Wednesday, July 18, 2012

LCD monitor / NVG Helmet Mount interface

Shown below, is a copy of an old-school, US Army issue, NVG Rhino mount, used for attaching an NVG (night vision goggles) system to a helmet.  I purchased this mount from one of several eBay Airsoft sellers in Asia for about thirty dollars including shipping.
Airsoft NVG Rhino Mount with "Ops-Core" style attachment shroud
Ops-Core style VAS Shroud (Airsoft)  $19.98 incl. S&H
This slot will allow the viewer to move laterally left/right if needed.
VELCRO LOOPED AT BOTTOM
Here is the setup attached to a FAST Base Jump helmet.

                                    

This one cost me $13.75 including shipping from seller - greatfoto, but there are multiple other sellers of this item on eBay.
Coming up next: Attaching GoPro with LCD Backpack to the Rhino Mount.
You can try multiple. alternate eBay searches for the same thing: NVG mount, PVS mount and Rhino mount.
The final element to the project, is an LCD viewfinder/shade hood which acts as a magnifier, as well as a shade hood for viewing the monitor in bright sunlight.  The eBay item was listed – “2.8X V3 magnifying lens LCD Viewfinder FOR Canon 600D/60D.”


These Airsoft devices are NOT designed to hold actual NVGs, which are both very heavy and very expensive, but these reproductions, are fairly solidly made out of metal parts and can easily and safely carry the minimal weight of my mini-monitor system.
The Airsoft Rhino Mount I bought included an aluminum VAS (Vision Augmentation) shroud which can be installed on a helmet if your helmet doesn’t come with an NVG attachment point already.  It comes with mounting hardware, and can be easily installed on some motorcycle and PPG helmets by simply drilling 3 holes.
VAS base shrouds are also available separately.  Apart from adding a kind of cool, technical look to a helmet, NVG base shrouds can also be set up to mount visors, flashlights, headlamps, and as this project shows, you can attach a monitor to frame your shots while in the air.
GoPro produces an NVG camera mount which is available for between 30 and 40 dollars, or you can make one yourself for around ten dollars using a NVG QD cover plate available from various Airsoft suppliers around the world.  See my post for a Do-it-Yourself NVG mount for a GoPro Camera.
My flight helmet is a non-ballistic, sport version of a military helmet made by Ops-Core, called a “FAST Base Jump Sport" helmet.  See my review of the Ops-Core helmet here.  It has an NVG mount integrated into the front of the shell, which can hold either a GoPro in an NVG Camera Mount or this project's monitor mount system.  Or actual night vision goggles, if you’re crazy enough to fly at night like this guy is doing.http://www.youtube.com/watch?v=71RCRguWJAU  (Youtube – "Paramotor flying with nightvision.3gp") All completely illegal, of course, probably pretty much everywhere, but pretty cool nonetheless.

Authentic Rhino mounts sell for upwards of a couple of hundred dollars brand new, but I have seen used mounts regularly sell on eBay for LESS than what I paid for my copy.  Trouble is, there are strict rules about the export of these items out of the USA, so unless you live in the US, you will probably have to be satisfied with the Airsoft version.  A real unit would be preferable in my opinion, however, if you happen to live in the US, and have the time to wait for a deal on eBay.  My copy is a little bit crooked, and the detachment button is a bit sticky. 


NVG Rhino mounts have a second part, called a J-Arm, that snaps into the front of the mount and holds the actual NVG monocular or binocular in place, but the J-Arm isn’t necessary to make this project, and good luck getting one of these parts if you live outside of the USA.  The Airsoft version of the J-arm is reputed to be junk.

Also, I don't think a J-arm will work for this project, as most people will probably want the monitor to be a few extra inches from their eyes in order to focus anyway, so the J-Arm isn’t actually needed.

Are we sitting comfortably?  Good, then lets begin.

