rocknbil
03-22-2006, 02:57 AM
It's been too windy so the first success is a tour of my living room. More later when the wind dies down. Video first, then the "HOW" :D
6.5 MB streaming wmv (http://www.rc-resources.com/images/testvid/first_success.wmv)
This video is an edited down version of TWO flights, adding up to a total 18 minutes of flight time, two BCX batteries, with almost no noticable loss in performance.
Short history:
For the last month and a half I've been toying with the cheap onboard video cams you find all over eBay, mounting them in an E-Flite Blade CX. A sensible hobbyist would just get something that can carry a payload, but the minimalist concept intrigues me.
I've tried many things, and the largest problem is the BCX is not designed to carry the extra weight grams involved in the camera and cells to power it. Even with the first solutions proposed below, which brings the weight down to about 25-28 grams, you get about 60 seconds of flight time.
Quick review of what I've tried:
- ZT 802 Camera (http://www.chimaxco.com/ZT802.jpg): the video-only ZT 802 has a plug with a voltage regulator in it that CANNOT be eliminated from the system unless you substitute the RED wire in the plug for a 5V voltage regulator (both 9v and 5v must be supplied to the CMOS board.) While I've done this and it works, I've found better solutions as below.
- ZT 809 Camera (http://www.chimaxco.com/ZT809.jpg): Lighter, supplies sound, better CMOS and optics, and this cam is the one used in this video. This is also known as the ""Security Man Mini-Airwatch (http://www.securitymaninc.com/product/minairwatch.html)" system and the receiver supports up to 4 channels with a looping option - you can have up to 4 cameras operational and it will loop between them. More on looping cameras later, I have three of these units. :D
Both cameras require a mere 80mah to power them. So instead of the bulky 9v cell they normally run off of, I used two 160mah 3.7v lipo cells in series, which you can get from maxamps.com (http://www.maxamps.com). This will power these cams for up to an hour. Charging these on a DuraTrax VisionPeak at .15 amps, it takes about 5 minutes to peak each cell.
So this brings the weight down to about 25 grams. Still too heavy. Powering the cam off BCX battery works, but the voltage interference caused by the motors rendered the images worthless. RF coils, voltage regulators, and other attempts to filter out the noise failed.
So out comes the fine-tipped soldering iron and the Dremel, and the poor BCX you see in the pic below and the camera has undergone some major hacking. :D
The camera weight was reduced by removing the components from the case, affixing the CMOS board to the nose cone with low-temp hot glue, and replacing the tiny wires connecting the CMOS to the transmitter board with longer wires. This allowed me to move the transmitter board and the battery to the rear of the servos, balancing the fore-aft weight distribution. In the configuration below, the BCX is only slightly nose-heavy, which can be offset by sliding the battery back half an inch. Doesn't seem necessary, I've been flying it this way fine.
The lens is attached to the canopy by a rather cheesy method, as you can see - simple styrene scraps epoxied to the canopy - but this is a first experiment. Now that I know it works, a cleaner method will soon follow. Even so, note the tiny bolts protruding from the lens case - just snug enough to hold, but adjustable up or down. This is going to be an important capability if the wind dies down tomorrow. :D
To reduce the BCX weight, the rear fuse has been eliminated and replaced with a boom made of one of the fiberglas training rods. This boom is a little floppy, but it still flies fine and does not flop around enough to get into the blades or affect flight stability.
A simple scrap of lexan for tail feathers is all that's needed to help orient the bird in flight. The boom mount is integrated into the battery/transmitter board mount by a few small scraps of styrene plastic and tubing, all held together with CA.
The battery is held in place by velcro (second only to duct tape in our world) and the transmitter board is covered in simple sub-c cell shrinkwrap, then servo tape holds it in place. A rubber band over both offers insurance.
Because all this was done on the fly and I wasn't even sure it was going to work, I have no step-by-step pics and don't know the final weight of the camera and wires in it's modified form. I know the nose piece and transmitter comes in at around 11-12 grams, and the batteries are 10, so if I had to guess I'd say I'm at around 19-22 grams. I will weigh it all out on next disassembly.
