

Sep 29, 2005, 11:30 AM  
Sunland, CA
Joined Jan 2003
27 Posts

Quote:
for being a father of three kids, it's been tough to find time to do a project. my turtle ship is about 90% complete, but now i'm taking a break. my fivemonth old daughter needs me... i'll have to build a whole new one with bottom heavier than the top. currently, all wood pieces i used are 1/8 inch, so when the ship is in water, it does not stand straight. so i'll use this one as just a model and build another one with more balance in weight distribution so that i could use it for RC. thanks. 

Sep 29, 2005, 12:15 PM  

If you fold a piece of cardboard, or take one of you model oars, and hold it at the piviot point, I think you will find that a circular motion at the end of the "L" will create the skulling motion that is needed.
Imagine a linear set up of "circles" much like steam locomotive drive wheels. With the handle of the oar at the back of the "inscribed" circle, zero, the leading edge of the oar will be angled in toward the boat. Lifting the handle along that circle, to 90, will skull the oar in. Pushing it forward along the circle, to 180, will angle the leading edge of the oar out away from the boat. And driving the handle down along the circle, to 270, will push the oar out. And pulling the handle back zero will angle the oar for another inward stroke. The Pivot point is where the design is a bit rough at this point, it will need to gimble in three dimensions. 
Sep 29, 2005, 01:00 PM  
Sunland, CA
Joined Jan 2003
27 Posts

my idea of how it works
thanks Umi,
i don't know if i understood you right, but just by moving the oars back and forth does not create propelling force. at the end of each round, the oar has to tilt a bit and change directions from inside out and outside in  i don't know if i make myself clear. so here's my thought. the problem i found was that i had to create three pivots including one attached to the bar (thick black colored), and there are 16 oars. 16x3=48 pivots... lot of work... and they need to move not only back and forth but also a bit up and down as well... anyways... 
Sep 29, 2005, 01:16 PM  

I think that I have the motor turned 90 degrees from what you are proposing.
Your motor positon pushes the oars in and out. My proposal points the motor perpendicular to the centrline of the boat. The "┐" handle portion is also perpendicular to the centerline of the boat. The inscribed circles of each oar would be parallel to the centerline of the boat. The lever action on the pivot point forces the oar to move in and out at the top and bottom of the circle. Pushing the the handle of the oar to the front and back of the circle changes the angle of the oar as it moves either in or out. Don't make me build a mock up... 
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