You’ll need:
An NVG Rhino mount - or a copy, costing about $30.00 shipped.
An Equinox 2.5” monitor, (about $55 shipped via eBay) and appropriate connectors and cables.  You can also use the GoPro Backpack LCD monitor, and these aftermarket cables here: http://www.chargeconverter.com/store/sandisk?product_id=157 This cable is engineered to use the GoPro's HD backpack "bus" interface, and allow you to view the LCD Backpack separated from the camera, but the Equinox provides a larger view area, is only about half the price, and also features internal power.  The GoPro LCD back pack is a power pig, and will significantly cut into your GoPro battery power.

You’ll also need:
-A strip of aluminum, steel, or steel scrap, about 3” long, and between 1 3/8” and 1 1/2" wide. 
-Some zip ties, and,
-a drill, and maybe a Dremel tool with a cut-off wheel.  And a small Torx screwdriver.

The object is to create a new J-arm for the mount that will be a little further forward than the one designed for actual night vision devices.  It will also be flat, perpendicular to the horizon, unlike an NVG arm which is curved downward.
 
You'll need a piece of aluminum scrap about  1.5" X 3" and at least 1/16" thick.  Cut a basic J shap, and drill four holes for the zip ties.  You will also need to make a slot for the 1/4" tripod screw so you can attach the shade hood.  I drilled two holes and Dremeled out the space between them, so I can later adjust the mount when worn on a helmet.  The completed mount can now slide a little left to right as needed.


Drill a hole (2-holes actually) for the 1/4 inch tripod screw you will be attaching.  Dremel the holes to make a slot, so you can ultimately get some sideways adjustment for your viewer.
Using a small Torx screwdriver, remove the plastic block behind the J-Arm receiver on the mount.
Zip tie the monitor to the J-arm receiver.  I spray painted mine with black laquer paint firs
The J-Arm receiver will slide forward and backwards and lock into eight different positions.  When not being used, the monitor can be slid into the rearmost position, and then slid forward when you’re in the air, and want to frame up your shots.  (The arm is currently in its forward-most position in the pictures above.)



Attaching the monitor itself to the Viewfinder, shade hood was a challenge, and here is my solution.  

You'll need two very small zip ties, (100mm) attach two holes drilled at the corners of the strap attachments on the monitor, and two corresponding holes in the metal of the attachment frame.




It wont work so well on the thinner bottom edge, and you need that edge clean and flat so the magnets on the shade hood will keep the hood solidly attached.  So I sewed a strip of 3" X 1 1/4" nylon fabric to the bottom, and two strips of hook and loop Velcro.  

A little epoxy cement under the fabric keeps it from moving after it is sewn on. This thin fabric that loops over the bottom section of the mount, in the picture below, does not interfere with attaching the magnetic shade hood.  


And the Velcro allows the monitor can be opened up from the back for battery change-out, if you are using the spare batteries that are cheaply available.  However, you can charge the monitor battery without opening the thing up if you prefer, so this last sewing stage can be a glue job instead of hand sewing, or machine sewing the strap and Velcro.
Here it is with the monitor flipped up and out of the way.
And finally, shown utilizing the magnetic shade hood.  Apart from making a superb sun hood, allowing the screen to be seen in the brightest glare conditions, the 2.8 power magnification eyepiece makes it ideal for people who need reading glasses to see stuff.

You don't need to use the magnifying shade hood, but I like to, and not just because the magnifier helps me see fine detail.


A word on the eyepiece:  The magnets may want to pull away from their plastic slots on the hood.  So I used a drop of epoxy under each of the four magnets to keep them from ever coming out and getting lost.  But once you get them permanently glued, the shade hood clips on pretty snugly, with corner protrusions that center the device, and it sort of "clicks" into place.

When flying, I keep the hood on a lanyard around my neck so I don't lose it.  I wouldn't rely on the magnets alone to keep it attached, as the magnetic attachment alone would never survive the knocks of a typical flight. For the most part, the LCD viewer is visible in daylight conditions, and the hood need only be swung up and clipped on occasionally.

2 comments:

  1. What kind of radio/headset do you have?

    ReplyDelete
  2. had an great experience with this LCD monitor and fabulous LCD Monitor

    ReplyDelete