Baja 1000

Beau Schwabe

I just thought I would throw this out to see what kind of ideas it would generate.
·
I ran into a guy this evening at a birthday party that my daughter had been invited to·that races in the Baja 1000 every year.· Anyway, one of the things that he wants to do is equip his vehicle with 24/7 video capabilities throughout the entire race.· One of the big problems is finding a video camera capable of surviving up to 5g's throughout the journey.·· ...Similar to what 'micron' is doing, only he doesn't have a big sponsor like Micron so he can't shell out the $$ for the image sensors they are using... (http://www.micron.com/baja1000/) Another issue is storage space for that much video...· Typically it takes his team 32 hours to run the race. (<--Teams are given 40 hours to complete the race)· The camera should also be sensitive to night video with a light source only from the vehicles headlights.
·
At this point what I would like to get a better grasp on is what kind of video options are out there capable of capturing a continuous 115,200 seconds and able to withstand·up to 5g's.·
·
Obvious other things along the way would be to include GPS, Speed, Engine RPM, accelerometer data, etc. either superimposed on the video, or recorded separately with a synchronous time stamp.
·

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Beau Schwabe

IC Layout Engineer
Parallax, Inc.

RGuyser

having dropped eggs off buildings in milk cartons stuffed with foam and stuff, i bet a camera mount can be made without too much over thinking... for storage.. i dunno. it seems like solidstate would be tempting... but 32 hours... wow.. that needs to be quite a few 4gb USB memory cards!

a single board computer booting off solid state memory(ive heard of a 90mb winxp that can boot off flash drives) and a bunch of 4-8gb USB thumb drives?

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3D & 2D Design - Technical Documentation
www.robertguyser.com

Beau Schwabe

RGuyser,

Yeah, that's about what I told him. He did mention that he would be willing to sacrifice video resolution just to get a complete video of the race from the car's perspective... but still.

Even at 176x144 NTSC if you use 8-bit color resolution that's 203k per frame...Assuming 30fps that's 6.1Megs per second x 115,200 seconds = 703 Gigs!

I was hoping for a video compression solution.

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Beau Schwabe

IC Layout Engineer
Parallax, Inc.

Desy2820

Just thinking out loud, but by any chance does your friend have his HAM license?· Or do you someone who does?· This sounds like a perfect application for Amateur TV (ATV).· Camera and transmitter in the race car, with a receiver and VCRs in the support/chase car.· Just need someone to keep swapping the tapes!· Almost forgot, use an overlay module (and Parallax micro)·for the real-time data, such as elapsed time, position, etc.

The hard part might be finding a heavy-duty camera and transmitter.

Trying to help!




Post Edited (Desy2820) : 2/12/2007 10:14:39 AM GMT

Beau Schwabe

Desy2820,

I thought about transmitting the video, but because of the distances involved and the obstacles on the track there is no way that a chase vehicle would be able to stay within range.

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Beau Schwabe

IC Layout Engineer
Parallax, Inc.

John R.

Unless...

You got a "co-op" of a number of participants together, and possibly some HAM Radio groups, and found a way to set up a system of "repeaters".

This could be an interesting project for one of the national/international groups like ARL or MARS or someone like that. I'm not a "HAM" but I've known some, and given the right group of guys, and rigth circumstances, they'd eat this up.

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John R.
Click here to see my Nomad Build Log

steve_b

If you start giving up resolution, you'll immediately regret it when reviewing it.

Why go 30fps? IF it's good enough quality, why not go with 15fps.... Or less.
During daylight, a series of still pictures would probably be fine. But auto-exposure for night time pictures means the shutter is left open longer and you'd end up with a blurred image (light streaks).

Hasn't someone in the propellor area hooked up a CCD yet? Then just write to a few large flash drives? hehe..sorry to trivialize it.

Whatever you create....right it off! These guys wipeout and then push the car back on it's wheels and keep going...so anything you mount will probably be gone!! hehe

Go with either a flashbased camcorder with shockmounts or an old digital camera taking timed stills. Have a single board computer connected to it to download the images to a flash drive. I think the best you could do with timed stills is 1fps (using preset focus settings).
Some digital camera's have movie modes that only run at 15fps. (I just got an Olympus 720SW that is shockproof wrt a 5ft drop...not sure how that equates to G-forces..but I'd think more than 5 with it's weight and all).

