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 This last winter, as I was looking for a new rocket project, I became interested in onboard rocket videos - I found that the added complexity gives flying rockets a purpose besides just going up and down. But where's the fun in just watching other peoples' videos? High quality onboard video for rocketeers is just a couple steps away!
My search for rocketry video systems yielded expensive video cameras, wireless video systems, and complex camera triggering devices. I'm sure these all work great - but I was looking for something cheap, simple, digital, and small enough to fit inside the 2.6" Cosmodrome Rocketry Nike Smoke I was working on at the time. The solution: a one-time use digital video camera from the local drug store (CVS Pharmacy), which happens to fit snuggly inside a 2.6" tube. The camera allows for 20 minutes of recording and lets the user erase the last video (in the event of a misfire or any other delay). The CVS video camera costs around $30. I wanted to design a downward-looking mirror attachment - it's pretty exciting to look at the earth fall away in a plume of smoke. Also, it's worth the extra work of making a mirror system in order to get a bird's-eye view of the launch site. The primary challenge of creating a downward view using the CVS video camera is compensating for the camera's off-center lens. Centering the mirror on the body tube would create an angled view of the rocket, so I designed the mirror attachment to be off-center like the lens, resulting in a line of view parallel to the body tube of the rocket. I positioned the camera between the bulkhead of the payload section (not standard with the kit) and the nosecone. I used four 6-32 screws fitting into tee nuts sunk into the balsa nose cone to secure the section. As long as you can easily open up and secure the compartment, be creative with camera placement. For larger airframe diameters, it may work to put a section of 2.6" tubing against the wall of the larger tube. The mirror housing is constructed from 1/4" basswood. I chose thick basswood for its light weight, ease of sanding edges into curves, and width for a strong attachment (and I had some scraps laying around). For the mirror, anything highly reflective should work. I happened to acquire a hard drive destined for the trash pile and cut out a small rectangle from one of the platters. Platters are surprisingly reflective! Before constructing the housing, I cut a 1" wide by 1-1/4" tall "window" in the tube (and coupler too) and reinforced the cuts with CA in order to reduce the risk of tearing. I mocked-up the camera housing with construction paper until I came up with dimensions shown. The housing is constructed from four pieces of wood. The mirror is made from a 1" x 1-3/4" piece of the hard drive platter which I cut with a Dremel tool. First, I glued the two side supports (parts # 1 and # 2) to the mirror support (part # 3). I next worked on beveling the edges of the side supports so they contact the body tube completely. I then glued the assembled pieces to the body. Following this, I put in the curved piece (part # 4) to fill the gap. Sanding is required to make the curved piece fit well. Finally, I used the Dremel to bevel the top and sides, following up the sanding by filling with epoxy. Wood glue may work, but I recommend 5-Minute Epoxy for its excellent filling and quick drying qualities. Before attaching the mirror, I painted the rocket. As a final note, make sure the rocket you are using has a sufficiently strong shock cord - the extra weight on the other end of the cord will increase the strain when it suddenly stops after ejection. I found this out the hard way (even with a nylon shock cord). The NAR section I fly with (SCRA) is kind enough to pause launching to let me start the camera just before flight, thereby greatly reducing the amount of costly footage of the rocket sitting on the pad. It typically takes me three or four minutes to turn on the camera, zoom in, position it in the tube, and seal-up the compartment. On my first launch, with an F40 motor, the rocket roared off the pad, and the mirror housing seemed to have no effect on the flight. The rocket has since then flown successfully on a G71, G77, G38, and a G76. Videos of these flights can be found at: http://www.rocketchutes.com/NikeFlights.htm Documents: RockSim file for Max's Cosmodrome Nike Smoke (133KB RockSim file) For Max's contribution of this article, he will receive a free one year subscription to LAUNCH Magazine. This sponsorship is made possible by our friends at MM Publishing, Inc., the producers of LAUNCH Magazine. Want your own free subscription? Read the program details page for complete information.
07-14-2008 11:47 AM
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Certified Level One
Joined: Aug 2007
Posts: 16
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Re: Building an inexpensive onboard video system
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07-14-2008 11:57 AM
#2
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If pigs had fins...
Joined: Sep 2007
Posts: 2711
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Re: Building an inexpensive onboard video system
Quote:
The interesting thing about NOT hacking it. Is that your investment of time and effort is very low and you are only out the $30.00 if you have a bad crash or a lost rocket.
