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questtek's blog
Posted by questtek | Nov 06, 2006 @ 09:33 AM | 20,063 Views
In a previous blog I outlined the modifications I made to turn a 5 oz. inexpensive digital camcorder (sub $30 and as low as $19 with coupons) into a lightweight, 2 oz. RC video camera with 20 minute video record capability. In this blog I show the mounting of this stripped digital video camera to a foam UFO that was designed and built by my friend Steve Z. This UFO can be made to "hover" much like a helo but can also do full 3-D stunts.

Unfortunately Steve had an electronic "flame out" on the first flight and the plane crashed...big time! I recovered the camera, cleaned off the mud and grass and mounted it to a second foam UFO. I have included a video of this first successful flight however the areal video is a bit soft, (professional term for being slightly out of focus). The soft focus was a result of the previous crash and not rechecking the focus prior to flying it again. In any case you can see the potential that these inexpensive digital video cameras can bring to the entire RC community.

To see the video from the first UFO flight:

http://s92.photobucket.com/albums/l3...=UFOvideo1.flv
Posted by questtek | Nov 05, 2006 @ 01:40 PM | 21,347 Views
There appears to be an accelerated interest in RC video as a result of lighter and less expensive video equipment. The Video section of this RCgroups site has several entries on the application of an inexpensive, sub-$30, digital video camera. The downside is that this digital video camera is a one-use camera and must be sent in for the video to be "unlocked" and a DVD returned to the user...naturally without the camera being returned. These digital video cameras are sold at Rit-Aid, CVS, Ritz camera, etc. Thanks to the "Hacker" community, these cameras can now be "unlocked" so that they can be reused and the video easily downloaded from the cameras onboard memory to a Windows-based PC. If your Mac runs PC emulation I am pretty sure it can also be used.

The technology and methods to "unlock" this camera can be found on the video forums on the RCgroups site and will not be repeated or addressed here. The intent is to show you MY hardware modification to this camera for RC applicaitons.

With modifications:
1. the camera overall weight will be 2 oz or 58 grams
2. the camera circuit board will be protected
3. a new, multi-function electrical 4-pin connector will be added to the camera can be interfaced to any RC receiver or USB computer plug.
4. camera power will be from the 5 vdc available at the red and black lines of the 3-pin receiver plug.
5. the size of the camers is 3.7" x 3.4" x .5" thick (with the exception of the lens and mic extension.
6. Color LCD screen is fully functional to verify camera in REC mode and to check mounting alignment.

I have included a series of pictures that show the hardware modifications to the camera. PLEASE do not e-mail me or ask questions on the software techniques to "unlock" the camera...this is already available by looking at the topics in the video forum already posted. My intent here is to document one approach to the modification of this unique, inexpensive video digital recorder.

Best and Good Luck, Joe
Posted by questtek | Oct 27, 2006 @ 06:51 PM | 19,831 Views
In a previous blog I showed a 28 gram digital video camera onboard an airboat...along with some video of the boat, not me, chasing some marine birds, coots, that co-inhabitat the lake I live on. Easy...almost Duck Soup, say the airplane wizzards on RC groups. So, with the help of my very inexpensive Slo-Stick, I mounted the camera and made a few quick videos. This Slo-Stick is totally stock and the real el-cheapo model with its 64 cent brushed motor, etc. The velcro strips to hold on the camera were probably more expensive than the motor.

The first video shows flight test #1 with the camera mounted downward, onto the wing with velcro, in a low-level flight over a parking lot.

The second video, Flight #2, has the camera mounted in a forward looking direction....and you see the prop throughout the flight.

I included a picture of a ribbon cable extension from the lens to camera board. This has the potential of mounting the camera head to a tiny servo for full directional video control. The additional circuit board is to permit 12 VDC operation, plus interface with a USB data recording module. This module would not be required in normal RC applications.