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·

Steve

"Inside each and every one of us is our one, true authentic swing. Something we was born with. Something that's ours and ours alone. Something that can't be learned... something that's got to be remembered."

RGuyser

Beau Schwabe (Parallax) said...
RGuyser,

Yeah, that's about what I told him. He did mention that he would be willing to sacrifice video resolution just to get a complete video of the race from the car's perspective... but still.

Even at 176x144 NTSC if you use 8-bit color resolution that's 203k per frame...Assuming 30fps that's 6.1Megs per second x 115,200 seconds = 703 Gigs!

I was hoping for a video compression solution.

I think you can do better than that. a e hour divx at surprisingly good resolution is about 900mb - that is more like 30-40gb. this is easier t accept. another idea could be to didassemble an oldish laptop(1ghz range), put a beefy hdd in it, wrap it in foam, and put it in a padded attache case.... glue all the connectors...

clearly i havent got usefull suggstions and wil stop now!

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3D & 2D Design - Technical Documentation
www.robertguyser.com

Phil Pilgrim (PhiPi)

You might consider one of the Axis webcams. These can output streaming video via ethernet, and they do MJPEG compression on the fly. The old Axis 2100 I have produces good picture quality. I'm sure some of their newer offerings are even better.

-Phil

Robert Kubichek

Phil Pilgrim (PhiPi) said...
You might consider one of the Axis webcams. These can output streaming video via ethernet, and they do MJPEG compression on the fly. The old Axis 2100 I have produces good picture quality. I'm sure some of their newer offerings are even better.

-Phil

Yup, and with a good AP and a high power amp, and several pre positioned recievers, you could do it...

BTW, the laptop hard drive route might work, but you will have to be darned sure you mount the hard drive
in a suitable shock proof enclosure...

I would personaly use a micro-nano-atx mob with 1 gig memory,
and a 120W pico-power supply in a custom case...

That way you can use off the shelf components (vid capture card/ laptop hd),
OR sollid state memory sticks that are as large as 32GIG USB2 (not cheap)
but reliable shockproof, and LOW power...
www.windowsmarketplace.com/details.aspx?view=info&itemid=2632063

It just depends on the amount of storage you need..

Here is a link to video capturedevice evaluations ect.
www.videoguys.com/vidcap.htm

Bob

Phil Pilgrim (PhiPi)

I was thinking more along the lines of streaming the webcam video via CAT5 to one of those Buffalo LinkStation NAS drives, carried onboard the vehicle. No wireless needed. The Buffalos come with large-capacity disks, and they run Linux; so they could be programmed to capture and store the video on the fly.

-Phil

Robert Kubichek

Phil Pilgrim (PhiPi) said...
I was thinking more along the lines of streaming the webcam video via CAT5 to one of those Buffalo LinkStation NAS drives, carried onboard the vehicle. No wireless needed. The Buffalos come with large-capacity disks, and they run Linux; so they could be programmed to capture and store the video on the fly.

-Phil

The problem with it, is that it will not withstand the G-Forces encountered during the Baja race...
Your best bet is a small form factor mob with passive cooling, and solid state storage...
It will have a ethernet port as well, and is easier to configure softwarewise....
Your main cost will be RELIABLE storage....
A laptop HD just will not withstand the G-forces encountered reliably..
Flash drives will, and also use less power, and you can connect more than one drive to the mob
for increased storeage capacity...
You need to figure out how good of a quality you want to record video versus how much storage
you will have/get, and go from there...

Bob

Post Edited (Robert Kubichek) : 2/12/2007 8:25:09 PM GMT

Lawson

On the video compression front.· First off, the camera, this is kind of obvous but camera quality WILL effect how well a video stream compresses.· Any noise in the video from the camera will degrade the quality of the final compressed video and force the use of·a higher bit-rate.··As an experiment try compressing video from a TV·antenna or cheap cam-corder and compare it with video sourced from a DVD and converted to the same resolution and frame-rate before finally compressing it at the same settings.·

