Aiptek Pen Cam Carrier

[tbzep]

At the request of a few folks, here's a few shots of my Aiptek Pen Cam Carrier. This rocket began its life as a Stormcaster. I built this thinking it would be lost within a few flights, especially when flown here on a D12-3, so I didn't even bother painting it until recently. I was partially correct. I lost the booster section to a rocket eating tree, but the heavier camera payload was safely recovered with a 12" chute and a large spill hole. I forgot to put a spill hole in the 12" booster chute.

I slapped together a new booster and put twin 18mm mounts so that I could get high thrust with low total impulse for small field use. C11-3's are not to be found anywhere around here, so a pair of B6-4's make a nice boost. It flew on a pair of C6-7's recently, for another nice boost. It ejected well after apogee, but that was in a strong wind. Calm air will likely give an ejection close to apogee.

The payload section is set up to be as cheap and easy as possible to make and use. I just made rough cuts and "that looks about right" measurements. Nothing about this could be considered precision. I cut the payload to length where the camera would fit within the tube and tube coupler. I used some weatherstrip self stick foam in the bottom of the tube coupler to take a little stress off the body tube where the lens protrudes. I added some more foam to the back of the little camera so that it would be forced forward against the body tube. The lens fits into a hole and is kept there by the foam. This locks the camera in place without any fancy mounting bracketry.

The camera has to be removed to upload the video and to replace batteries. I added tape to the nosecone to make a nice tight friction fit in order to make it easy to access. I added a little twisty tie to the keyring on the top of the camera to make it easy to pull out. Yep....cheap, simple, easy, light weight.

 

[tbzep]

The back has two rough cut holes in order to be able to see the LCD and to turn the unit on and set it to video mode. One more hole is cut above and to the right in order to be able to access the shutter release, which also starts the video. At launch, I just take a wire or small screwdriver and push the button to get video mode, then push the shutter button to start recording.

LCD screen and on/mode button

Shutter release/video record button access

The recovery sling is also a quick and dirty method. I cut a small groove into the tube coupler so that the shock cord material would fit and allow smooth separation at ejection. I plan to add some length between the chute and the harness next time to lengthen the moment arm and hopefully help slow the swing enough to get better video on descent.

 

[Blades]

Very cool. I like the idea of a cheap and easy way to do this. I'm gonna have to make one.

 

[paparoof]

any chance we can see some sample video? I'm interested in seeing what kinda quality you get outta that pencam - that looks like the one Aiptek sells for 10 bucks on their website - is it?

 

[Race58]

You will find all your answers here.
I don't think Tim has posted the actual video yet but there are some real nice pictures taken from the video in this thread that I think will show you the quality.

https://www.rocketryforum.com/showthread.php?t=44808&highlight=shelby

Yes the camera he used is the $10 one. He has a link to it in the thread I listed here.

any chance we can see some sample video? I'm interested in seeing what kinda quality you get outta that pencam - that looks like the one Aiptek sells for 10 bucks on their website - is it?

 

[tbzep]

any chance we can see some sample video? I'm interested in seeing what kinda quality you get outta that pencam - that looks like the one Aiptek sells for 10 bucks on their website - is it?

IMHO, it isn't worth a plugged nickel for video. Frame rate is too slow. I'll see about putting it on Youtube (never used Youtube before). The file is large and I don't want to max out my photobucket bandwidth.

 

[tbzep]

Ok....finally got the video uploaded. In calm air, the roll rate of the booster is perfect to get a couple of revolutions for a good panoramic view. Since it was very windy, the rocket was tipped into the wind, so the roll produced ground/sky images instead of panoramic horizion shots it normally gives me.

As you can easily see, the little camera is best suited to be set on video and grab frames to use as still images. Hope you took your seasick pills!

I have a tv downlink system that I use for regular video.

 

[DaveHein]

The PenCam is a good little camera. I like to use it in the still mode, but it requires some external circuitry to take pictures in this mode. I have carried a PenCam in a StormCaster and an Executioner. Here's a picture of the StormCaster.

<img src=https://home.swbell.net/davehein/ModX/StormCaster2.gif>

Click <a href=https://home.swbell.net/davehein/ModX/StormCaster.html>here</a> for more information on this rocket.

This camera has taken some nice pictures. It does suffer from a skewing artifact if the camera is moving while it is taking a picture. I wrote a program to undo some of the artifacts, and some pictures turn out pretty good. I also hung the PenCam from a kite when I can't fly rockets on windy days. Here some of the pictures I taken with the PenCam. Click on the "All Sizes" link on the photo page to see the full-res version of a picture.