As you can tell Im fairly hooked on this stuff so will be back with more video and improvements as I progress.
6.5 MB streaming wmv (http://www.rc-resources.com/images/testvid/first_success.wmv)
This video is an edited down version of TWO flights, adding up to a total 18 minutes of flight time, two BCX batteries, with almost no noticable loss in performance.
Short history:
For the last month and a half I've been toying with the cheap onboard video cams you find all over eBay, mounting them in an E-Flite Blade CX. A sensible hobbyist would just get something that can carry a payload, but the minimalist concept intrigues me.
I've tried many things, and the largest problem is the BCX is not designed to carry the extra weight grams involved in the camera and cells to power it. Even with the first solutions proposed below, which brings the weight down to about 25-28 grams, you get about 60 seconds of flight time.
Quick review of what I've tried:
- ZT 802 Camera (http://www.chimaxco.com/ZT802.jpg): the video-only ZT 802 has a plug with a voltage regulator in it that CANNOT be eliminated from the system unless you substitute the RED wire in the plug for a 5V voltage regulator (both 9v and 5v must be supplied to the CMOS board.) While I've done this and it works, I've found better solutions as below.
- ZT 809 Camera (http://www.chimaxco.com/ZT809.jpg): Lighter, supplies sound, better CMOS and optics, and this cam is the one used in this video. This is also known as the ""Security Man Mini-Airwatch (http://www.securitymaninc.com/product/minairwatch.html)" system and the receiver supports up to 4 channels with a looping option - you can have up to 4 cameras operational and it will loop between them. More on looping cameras later, I have three of these units. :D
Both cameras require a mere 80mah to power them. So instead of the bulky 9v cell they normally run off of, I used two 160mah 3.7v lipo cells in series, which you can get from maxamps.com (http://www.maxamps.com). This will power these cams for up to an hour. Charging these on a DuraTrax VisionPeak at .15 amps, it takes about 5 minutes to peak each cell.
So this brings the weight down to about 25 grams. Still too heavy. Powering the cam off BCX battery works, but the voltage interference caused by the motors rendered the images worthless. RF coils, voltage regulators, and other attempts to filter out the noise failed.
So out comes the fine-tipped soldering iron and the Dremel, and the poor BCX you see in the pic below and the camera has undergone some major hacking. :D
The camera weight was reduced by removing the components from the case, affixing the CMOS board to the nose cone with low-temp hot glue, and replacing the tiny wires connecting the CMOS to the transmitter board with longer wires. This allowed me to move the transmitter board and the battery to the rear of the servos, balancing the fore-aft weight distribution. In the configuration below, the BCX is only slightly nose-heavy, which can be offset by sliding the battery back half an inch. Doesn't seem necessary, I've been flying it this way fine.
The lens is attached to the canopy by a rather cheesy method, as you can see - simple styrene scraps epoxied to the canopy - but this is a first experiment. Now that I know it works, a cleaner method will soon follow. Even so, note the tiny bolts protruding from the lens case - just snug enough to hold, but adjustable up or down. This is going to be an important capability if the wind dies down tomorrow. :D
To reduce the BCX weight, the rear fuse has been eliminated and replaced with a boom made of one of the fiberglas training rods. This boom is a little floppy, but it still flies fine and does not flop around enough to get into the blades or affect flight stability.
A simple scrap of lexan for tail feathers is all that's needed to help orient the bird in flight. The boom mount is integrated into the battery/transmitter board mount by a few small scraps of styrene plastic and tubing, all held together with CA.
The battery is held in place by velcro (second only to duct tape in our world) and the transmitter board is covered in simple sub-c cell shrinkwrap, then servo tape holds it in place. A rubber band over both offers insurance.
Because all this was done on the fly and I wasn't even sure it was going to work, I have no step-by-step pics and don't know the final weight of the camera and wires in it's modified form. I know the nose piece and transmitter comes in at around 11-12 grams, and the batteries are 10, so if I had to guess I'd say I'm at around 19-22 grams. I will weigh it all out on next disassembly.
As you can tell Im fairly hooked on this stuff so will be back with more video and improvements as I progress.