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  • Garry Qualls June 19, 2010 at 8:58pm
    Even with all the high-tech, high-rate servo compensation, they still sometimes run video frame stabilization in an onboard graphics card where they shift each frame of video in real-time to make it smoother and easier to watch. Basically you can take something like this:

    https://www.youtube.com/watch?v=TSItWT2PrP0

    and turn it into this:

    https://www.youtube.com/watch?v=mnDIrkxaxNc

    ...before you broadcast it to the ground. The more you want to zoom in, the more tricks you have to use, of course.

    They also have to solve all these problems when they film sequences for movies from helicopters, boats, etc. On those systems, and on many steady-cam rigs, they will attach gyros to greatly increase the rotational inertia of a gimballed camera. Not gyro sensors like the ones usually discussed here, but flywheels spinning at around 22,000 rpm so that you can't hear them. The brochures say it takes them 10 minutes to spin up to full speed and 15 minutes to spin back down when you turn them off.
  • Admin
    Morli June 18, 2010 at 2:11pm
    Yep , no weight up there that has no reason to fly.Every thing is stripped to bare essentials as one would notice in the camera pod( yes it is Sony 27 X block camera stripped of almost every thing). Every thing is hollow light weight material without compromising the integrity. I doubt if steady cam or any passive Cam stabilization system can live with that( no counter weights). But still interested/ing to hear experts in this field.
  • Moderator
    Gary Mortimer June 18, 2010 at 1:31pm
    Never add weight to an airframe unless it has a use. The Scaneagle is an excellent example of revolution and evolution.
  • Admin
    Morli June 18, 2010 at 1:03pm
    Yep , the problem needs to addressed from two directions as seen in this photos( thanks Leno). there is lot more technology( both active and passive in there) Both Source and destination of vibrations. Here is what you can see some times in small prof grade UAVs.

    But what you don't get to see ( usually ) is this. Problem is mitigated at source here.

    the gimal is also mounted on 3 point mount with dampers here. Will be very interesting to see if any one can figure out less complex passive method like steady cam for such usage. BTW counter weights are dead weight but we can live with it if that will save few K$.

  • Overwatch June 18, 2010 at 12:34pm
    That's a passive low-frequency stabilizer, these don't work at all when flying, since the down vector changes a lot. Standard active (servo) stabilizers have already reached near perfection (and they don't need a heavy counterweight), it's the high frequency vibrations that still cause problems.
  • Mauro Rodriguez June 18, 2010 at 12:21pm
    Watch this videos...
    https://www.youtube.com/watch?v=1Cs8B_EW3aI&feature=channel
    https://www.youtube.com/watch?v=sMSuJ4d89OE&feature=channel
    https://www.youtube.com/watch?v=U5EL-y5NEuQ&feature=related

    A problem that I see is to change to a desired direction...
  • Admin
    Morli June 18, 2010 at 12:19pm
    the biggest problem for camera usage in aerial vehicles is its stabilization problem in high freq vibration( comparatively) . Human body's natural ability to balance( with in built all axis gyro), guide( to point of interest) and soften/dampen the vibration helps a lot to make steady cam work IMHO. this is a great article which I saw earlier while thinking about the problem. But I am not sure if this tech can be practically used in UAVs in particular. Single point mount in this mechanism is sort of tricky thing to tackle in UAV since there is no hands to guide the camera and most often centrifugal forces in other axis come into play while flying unlike when held by humans while doing a walking or running shots. what do you think? Lets also hear from other who know more about these things.
  • Komugi June 18, 2010 at 12:16pm
    Centrifugal force will cause it unstable..and swing all the time.
  • Mauro Rodriguez June 18, 2010 at 12:00pm
    Maybe to help the stabilization of the camera????? What do you think?
  • Admin
    Morli June 18, 2010 at 11:55am
    Where in UAV or any aerial application would you think this can be used? thanks for sharing the info and link.
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