Next compression codecs.· listed from worst compression ratio to best compression ratio.· Huffyuv(lossless), MJPG, MPEG-1, MPEG-2 (DVD's and HDTV), MPEG-4 (Divix, Xvid), H.264.·· RealVideo, MicrosoftVideo, and Quicktime all fall into this range but are non-standard and don't produce better results anyway.· The above list is also ranked in terms of computer horsepower needed.· With MJPG being the easiest, and H.264 being the hardest.· Infact I think only top of the line CPUs (or dedicated hardware) can do H.264 in realtime.· (personally i'd go with MPEG-4 Xvid if the system is fast enough)· Whatever compression codec is finally chosen, be SHURE to extensively test the compression and play with all the settings given.· Oh yea, going with 15fps video can save some space with MPEG compression but it's only like 10% and can make high-motion video look crappy.· (dropping the resolution gives similar small gains in compression so while it can help don't go wild)·

A bonus if you go with MPEG-2 compression is that a large number of TV-capture cards now do·MPEG-2 in hardware, this makes the overall system MUCH more stable and lets the CPU do other stuff (like play games!).· If you do decide to use a TV-capture card I'd recommend going with a Hauppauge product.· http://www.hauppauge.com/·My only reason for recommending a Hauppauge card is that they·seem to be supported by the most 3rd party Open-Source software packages.·

http://www.virtualdub.com/· VirtualDub is the program I primarily use to convert video files from one format to another.· It also has a superb video capture system builtin.· This system provides rock solid audio/video sync and will automatically split up the output file into managable chunks.· Although the capture system in VirtualDub is now out·of date thanks to microsoft.· ·(it was built in the Win98 days)

Finally, storage.· 5G shock isn't that harsh.· (I think hard drives are spec'ed to 10g or 20g operating shocks don't trust me though, read the data-sheets) ·I wouldn't be supprised if a well shockmounted RAID-5 array with a few hot-spares could survive the trip just fine.·(the heat would likely be the worst part of the trip)·WinXP pro· can do software RAID-5 arrays (ofc Linux can do this too) and big hard-drives are cheap now so this plan could allow 1-2Tbytes of data storage.·

http://www.avsforum.com/·is the best Web-forum I've found for video related info.· Lots of people on that forum will be up to date on this stuff.

My 2¢,

Marty Lawson

Phil Pilgrim (PhiPi)

Bob,

Anything can be shock-mounted against short-duration jolts. It's not like the G forces will be sustained, as they would be in a fighter jet. That aside, though, the bigger issue with the Buffalo unit is likely to be its fan cooling versus the Baja dust. Another solution, more along the lines you mention, is the LinkSys NSLU2 NAS unit. This is a diskless device with two USB 2.0 ports that could be used for flash memory sticks. But I'm wondering if flash memory has a fast enough write speed to accommodate real-time video. The Sony MemoryStick, for example, comes in two flavors: regular and Pro. Only the Pro version is fast enough to capture extended video using a Sony digicam. I doubt that most USB pen drives are up to that level of write performance.

-Phil

Lawson

I also forgot to mention http://www.grc.com/sr/spinrite.htm If you do use hard-drives this program is likely to be able to fix or recover from HD failures that occur (shock shouldn't kill the controller of the HD, but is bad for the recording surface)

little bit 2. CompactFlash type memory cards act exactly like ATA hard drives. (fully bootable, no need for OS support, just need a plug adaptor) I've seen some models quoted at 40MByte/s read/write speeds but this app won't need anywhere near that.

I don't think write speed will be an issue with Flash memory. 1Mbit/s MPEG-4 video looks dang sharp at TV resolutions and even cheap usb flash drives should be able to manage that speed.

another tidbit u might find usefull. My TV card has a hardware MPEG-2 encoder so it can record while i'm doing ANYTHING else. (CPU use is ~5% during recording, the only way i know it's recording is 'cause the HD light is constantly blinking) At 640x480 ~30fps with 32KHz compressed audio and a data rate of ~4.4Mbits/s total, compression artifacts are hardly visable (an "average" TV signal was the source, the stuff I could see was mostly from the source noise). That comes out to a little less than 2GBytes an hour or 80GBytes for 40 hours of video. At ~2.2Mbits/s with the same fram size, frame rate and a bit more audio compression video quality is still very high, compression artifacts are visable, but not a problem yet.

My 2¢,
Marty

steve_b

As far as heat goes....a couple of peltier elements will be fine in an enclosed box.
At work we have a receiver (for RF) tucked in what is basically a beer fridge. Lots of heat in dat'der'box. So there's a copper fin plate in the lid that has fans on both sides (in and out) to move air across it.

