Visual Field Augmentation
2nd Generation Device - Introducing the Virtual Vision Sport Display
Before beginning the next phase, an issue was raised concerning, the use of a 7805 Voltage regulator to derive a clean 5VDC source for the ViewFinder. The 7805 is an inefficient device in that the way that it regulates leads to a significant current draw beyond what is required by the load device.
Generally in a commercial application where house hold ac voltage is the primary source, cost and heat sinking are weighed as factors in it's use. In this application though the goal will be to ultimately have a battery powered device, and efficiency will only become more important as run times will typically be several hours.
Professor Steve Mann no less, pointed out the issue and drew my attention to a replacement device that would accomplish what the 7805 was intended for while providing an economy of Amperes... I do have to say that I'm more than pleased to have a resource such as Steve watching over this project... below is a link to the power regulation solution that he used in his "Wear Comp" system...
http://www.wearcam.org/wearhow/node11.html
If the "wearcomp" project has peaked your interest, the following link will take you to the "Text Book" used in Mann's Electronics Engineering courses at University of Toronto... (I've ordered mine, and will wait patiently for it to arrive from Chapters.ca)
http://wearcam.org/textbook.htm
The heart of
the VFA Gen 2 (hopefully) will be the unit pictured to the right. The Virtual
Vision Sport, a head mounted Television set that was in production in the early
1990's. This unit was manufactured in 1992, though I just purchased it in Jan of
2003.
After looking at numerous new devices ranging from $699 to $6,000 + USD, the price was far more than I'm in a position to spend on yet another project, especially something as speculative as this.
The unit was located in Monck's Corners Georgia, and purchased for approx $250.00 Canadian. The VV Sport was issued in 2 (two) models, one for Left eye dominant individuals, and the other for right eye dominant individuals.
Even though I'm right eye dominant, and this unit is left eye dominant, I still purchased it as I simply couldn't find any other used unit's after more than 2 weeks of intense searching... The only other option is an I-Scape unit from IO-Display Systems (This would be a Gen4 or Gen5 purchase).
http://www.i-glassesstore.com/iscape.html
It should be noted that the I-Scape incorporates 2 (two) 180K Pixel LCD panels.
An issue with the VV Sport surfaced when I began testing it to determine what condition it was in upon receiving it... Defective... Beyond getting screwed on a shipping credit that went back to the vendor, it didn't work... as the unit is over 10 years old and cost approx $800 USD when new, the belly aching can be kept to a minimum (though likely will resurface over and over again)...
The Eyewear cable that ties the display to the TV tuner was damaged and worked only intermittently... I can see where a lesser person would simply want to dump this unit... as the connector is a sub miniature 9-pin and looks like a nightmare to have to solder.
As it turns out
this misfortune turned to my benefit in that I was forced to scope out the lines
from the tuner assy... during that exercise I determined that as I'm not big on
television, the tuner could be pitched, and now that I have all the relevant
signals the entire base is redundant.
To the left is an image of yours truly looking rather intense and futuristic, beyond looking better than the VFA1 and wearable, it has a long way to go, but I'll bet people remember you.
It is quite comfortable for the brief periods that I have been trying it.
The unit functions by displaying the image on a miniature LCD panel the is mounted in the top of the head piece facing down ward, and measures approx 5/8th of inch across and is back lit.
From what bursts of video that I did see the LCD appears to be functional in so far as there were no dead or stuck-on elements. Individual pixels are known to fail, but entire rows or columns would render this useless.
The prism that focuses the image onto the eye has a clip assembly that fits to the visor.
In use it does in fact act as the literature describes an image that floats in front of you, seemingly 5 or 6 feet away.
Once I interface the camera to it, I intend to obscure any light coming in through the visor, to get better image focus and stability.
This is the test jig I set-up to determine the pin-outs for the Eyewear interface. A cheap NTSC capable digital camera feeds a video signal to the base, as there's no signal out here in the boonies to get an image.
The audio is a mute point for this phase of testing, though I'll keep the ear pieces handy for future purposes.
This
pinout is accurate to the best of my knowledge and I did check it at least three
times, the pin numbering is arbitrary, and should not be considered a reference
if you have a schematic. Though if you have a schematic I would be eternally
grateful for a scanned copy of it...
Similarly any one with a flakey "Right Eye" unit please contact me as that's my next quest after selecting an appropriate micro colour camera. Given the non-functional state of this unit it is realistically worth less than $75 USD to me, and I'd be hesitating to pay more than that in the future... Audio & tuner are functionally irrelevant though a dead LCD display is of no interest to me at any price.
The image to the
right is from an excellent Telequipment Scope that functions flawlessly
regardless of the temperature extremes of my workshop.
The signal is the audio that is marked as corresponding to Pins 2 & 3 constantly and pin 9 when the base unit is switched to Mono.
If I do get this unit functional, I will use the ear pieces to tie in a small PDA/MP3 player, or walkman.
This is the mother lode, Composite video signal. After scoping the ViewFinder and B/W Cam, it was easy to recognize. I'm now in the habit of sweeping a finger in front of the camera to watch a peak follow the outline of the shadow cast on the camera element.
This is pin 5, and seals the fate of the tuner and base as more junk. Pin 6 is the main voltage line at 5.33VDC and pin 7 is ground.
Pin 8 is the Backlit voltage line and can be ramped up or down over a range of 0.25 to 3.75 VDC. This control will initially be a variable resistor as a voltage divider, though I suspect that a zener diode or some other fixed voltage device will be established to set the intensity to the max without damaging the backlit for as much luminance as I can get, once the visor is blacked out.
Though not a major update the Virtual Visor Sport is a significant device and deserves to be explored in some detail before going much further.
In closing any additional info on the VV Sport would be greatly appreciated, especially schematic and parts list for the LCD panel. Additionally any source of replacement parts or cheap Right-Eye displays. The I-Scape appears to be based on the same LCD/focus prism methodology. Or if you're looking at this and know of an other device that approximates the same end please let me know, as the idea of a chunk of glass hanging below my eye doesn't thrill me if I end up getting to a bar fight or car crash.
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