Dave

<a href=https://www.flickr.com/photos/davehein/1196488904/in><img src=https://farm2.static.flickr.com/1181/1196488904_1efd5e5827_m.jpg></a><a href=https://www.flickr.com/photos/davehein/777076557><img src=https://farm2.static.flickr.com/1358/777076557_a7f0dd3664_m.jpg></a><a href=https://www.flickr.com/photos/davehein/527601226><img src=https://farm2.static.flickr.com/1173/527601226_ba7d9963cf_m.jpg></a><a href=https://www.flickr.com/photos/davehein/472816876><img src=https://farm1.static.flickr.com/231/472816876_dfc0816b86_m.jpg></a>

 

[tbzep]

Dave,

How many frames do you get with the still camera mode and electronics pod?

 

[DaveHein]

The PenCam's flash memory seems to degrade fairly quickly over time. Initially, a PenCam can store about 100 pictures at a rate of about one picture every 8 or 9 seconds. After taking a few hundred pictures the time to take a picture increases to about 10.5 seconds. I programmed the controller to take one picture every 11 seconds.

The number of pictures it can store also degrades over time. My current PenCam can only store about 30 pictures. My first PenCam got to the point where is could only store a few pictures before the camera completely failed.

Dave

 

[tbzep]

The PenCam's flash memory seems to degrade fairly quickly over time. Initially, a PenCam can store about 100 pictures at a rate of about one picture every 8 or 9 seconds. After taking a few hundred pictures the time to take a picture increases to about 10.5 seconds. I programmed the controller to take one picture every 11 seconds.

The number of pictures it can store also degrades over time. My current PenCam can only store about 30 pictures. My first PenCam got to the point where is could only store a few pictures before the camera completely failed.

Dave

Speaking of PenCam shortcomings...

It doesn't like rechargable batteries either. I lost video on three sucessive flights with brand new rechargables. I got good captures on regular alkalines both before and after trying the rechargables.

 

[Tom Swift]

I wrote a program to undo some of the artifacts, and some pictures turn out pretty good.

More info on that program please!

 

[DaveHein]

More info on that program please!

It's a fairly simple C program that shifts each line based on a second-order description of the skew. I would determine the amount of skew by measuring the angle of vertical edges in the image at different scan lines. I then did a least-squares fit of the angles to a straight line. Integrating this equation gives a second-order description of the shift for each line.

This works pretty well if the camera is spinning around the long axis, which is normally the case when it looks out the side of a rocket. If the spin is at a constant rate the skew will be constant. If the rate of spin is slowing down or speeding up the skew can be aproximated by a second order equation.

Dave

 

[Tom Swift]

That's pretty hardcore. Even if I could remember that kind of math from college (20-odd years ago), I'm not up to the programming task. And I have no experience with electronics to build an external controller. I really admire your skills!

I have just ordered an Aiptek and there's a Stormcaster somewhere in the build pile... I'll just keep it simple; use the video mode, select a few choice frames as stills, and adjust the skew in Photoshop Elements.

That might be good enough for now. Until Estes comes up with an improved Oracle or Astrovision. Or until Google Earth gets a "live" mode.

By the way, surely someone has tired using one of these in a rocket? For sale on ebay for about $55.

 

[Race58]

WOW, Tim you wren't kidding about those seasick pills:surprised:
Ed

Ok....finally got the video uploaded. In calm air, the roll rate of the booster is perfect to get a couple of revolutions for a good panoramic view. Since it was very windy, the rocket was tipped into the wind, so the roll produced ground/sky images instead of panoramic horizion shots it normally gives me.

As you can easily see, the little camera is best suited to be set on video and grab frames to use as still images. Hope you took your seasick pills!

I have a tv downlink system that I use for regular video.

 

[tbzep]

WOW, Tim you wren't kidding about those seasick pills:surprised:
Ed

With the wind blowing a half jillion mph, even sitting on the pad the thing was rocking and rolling. Couple that with a short moment arm on the chute and the little camera was whipping all over the place after ejection. The slow booster spin would have been nice had the rocket ascended vertically, but the wind put it on its side pretty quickly and wasted frames on the sun. I'll try a few things to make the post ejection a little better. I was thinking about knocking out the spin during ascent, but I've decided that I like the ability to get a full panorama so it will stay as is until I destroy or lose the booster. If it were a downward pointing camera, I'd try to eliminate the spin.

 

[Rocketlady]

tbzep,

I like your easy to set-up camera mount. Did you need to do any mods to the camera for an auto-start or anything?

 

[Micromeister]

TZZAP:
I've put all my various camera project on permanant hold.
for 50.00 bucks I bought one of Estes Astro-Vision digital "READY TO FLY" camear packages. Not expection it to be to much.
what i've discovered is it's a very very nice little 3 pic pre flight camera or 20 sec Video camera combo. with a little be of modification to the booster I'm gonna have all the arial pics I want with NONE extra expense of building one from scratch. Man I've got a lot of unused cameras, transmitters, recievers and junk.. Thanks Estes finally a small inexpensive digital that's worth what your asking for it

 

[..Pat Butler]

I'm really close to buying a FlyCamOne2 for $100. The ground support equipment is just too burdensome for me with a wireless solution. I want to do some fin flutter tests with a camera and don't want to have to lug around my camcorder and power pack.