A pelletier with the cool side touching the outside of a metal box will do alright. On the inside have a pc fan/sink moving air across the cool spot!

As far as g's....sustained G's wouldn't be near 5g's....but sometimes these things are rated on certain angles. A flat drop as opposed to a corner drop...
Anyhow, if anything comes loose it'll certainly generated more than 5g's.
Something shock mounted and dampened would work fine!

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·

Steve

"Inside each and every one of us is our one, true authentic swing. Something we was born with. Something that's ours and ours alone. Something that can't be learned... something that's got to be remembered."

Beau Schwabe

Thanks for all of your input!

I will see what this guy wants to do, I at least have a few more ideas/options now that I can suggest the why vs. the why not.

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Beau Schwabe

IC Layout Engineer
Parallax, Inc.

kelvin james

Another opinion to throw in here. For the type of usable quality and issues of low light and image stabilization, a prosumer cam would be required, most likely minidv. As far as the image stabilization goes, anyone that has used a video cam knows what even hand shake can do, let alone 5G, even on a shock mount. If this is not addressed properly, then a major portion of the video would be basically useless from the shake in the frames. For 32 hours on dv would be approx. 4 terabytes, so recording to hard disk would be an issue. You could go down to 24p, but still won't save a lot. I would look at the obvious, find a fast and reliable way for the copilot to change the tapes. Changing tapes in the camera itself would be too distracting and akward depending on where it is mounted. It "may" be possible to record straight to a minidv deck mounted in the front of the car, from the cam. A visual timer could be rigged up to let the copilot know when a tape change is needed, thus being prepared in advance. Pretty simple, eject the tape, throw in a new one, hit record, and way you go for another hour. They will miss a little bit of footage during the change, but over 32 hours, i don't think that is a big deal.

kelvin

Eric R

Beau,

PC104 might be an option. They are industrial, small and offer frame grabbers and memory storage.

Have you looked at M-Systems for storage?

http://www.m-systems.com/NR/rdonlyres/DF55B3A3-E128-4666-B894-48D48E031019/0/DOC2000_DIP_DS_Rev39.pdf%7CDOC_2000_DIP_DS_Rev3.8.pdf

Looks like they have a 1 gig solution.



PC104 frame grabber card here that looks like it might work.

http://www.sensoray.com/products/311data.htm

Zoot

What about using a consumer DVR (digital video recorder) hooked up to a consumer video camera? If an 80-hour Tivo can be had for < $200 it seems like this should be doable, and then the issue becomes shock-mounting, which again, shouldn't be too difficult. 5gs may seem like a lot, but I've abused all kinds of laptops, harddrives, etc., out in the desert doing off-road photography and videography with no shock protection at all and have not had problems. So if you did have shock protection on the DVR it would probably work OK. At that kind of price (maybe get some DVRs on ebay?) you would have two or three of them all recording at once so if one fails, you'd have some redundancy.

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When the going gets weird, the weird turn pro. -- HST

Beau Schwabe

Zoot,

I like the idea of a Tivo and a video camera as well as having redundancy, but there is some harsh terrain that may limit the "amount" of heavy/bulky equipment
placed on the vehicle. For example there was a part of the race last year that had this guy going through a mud puddle waist deep. I have some experience
with shock-mounting and video stabilization using gyro-s (I once fit an ultra-light aircraft for some aerial photography), but due to the circumstances it becomes
a matter of how compact and weather proof the unit can be made. The Tivo would just need to be shock proofed, while the camera needs both shock and
image stability.

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Beau Schwabe

IC Layout Engineer
Parallax, Inc.

Lawson

I remember a lot of the DARPA grand challenge competitors using either a rigid camera mount or a gyro stabilized turret. I think that aside from engine/drive vibration a car's chassis is pretty stable. (the natural frequency of a car suspension is in the 1Hz range with 2000lb or more for inertia. It's hard to improve on isolation like that with a light/compact passive isolator. ofc active isolation is a different story.)

Heh, just because the Tivo started out bulky doesn't mean it has to stay that way [noparse]:)[/noparse]. Stripped down to the electronics with a new powersupply, case, cooling, and front panel buttons I wouldn't be supprised if a pair of Tivo's could fit in less space than a single stock unit.