With the first tests reasonably promising, I will develop a gimbaled mechanism for the camera and improve on the electronics. For the video see:

http://s92.photobucket.com/albums/l3...tickVideo2.flv
http://s92.photobucket.com/albums/l3...ickVideo1a.flv
Posted by questtek | Oct 22, 2006 @ 06:17 PM | 21,032 Views
Having had a bit of luck with a tiny 27 gram digital still camera on my electric airboat I wanted to now try a 28 gram color digital video camera. Unlike a still camera where trigger action is required, the digital video camera module requires only power, supplied by a spare Sony LiIon cell, and a record/pause trigger in the form of a momentary switch.

The pictures below show the digital video camera module, red power connector and record/pause trigger. I built a simple water proof housing out of a section of clear acrylic tubing. Since the video would be distorted through the plexiglass tube, I added a precision optical glass dome. I compressed the video significantly and the included video does not do the quality justice but I wanted the entire video file to be less than 9 megs. With the 5 Megapixel sensor on the camera, the uncompressed results are fantastic.

One major benefit of the board I am using is that there is a video and audio output so I could also incortorate a 1.2 or 2.4 Ghz miniature wireless transmitter......all within the same tiny water proof housing.

You can watch the airboat interact with a flock of coots at:

http://s92.photobucket.com/albums/l3...gAnch=imgAnch1
Posted by questtek | Oct 21, 2006 @ 08:15 PM | 20,654 Views
Years ago I helped develop a digital camera that was integreted into a "Taser-type" weapon. When the gun was pulled out of the holster the camera power was turned on and it started recording as soon as the safety was pulled off. It provided a great record of the events that followed....and more.

Using a similiar concept I modified an ultra-miniature digital camera (only 27 grams complete including memory and all connectors), so that it functioned the same way...or close to it. It has a single lead that goes to any open receiver plug. I built a power conditioning circuit so the input voltage could be the typical 5 VDC all the way to 12 vdc. When the receiver power is turned on, the camera is turned on. There is a delay then digital pictures can be taken. It can be set up as a one-shot controlled by an open transmitter switch (like landing gear retract), or it can be set in the auto-sequence mode. Currently it is set at a picture every 6 seconds. WIth a 60 picture storage that amounts to getting digital pics for about 6 minutes. I will probably make the time interval selectable by a small pot so sequence times can vary from 5 to 30 seconds.

I find the auto sequencing is just great. There is no thought to the pic taking, you just download the entire camera memory via USB to a computer and select the pics you want. I included some pics of MY VERY FIRST USE on the lake where I live.....chasing some birds. You can see me operating the transmitter from a...Continue Reading
Sticky: RC Duck
Posted by questtek | Oct 15, 2006 @ 06:31 PM | 30,684 Views
The lake that I live on has a wide assortment of birds, including two, very aggressive female white swans. The females get hyperactive when the newborn Canadian Geese and Malards start to hatch out, often going after them with the intention of killing them. We loose quite a few young waterfoul just as they are learning to swim as a result of the dominant white swans.

I thought I would help the balance of nature a bit by introducing a rather small duck that was not only not afraid of these large swans but would go after them.
My duck was RC controlled, high speed and got the job done. While it is doubtful if you can teach swans....they certain learn to fear things they do not understand.

The attached pictures show a pair of plastic duck decoys that can be purchased at most hunting stores for less than $10 a pair. I designed a "boat-type" insert that fits into the bottom of one of the ducks. It contains an underwater 12 vdc motor with 4 bladed prop that is pivoted by a servo in the dry, upper compartment. This compartment also holds a 12 VDC, 10 cell NiMetal Hydride pack, Hi-Tek receiver and marine speed controller. All simple stuff. The power is turned on by a tiny waterproof switch protecte by a red rubber boot located under the tail.

