this is a ters

Discussion in 'Boat Design' started by inventured, Sep 16, 2015.

  1. inventured
    Joined: Sep 2015
    Posts: 5
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    Location: BC

    inventured Junior Member

    Hi Everyone! :) Don't ask me why the title is what it is, or why my youtube embed's don't work. What's important is, I cant fix it, because im dumb I guess. Anyway...

    I just joined up here a few days ago because I was seeking info on another topic. Since I'm here now, I thought it would be a good opportunity to bounce an idea off you fine folks and see what everyone thinks.
    The topic: Motion Sickness - The Satan of the Seas.
    No, just kidding (sort of)
    First, please watch this:

    This thing blew my mind when I first saw it. I started thinking about things like:
    If I sat on this table, would it feel like I'm sitting on land?
    Why didn't they build it so the table sat on a floor that reacted like this, so the players wouldn't be moving around?
    And most important: Why not make the whole boat do this!
    So, I did some research. The creators of the table weren't spilling it secrets online, so I looked into how things can be "stabilized" like this, and that search led me to this thread: ( and here is a pic & quote from it:


    09-23-2011, 07:44 AM
    This concept was tried on an English Channel Ferry back in the 1800's.

    The large 'main cabin' was suspended on bearings, so that it could remain vertical, even if the rest of the boat was rolling.

    The 'cabin', developed its own momentum, and swung back and forth independently of the boats main hull, flinging the passengers around wildly.

    They tried the trip a second time, with a 'brake-man' who could apply a damping system to this pendulum effect of the main cabin.

    Unfortunately, it wasn't able to be controlled sufficiently, and the boat was converted to a standard ferry.

    If you build a scale model, I suspect you will find that the central 'pod' will develop its own momentum, which will be much wilder and more uncomfortable than that of the boat itself.

    The Next Best Thing: SEA-KEEPER


    Some of you know what a Seakeeper is, but for those that don't - Its a gyroscope that spins in a ball and you put it on your boat and it very successfully dampens the roll: This video will blow your mind:

    So now at this point, i don't really care how the pool table works. All i can think about is my idea. so here it is, finally
    What do you think would have happened if we put a Seekeaper on that old English Channel ferry? Instead of countering the roll forces from the water, wouldn't it counter the momentum that occurred instead? I would think movement resulting from that would be only a small fraction of what the Seakeeper would normally dampen. But what if someone walked across deck? Would a large enough gyro inside a gimbal like this compensate for that also? This is where my brain starts to hurt. The only way to remove the headache is to either find someone smarter than me to explain the dynamics of this, or to build it.
    And I am TOTALLY going to DO IT... as soon as I win the lotto. I get all the negatives that would come with a ship like this. it would need an overly elaborate and expensive way of locking itself back into normal or else it would be near impossible to board it with the sides of the hull moving and the deck not. But I was thinking I could build a micro sized version, and then see for myself what it would do. The gyro that is used in that boat in the Seakeeper vid is online here:
    If i had one of these, and a gimbal hull similar to this (sort of):
    All combined into something like this: then... Test On!
    Now, before I go designing this in my mind, I want to figure out another idea that came to mind while thinking about all this.


    Lets take it one step further, even if its not possible.

    When the ocean rocks my boat port to starboard, and the gyro causes the gimbal to compensate, The hull will move but the gimbal won't. So what if there was a bearing of some kind between the inside of the outer hull and the outside of the gimbal. could that bearing connect to a small alternator (or 20 of them) and generate power? Maybe even enough to half power the Seakeeper?

    What do you guys think? Is it worth the few hundred bucks to build a prototype and see what happens?
  2. Rurudyne
    Joined: Mar 2014
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    Location: North Texas

    Rurudyne Senior Member

    Interestingly, in tall buildings they use the opposite: the pendulum that reacts to movement is sufficiently massive and high enough to dampen same in the rest of the structure. The trick there is not control over the pendulum but limited range of motion.
  3. SamSam
    Joined: Feb 2005
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    Location: Coastal Georgia

    SamSam Senior Member

    It seems like it would shift the center of gravity (or some such nautical term) of all that weight up to the pivot point, which might not be good.
    Getting into it at a dock, like a ferry boat would be, would be one thing and getting into it at sea, with the hull and the pod going at wildly different rates and directions, seems like it could be tricky. Possibly fatal.

  4. whitepointer23

    whitepointer23 Previous Member

    I love the deck moving beneath my feet. There is nothing like it. I would not want to prevent a boat from moving how it was designed to. If you want more stability buy a cat.
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