Marty

Robert Kubichek

Right, and you can always increase the storage by putting in larger drives..

Bob

Zoot

I used the Tivo as an example because they clearly have the recording time are not expensive. The only thing I can't speak to is can you record if you are not hooked up to the Tivo service (Tivos use a phoneline/broadband to communicate with Tivo central -- to what end, I don't know).

There are LOTS of DVRs out there -- I went poking around. Priced $150-$3000 depending on features, cameras, etc. Many offer over 40 hour record time.

Here's one I found on Ebay that records full DVR (Divx or MPEG4 compression, 30fps, 720x480) and it's portable -- which means small and probably a bit durable:

cgi.ebay.com/ARCHOS-AV500-30GB-MULTIMEDIA-PLAYER-DVR-4-IN-LCD-SCREEN_W0QQitemZ130079926469QQihZ003QQcategoryZ48682QQrdZ1QQcmdZViewItem
This bidding ends in an hour, so not sure it will still be there if you go look but here's link to lots and lots 'em at ebay:

electronics.search.ebay.com/dvr_Consumer-Electronics_W0QQfkrZ1QQfromZR8QQsacatZ293QQsubmitsearchZSearch

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When the going gets weird, the weird turn pro. -- HST

OzStamp

Hi Beau

Consider having a quick peeky boo here.Two links below

http://www.helmetcamera.com/

http://www.helmetcamera.com.au/home.htm

A std video camera or a device like a Trivio( and others ) do a pretty good job

A guy I know has a Helmetcam .. he is a crack rider .. mono's up steep hills and on extremely
roug and rocky terrain .. we go for hours and hours .. uses tapes and a few small batteries.


Ronald Nollet·· OZ··
·

Beau Schwabe

Lawson,

"I think that aside from engine/drive vibration a car's chassis is pretty stable."

Thanks, your right something secured to the car might not be as thrown around as the driver would be.


Zoot,

"Tivos use a phone line/broadband to communicate with Tivo central -- to what end, I don't know"

Hmmm... surly there is a way to defeat this... what if you are a customer in a remote area without phone
service and you want to Tivo something off of satellite. (Obviously I am behind the times and don't have
a Tivo box)


Wow, The DVR "Really" looks like the way to go.

The ARCHOS AV500 30GB MULTIMEDIA PLAYER has an impressive boast under its Product Features:
"Plays and stores up to 400 hours of video, 250 movies, 55,000 songs or 1,000,000 photos"

Looks like this is a regular E-Bay Item ... Right now, there is one going for under $100

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Beau Schwabe

IC Layout Engineer
Parallax, Inc.

Zoot

I don't Tivo either -- I only thought of it because I know it's a DVR inside and they're not very pricey. My guess is that the 'net connection is for hooking up to a TV schedule and to get around recording blocks on digital cable converters.

In any case, as you've seen, there are lots of plain DVRs out there that are not much different than a regular old time VCR.

Those helmet cams are cool -- their recorders look limited to 4 hours or so, though. The idea of recording to SD cards rather than a hard drive is neat, though.

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When the going gets weird, the weird turn pro. -- HST

Superworms

actully, the phone jack on hte back of the tivo is for softwere updates, show listings etc.

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Equipped with his 5 senses, man explores the world around and calls his adventure science
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-Edwin Hubble
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Tom Walker

To expand on what superworms said, the economical model that the tivo-type market is based on is that the unit must sync up with its service (tivo, RePlay, etc...) every day or two, to receive update program listings (for you to choose from to record), to update software and to verify that your subscription with their service is up to date. If it not, your unit will no longer record. This "check-in" is usually done via a phone connection (typically during the late-night hours), but the newer units will also allow an internet connection to perform the same function. An advantage to the "network-type" connection is that units on the same service can "share" with each other...either within your own house (great for recording something on one unit in the living room and then watching it on the unit in your den later) or with "trusted" units anywhere (at least this is true with the RePlay service). Sharing from within your house is basically "playing through the network line" while programs from "trusted" units actually transfer to your unit via your broadband connection.

I have not seen any units that don't require a subscription to some service, so I can't comment on how they work.

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Truly Understand the Fundamentals and the Path will be so much easier...