Hope this brings a few smiles to my RC boating friends...........after all, it is not always about speed!
Posted by questtek | Oct 12, 2006 @ 01:19 PM | 25,622 Views
In response to a post concerning an electric assist on a surfboard, I am enclosing a video of some preliminary tests of a dual electric water jet propulsion system on a Scuba Diver. Keep in mind, the drag of a Scuba diver underwater is about 100 times greater than a surfboard setting on the water
To see the video:

http://s92.photobucket.com/albums/l3...JetTesting.flv
Posted by questtek | Oct 11, 2006 @ 06:16 PM | 32,890 Views
As part of a prop for a proposed TV series called "Close Quarters", I designed and built an RC Great White Shark Fin. I have included several pictures so that anyone interested can view the construction techniques. The framework is Lightweight PVC with a sealed battery pod and two underwater 12 VDC motors on the bottom and electronics sealed in a waterproof box on the top. The bottom battery pod has 10 NiMetal Hydride cells in a PVC tube with waterproof connector. This connector is used both for charging and turning the unit on. The electronics are two speed controllers for the motors and another speed controller that operated a miniature 12 VDC pump. (just aft of the yellow electronics box). This miniature pump is connected to a jar that contains "Blood" in the form of harmless and environmentally safe red food coloring.

Directional control and to make the shark swim, chanels 1 and 3 of a 4- channel radio are used. The right stick controls the right motor and the left stick the left motor. With this set up it is easy to "swim" the shark fin....and even make it go in reverse, something a Great White has a bit of trouble doing.

I made a small video on the operation of the shark fin on a lake that I live. Across from my house on the lake is a pre-school. When I "swam" the Great White Shark fin near the play ground at recess, the yelling and screaming was so loud from the children I had to bring it back into my dock!

For a bit more realism, I included some pics of a swimming shark cage used in a recent 1 hour TV special, "Mind of the Demon' that I worked on with Jacques Cousteau's grandson.

See the shark fin video at:

http://s92.photobucket.com/albums/l3...rkFInMovie.flv
Posted by questtek | Oct 09, 2006 @ 06:33 PM | 22,670 Views
In response to an RC group member that wants to put a few electric motors in a surfboard or boggie board, I have included some pictures of a test setup I am using to evaluate thrust for various brushless motor / LiPoly battery Packs. The system shown has a 800 watt brushless motor connected to the water jet drive input via a flexible coupling. I use an Astro meter to measure volts, amps, power, etc at various speed settings. On the bow is a manual servo controller tht permits me to adjust the speed without a transmitter and receiver. It connects directly to the Castle Creations speed controller. To measure thrust I use a digital "Fish Scale". It will measure and record thrusts up to about 50 lbs.
I show the scale set up on my dock but naturally the boat is in the water for all tests, thus the scale and Astro display are easily visible. The white canard boat is simply a test vehicle, nothing more. I use a waterproof plexiglass hatch so I can view things inside the boat while it is running. Note that I had to add a 6 lb lead weight to the back of the boat to insure the water jet drive intake (at the bottom of the hull) and the high pressure water exhaust were under water.

Hope this gives you some ideas for your testing. Best, Joe

Here are the test results:
Thrust 5 lbs
Amps 30, Watts 450, Volts 15
Next series of tests will use a 6 cell 8000mAhr LiPoly pack.
Posted by questtek | Oct 09, 2006 @ 01:50 PM | 28,575 Views
The following pics provide an overview of an underwater ROV eyeball that I created. It used two 420 line Sony board cameras facing fwd and aft in two precision glass optical dome ports. Propulsion is by two small waterproof electric motors with magnetic couplings so there are no o-ring seals. The cable to the surface provides the video signal(s) in addition to the RC control signals. While the RC frequencies will not transmit through water at any great distance, you can send them along a single wire for very long underwater distances. It has been a great tool to explore the bottom on the lake that I line on....and maybe to find some of those sunken RC electric boats I lost!
Posted by questtek | Oct 08, 2006 @ 04:04 PM | 26,431 Views
A majority of my work related to RC boat video has been wireless re-transmitted video. I have built small research vessels with up to 4 onboard video cameras, including underwater cameras, that send siglals back to a remote station via a 1.2 Ghz or 2.4 Ghz microwave link. Viewing the received image in sunlight has always been difficult so I thought I would experiment with putting a tiny but high resolution camcorder that records to SD memory card onboard. (It also as a digital image stabilization feature) I used a special optical glass dome to house the tiny digital camcorder and make it totally waterproof with minimum weight. The camcorder LCD on the side permits me to view alignment when mounted to the boat. The black button on the back of the housing is the start switch. I can confirm the camera is recording by the LCD screen also. I designed the unit so that it could be easily removed via 3 stainless twist fasteners.