Granted you pay more per launch for data - but there is a value to time invested isn't there? |
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07-14-2008 12:04 PM
#3
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Administrator
Joined: Jul 2006
Posts: 3165
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Re: Building an inexpensive onboard video system
Quote: The interesting thing about NOT hacking it. Is that your investment of time and effort is very low and you are only out the $30.00 if you have a bad crash or a lost rocket.
Granted you pay more per launch for data - but there is a value to time invested isn't there? Once you get the camera unlocked, it's just a matter of downloading the video onto your computer with the USB cable. A lot less time than running to CVS and getting a new camera, not to mention you save $30.
I've got one, unlocked with cable, I plan to use someday.  |
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07-14-2008 12:06 PM
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If pigs had fins...
Joined: Sep 2007
Posts: 2711
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Re: Building an inexpensive onboard video system
Quote: Once you get the camera unlocked, it's just a matter of downloading the video onto your computer with the USB cable. A lot less time than running to CVS and getting a new camera, not to mention you save $30.
I've got one, unlocked with cable, I plan to use someday.
I thought I had read that this unlocking only works on the original version. A new version is out now. |
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07-14-2008 12:26 PM
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Administrator
Joined: Jul 2006
Posts: 3165
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Re: Building an inexpensive onboard video system
The unlocking only worked originally if you hacked the camera. Later versions of the camera were unlocked with the Cronuskey unlocking software that was released and then spirited away due to litigious concerns. Seems someone discovered a public anonymous FTP server running on the manufacturer's site, and discovered the key-response code, allowing all units to be unlocked with software. There are copies of Cronuskey out there.  |
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07-14-2008 10:50 PM
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Certified Level One
Joined: Aug 2007
Posts: 16
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Re: Building an inexpensive onboard video system
I looked on CVS's website to see if they were still selling it but couldn't locate it. Are they still selling these cameras?
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07-14-2008 11:14 PM
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Certified Level Three
Joined: Dec 2006
Posts: 145
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Re: Building an inexpensive onboard video system
They have them in-store along with the single use cameras. Not on sale this week, but often $24ish and I was able to get several with a $10 coupon on the receipt. Use it when you purchase the next one.
Dig around, cvs camera hack and such. I've models 200, 220, and 230. Haven't seen others. I'm told the 200 model has the camera in a socket so you can put the camera in a remote area and run a cable. Haven't opened it yet.
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07-15-2008 10:34 AM
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If pigs had fins...
Joined: Sep 2007
Posts: 2711
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Re: Building an inexpensive onboard video system
Quote: I looked on CVS's website to see if they were still selling it but couldn't locate it. Are they still selling these cameras?
I saw two yesterday. $29.00 |
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07-15-2008 11:36 PM
#9
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Certified Level One
Joined: Aug 2007
Posts: 16
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Re: Building an inexpensive onboard video system
I found out they do not sell this camera over the Internet but only in the store.
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07-16-2008 12:01 AM
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Administrator
Joined: Jul 2006
Posts: 3165
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Re: Building an inexpensive onboard video system
You can get them on eBay, along with the cable to connect to them.
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07-16-2008 11:48 PM
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Certified Level One
Joined: Aug 2007
Posts: 16
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Re: Building an inexpensive onboard video system
I looked but I can't find one. What terms should I use in a search string?
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07-17-2008 11:28 AM
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Administrator
Joined: Jul 2006
Posts: 3165
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Re: Building an inexpensive onboard video system
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07-18-2008 11:24 AM
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Certified Level One
Joined: Aug 2007
Posts: 16
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Re: Building an inexpensive onboard video system
Rite-Aid also sells these cameras and these stores are in my area. I'll check there first.
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07-18-2008 12:48 PM
#14
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Administrator
Joined: Jul 2006
Posts: 3165
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Re: Building an inexpensive onboard video system
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07-18-2008 09:13 PM
#15
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Certified Level One
Joined: Aug 2007
Posts: 16
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Re: Building an inexpensive onboard video system
I did find one at Rite-Aid for $30. It is the model 220 which should be easier to hack than the model 230 based on some websites, forums, and YouTube videos I have taken a look at recently.
