Acceleration limit of camera? RunCam2 troubles

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Buckeye

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More troubles for me with RunCam2. Tagging @BryRocket, since he is another user.

See attached video that I edited/spliced together for brevity.
  • Liftoff to apogee is fine
  • At drogue deployment (0:11) the color goes wonky, but still recording video and audio
  • At main deployment (0:21) the video freezes, but still records audio until landing (0:56)
I am thinking that the high accelerations at the deployment events were too much for the camera and jostled something loose. Twice.

From my 70G Raven onboard, these are the maximum spikes. Not sure how reliable these single points really are, or if I exceeded the limits of the Raven.

Drogue deployment: 24G axial + 16G lateral = 29G total vector
Main deployment: -64G axial + -30G lateral = 71G total vector

I ground tested the camera at home afterwards, and all seems fine.

This is the second issue I had using this camera in a rocket in 2 flights. Maybe I should try something else.

Any input appreciated. Thanks.

 
The quality of video before failure was nice. I’d personally diagnose what was coming loose and epoxy those connections or components down.
 
It is more likely shock than simple acceleration. A little effort with shock isolation mounting might be all that you need.
 
It is more likely shock than simple acceleration. A little effort with shock isolation mounting might be all that you need.

Yes, shock, (maybe jerk?) is what I getting at with my comments about acceleration. The rapid acceleration fluctuations at drogue and main look similar to your link.

The camera (and altimeter) are rigidly mounted to the sled in the av-bay. Are you suggesting to mount the camera on bumpers, or similar?
 
I saw evidence once in an original Mobius that shocks can be at least a temporary issue for the video. I saw no indication that anything actually came loose or was affected afterwards (camera went on to film other flights without any issues), but a hard landing (drogue-only as the main failed to deploy) once caused the video to freeze while the audio continued. My video is at https://www.youtube.com/ watch?v=RHnot3Zjiww (added space and not linking it to keep the forum from embedding the video), the impact is around 1:39 in the video. But that sounds like a lot of shock during your ejection events, do you use a ton of BP or something? My A3 has never recorded anything close to that on any of my nominal flights.
 
I saw evidence once in an original Mobius that shocks can be at least a temporary issue for the video. I saw no indication that anything actually came loose or was affected afterwards (camera went on to film other flights without any issues), but a hard landing (drogue-only as the main failed to deploy) once caused the video to freeze while the audio continued. My video is at https://www.youtube.com/ watch?v=RHnot3Zjiww (added space and not linking it to keep the forum from embedding the video), the impact is around 1:39 in the video. But that sounds like a lot of shock during your ejection events, do you use a ton of BP or something? My A3 has never recorded anything close to that on any of my nominal flights.

No, not a ton of BP. This is a 2.6" dual deploy, and I use about a gram BP for each event. I do wrap the centrifuge lids with electrical tape to ensure full combustion, especially in cold or at high altitude. Here are the axial and lateral acceleration plots. Not sure how reliable/significant the momentary spikes may be.

lateral.PNG axial.PNG
 
+1 to shock, not really the acceleration. RunCams are made for drones, which definitely have less physical forces exerted upon them than rockets :) Like others have said, epoxy on connections should work along with very secure mounting of all components inside the rocket.

On a different note, which flight computer are you using to provide all those telemetry data points?
 
With some of my cameras, I found that sticking a piece of electrical tape over the top of the card to better hold it in the slot helped prevent botched recordings.
 
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