The Camcorder module is mounted to the front of a motified fiberglass cat. I am running a large brushless outrunner motor turning either an 8 or 4 bladed 10x8 prop. I use an 8000mAhr LiPo 4 cell pack for power. All the electronics and battery are easily accessible via the twist waterproof hatch. If anyone is interested, I can post some video. Hope this stirs some creative brain cells.

Best, Professor Joe Valencic
Posted by questtek | Oct 08, 2006 @ 03:52 PM | 22,352 Views
There is a large interest in airboats on various RC forum sites. Most airboats use gas engines with a few starting to use brushless electric motors. I have recently been experimenting with brushless ducted fans with GREAT success. The attached pics show an ultra-light fiberglass cat running twin ducted fans powered by 35 amp speed controllers and a 3-cell, 8000 mAhr LiPo battery. I use a Y servo connector and thus a single stick for speed and turning (by varying the speed of the appropriate ducted fan). It not only screams but my arms get tired running it before the battery ever wears out. Note that I installed an ultra high power 120,000 mcd white forward running LED and a 11,000mcd Blue LED for the stern for night running. I live on a lake which makes operation and development very convenient!
Best, Professor Joe Valencic
Posted by questtek | Oct 08, 2006 @ 03:20 PM | 21,865 Views
The attached pictures show a 1/8th scale model of a "vehicle" I am developing that will serve as both a car and boat. Of special interest is the design of the wheel/propellor drive system. Dual brushless motors are used in a right angle housing and controlled via wireless "sonar" switches in the cockpit. Lithium batteries are used for power. The advantage of the drive system is that the right and left sides are identical and can be replaces as a single water proof unit. Hope this post stirs some creative thought.
Best, Professor Joe Valencic
Posted by questtek | Oct 08, 2006 @ 03:14 PM | 22,167 Views
The attached pictures show a 1/7th model of a concept I am developing, (the larger yellow canard) I am Senor Scientist R & D for Exomos submersibles www.exomos.com While we build submersibles and jet powered surface boats, my latest concept is a two person electric vehicle that is a combination boat, car and.........submersible. The "car" aspect will use the drive system in the pics...geared brushless motors, while the boat and car will use jet drives coupled to brushless motors. For the actual vehicle we will use the latest Lithium Chromium batteries that we use in the "special" class of our Exomos submersibles. A following post will show an alternate wheel/prop drive I am experimenting with. As you can see, RC models play an important role in demonstrating unique engineering concepts before they are launched into actual, limited production vehicles.
Best to all, Professor Joe Valencic
Posted by questtek | Oct 05, 2006 @ 11:46 AM | 22,035 Views
I am a professor of Oceanography and senior scientist for R & D at Exomos Submersibles. (www.exomos.com) I developed some unique technology for marine monitoring using fiberglass RC cats equipped with Pentium computers, GPS and topside/underwater color video cameras including wireless links. I thought I would share this with other RC boaters....possibly others have done similiar things and can share their experiences. The vessels are a meter long and have a wide variety of propulsion configurations from brushless U/W props, to brushless air prop drives, to brushless turbines with 10 lbs of thrust. Hope you enjoy the pics. Included are pics of NOAA using 6 of the boats for research and education in Hawaii.