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07-18-2008 10:55 PM
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Certified Level Two
Joined: Nov 2006
Posts: 57
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Re: Building an inexpensive onboard video system
Ok what am I missing... why would you want to bother with these??
I saw a digital camcorder in Wal Mart last night for $29.95. No hacks, no cables, no shipping, you buy it you own it, you crash it you get another. No problem...
That would seem to work for onboard recording-- if you want downlink video the BoosterVision is a really nice and small unit, and the patch antenna will get your as much range as you want (within reason).
JMHO! OL JR |
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07-18-2008 11:01 PM
#17
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Administrator
Joined: Jul 2006
Posts: 3165
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Re: Building an inexpensive onboard video system
Quote: I did find one at Rite-Aid for $30. It is the model 220 which should be easier to hack than the model 230 based on some websites, forums, and YouTube videos I have taken a look at recently. Let me know if your search for CronusKey turns up empty. It's a lot easier than shorting pads and bricking camcorders. |
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07-18-2008 11:02 PM
#18
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Administrator
Joined: Jul 2006
Posts: 3165
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Re: Building an inexpensive onboard video system
Quote: Ok what am I missing... why would you want to bother with these?? Some things are more fun the harder they are to do. |
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07-20-2008 10:24 PM
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Certified Level Two
Joined: Nov 2006
Posts: 57
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Re: Building an inexpensive onboard video system
Quote: Some things are more fun the harder they are to do.
Okay I'll bite...
Rig up a couple of em for stereovision 3D...
I'll leave it up to the builder to decide on red/blue 3D filtering or polarization 3D and how to project it... OL JR |
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07-21-2008 10:57 PM
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Certified Level One
Joined: Aug 2007
Posts: 16
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Re: Building an inexpensive onboard video system
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07-22-2008 03:49 PM
#21
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New Member
Joined: May 2007
Posts: 80
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Re: Building an inexpensive onboard video system
Quote: Ok what am I missing... why would you want to bother with these??
I saw a digital camcorder in Wal Mart last night for $29.95. No hacks, no cables, no shipping, you buy it you own it, you crash it you get another. No problem...
That would seem to work for onboard recording-- if you want downlink video the BoosterVision is a really nice and small unit, and the patch antenna will get your as much range as you want (within reason).
JMHO! OL JR
I was sitting on the sidelines wondering the same thing. I buy yesteryear digicams that can do movies on eBay for cheap. I have crashed a few, no big deal. |
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07-24-2008 03:04 PM
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Roger Smith
Joined: Jul 2008
Posts: 7
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Re: Building an inexpensive onboard video system
Quote: Okay I'll bite...
Rig up a couple of em for stereovision 3D...
I seriously considered mounting two video cameras in a rocket to get 3D images. But, I realized that once the rocket is more than a few feet in the air, there really wouldn't be much of a 3D effect to the images. I've gone ahead with a two-camera rocket, but one camera looks straight out toward the horizon and the other looks down the rocket.
I use a couple of AIPTek cameras. They are a little more expensive than the CVS camera, but I didn't have to do any hacking.
-- Roger |
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08-04-2008 11:53 AM
#23
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New Member
Joined: Aug 2006
Posts: 4
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Re: Building an inexpensive onboard video system
Compare the frame rates on the cheaper camcorders. The CVS can do 30fps at up to 640x480. That's the reason I use them.
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08-04-2008 12:47 PM
#24
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Roger Smith
Joined: Jul 2008
Posts: 7
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Re: Building an inexpensive onboard video system
Quote: Compare the frame rates on the cheaper camcorders. The CVS can do 30fps at up to 640x480. That's the reason I use them.
The older Polaroid camcorders and the new AIPTek ones I use do 30fps at 640x480 (or higher) resolution. In reality, they don't really keep up with 30fps because of the compression of the video, but the results aren't bad for cameras that weigh just a few ounces.
But, these aren't the cheapest digital camcorders. They are more expensive than the CVS camera. They cost me about $70 to $90 each. But, in addition to not having to "hack" them, there are other advantages over the CVS camera. The shape of the cameras makes them easier to mount in a rocket (at least, for me). And you can use multiple memory cards so you don't have to transfer the video to a computer to re-use the camera.
In addition to catching on-board videos, I use the little cameras for taking close-up videos of launches. I use a roll of masking tape as a "tripod" to position the camera on the ground near the launch pad.
-- Roger |
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