaming).
- if you want to get fancy, you could spend maybe $100 or so on phone-Visor serial cables so you don't have to hold them together to use the lame IRDA link, so you can keep pedalling while you're connected. Then again, it might be cheaper and more convenient to just duct tape both of them to your handlebars so the IRDA links always work... that way you could use the phone's serial port for a handsfree kit so you can talk to people when you aren't dialed in. A pet peeve of mine with the Nokia phone is that the IRDA port is on the wrong side of the phone, so I have to hold it upside down to use my Visor. But you could probably get creative with a mirror.)
- you might want to program a script (or get someone else to program a script
:) ) to automate the picture grabbing/uploading tasks with one button. I don't think I've seen anything like that yet...
Good luck! Sounds like you're going to have a lot of fun!So here's my specs for a cam setup that could get reasonably interesting pictures:
- Vibrational stability. No use getting jittery, blurred pix, right?
- Aimability. What if the most interesting pic of the moment isn't directly ahead? This might include lens with a moderate amount of wide angle/zoom capability. This could probably be accomplished with a semi-custom tripod head fitting.
- To go with aimability, etc. I would add detachability -- in case the bicyle it is mounted on were damaged, the setup could be moved. Secondarily there are many more interesting pix to be had when the riders aren't actually in motion, and finally
- Reasonably high resolution and color depth, because even if you are transmitting images live, how many people can watch the whole seven day race? So back at the web server end, and after the race is finished, you want to have better than average pix as a result of all the effort.
All of this says that what you probably want on the handlebars is a fairly decent megapixel camera, probably the one that uses an IBM microdrive -- one I have heard of can store 1500 pictures. (Which would be about one a minute for 12 hours), assuming that the cam uses AA batteries, so that a recharger can takes care of the continued power requirements. Nearly all the good digital cams have USB, so you have an easy connection to the device which will be responsible for image collection and transmission.Then we have to consider the other end: transmitting the image without a high speed data link. Since high res, high color pix require major bandwidth, the collector has to be able to compress the incoming images, probably resized for web page formatting, and perhaps tagged so that the high res pix from the camera can later be uploaded and replace the lower res image or be available from a thumbnail.
Probably requires more than a PDA. So my vote goes to the smallest Transmeta-powered device capable of the image processing, equipped with a wireless PC-MIA modem of some type. (Clueless about the best communication option here, fellow /.'ers, help me out!) Finally, I would think that a person would need a small solar panel to keep all of the devices and batteries charged, so the Transmeta device would rest just under the solar panel probably on a cushioned rack above the back wheel.
Still weighs alot less than 20 lbs, I would think, and positioned properly shouldn't add that much drag. Best I can do but fellow readers, what do you think?
...Open Source isn't the only answer -- but it's almost always a better value than the alternatives...
My wireless Web setup is:
This stuff allows me to browse the web wirelessly. I'm not actually sure how you'd upload starting with this setup; I suspect that's a software problem, and I'm hoping it's solved elsewhere in this thread.
That said, I'll throw out some other notes on systems like this. First, they are flaky, and don't like you moving, so when you get a connection, stop moving. A modem connection seems to be much more fragile when switching between network cells than a phone call is. Second, think redundant. Get multiple paths of connection, because there are so many places where the connection can break down, and you'll go crazy if you absolutely depend on any of them. Lastly, forget about sending up pictures and enjoy the ride. Experiences like that aren't for sharing with other people over the web, they are for experiencing first hand, while it's going on. The 3rd California AIDS Ride from San Francisco to Los Angeles changed my life, but it wouldn't have if I'd been fretting over hardware the whole time.
mahlen
See how today's achievement is only tomorrow's confusion; see how possession always cheapens the thing that was precious. --William Dean Howells (1837-1920)
"Ham" (amateur) radio groups provide communications support for the ride. This may include ATV (amateur television) and definietly includes APRS (amatuer position reporting system). ATV can send live NTSC-quality video and audio at least from near cities on the route. APRS has an add-on protocol for sending still images and supports links to internet feeds. The hams have already figured out solutions to power, equipment, safety, and operating procedures.
Another approach might be to use a CPDP modem with a laptop. I do not think there is an easy way to do it with a Palm or Visor, although there is a simple httpd server for the palm that works fine with the omnisky modem. Coverage outside of cities may be a problem.