Help With Hydrodynamics

OK, so this question might be difficult and it's definitely self serving, but I figured if anyone knew, it'd be the brain trust present here.

I've been brainstorming on how I'm going to rig my GoPro to capture underwater footage when I go fishing. Obviously, I can't be down there holding the thing, so I need to make some sort of contraption to hold it for me. While I could easily make a sort of landing craft to just drop it on the bottom and have it sit nicely, it would then have to be attached to the boat, much like an anchor. And as any anchor boy knows, fishing next to an anchor is a pain as the fish bolts and gets all wrapped up in the line.

So what I wanted to do was have it suspended off the bottom, attached and hung off the stern. I usually fish in 25'-30' of water, and don't have a pole that long. That means I'll have to use a line of some sort. My problem is that my boat is only anchored at the bow, and as such, waggles back and forth a bunch due to wind. It doesn't move quickly, I'm talking fractions of a knot, but it moves far, probably in excess of 30' back and forth. As anyone who has ever pulled anything through the water fastened at one point knows, things pulled through the water in that fashion have a tendency to spin. I want to eliminate that. I want to keep the camera as steady as possible.

So what we're looking at is a camera in water, supported by rope, that's going to rise and fall about 2' per 3 seconds due to waves, and that will be pulled one way for ~10' per minute for 3 minutes before reversing course and being pulled back the other way. I understand that everytime the direction changes left to right it may spin, and that's fine. I just don't want it to spin uncontrolably the entire time it's in the water.

I've only had two ideas so far. Both involve making a square out of 1/8" steel plate, perhaps 9" long and 1" wide. Just an easy little square that I could fasten the camera into. I first though that all I needed to do is attach some ribbon or cloth to one side, thereby having the extra drag act like fletching on an arrow, keeping it straight. My problem with that the ribbon would be a lot of movement, and I don't want that right where I'm fishing. I'd also worry that I'm not moving fast enought for that to have an effect. My other idea was to fashion the square non-uniformly. If I made one "wall" only 1/2" wide while making the other wall 3" wide, I though it might have the same effect as, say, a weathervane, with the wide side creating more drag and thus keeping it steady. But again, I'm not entirely sure if I'll be moving side to side fast enough, and I don't know how the up and down movement of the waves is going to affect this.

Anyone want to help me brainstorm on this, or have some input on the above uneducated guesses?

How about dropping off so it lands on the bottom of the lake and rises with positive bouyancy to the surface, you then add just enough ballast and take in just enough line to keep it down where you want it?

How about a motorized stationary platform rather than an anchor line of any sort.

Quote: Fleastiff

How about dropping off so it lands on the bottom of the lake and rises with positive bouyancy to the surface, you then add just enough ballast and take in just enough line to keep it down where you want it?

I'm not sure you're getting what I'm asking. I can "get it where I want it". It'll be in a very heavy frame hanging from a rope off the stern of my boat. I can drop it until it hits bottom and then reel it in a tiny bit so it's suspended just off the floor of the lake. That's no problem. The problem is that my boat drifts back and forth due to the wind. My camera will obviously move with it. My fear is that this movement through the water will cause the camera to spin constantly and uncontrolably, since it is just dangling by a single line. I'm trying to figure out a way to give it some stability so it can move through the water without doing so.

Quote: FleaStiff

How about a motorized stationary platform rather than an anchor line of any sort.

Like a remote controlled submarine? =D That'd be some fun, for sure. I just don't have the funds to dump into one.

Quote: Face

I'm not sure you're getting what I'm asking. I can "get it where I want it". It'll be in a very heavy frame hanging from a rope off the stern of my boat. I can drop it until it hits bottom and then reel it in a tiny bit so it's suspended just off the floor of the lake. That's no problem. The problem is that my boat drifts back and forth due to the wind. My camera will obviously move with it. My fear is that this movement through the water will cause the camera to spin constantly and uncontrolably, since it is just dangling by a single line. I'm trying to figure out a way to give it some stability so it can move through the water without doing so..

Attach the line to some fishing bobbers and go retrieve it when you're ready to bring it up. (they will be visible on the surface)

Before attaching the camera to any contraption, I would test a dummy version. Make sure you don't have an expensive failure!

Something with long spiked (wire coat hanger thickness) may help secure it from rotating as they can stick in the bottom.

3 Tripod, or maybe quad legs. Kind of stab the bottom to anchor.

By creating something with some air and water (milk jug) you can also neutralize the weight. It won't sink like lead, but will have neutral weight. I think similar to scuba divers. It can go up or down easily, because it will have some buoyancy.

Just for fun....the boat always drifts back on the bow anchor. The weight will keep the rig down, and pointed in the same direction. Only 1 line in the water.

Quote: beachbumbabs

Just for fun....the boat always drifts back on the bow anchor. The weight will keep the rig down, and pointed in the same direction. Only 1 line in the water.

THIS.

OK, you get it. The stiff wire will prevent twisting, and the geometry will prevent the swaying. Babs, you nailed it =)

Of course, I want it off the back and not the anchor so I can try to capture images of the fish striking, but I'm relatively certain I can recreate this same setup off the rear.

You also nailed the boat. Colors aside, it's a direct representation. You been spying on me? ;)

Quote: Face

Quote: beachbumbabs

Just for fun....the boat always drifts back on the bow anchor. The weight will keep the rig down, and pointed in the same direction. Only 1 line in the water.

THIS.

OK, you get it. The stiff wire will prevent twisting, and the geometry will prevent the swaying. Babs, you nailed it =)

Of course, I want it off the back and not the anchor so I can try to capture images of the fish striking, but I'm relatively certain I can recreate this same setup off the rear.

You also nailed the boat. Colors aside, it's a direct representation. You been spying on me? ;)

Glad it might suit; was a fun mental exercise. The steadiness depends on the rope being at an angle, not directly under the boat; the collars should allow the rig to swivel around the rope as it goes down, then steady out and hang from the rope.

Haven't been spying, but I'm missing my 15' flats boat w/ Honda 4stroke 45. It was perfect for the shallows of Intercoastal Florida. I was very, very broke the last couple years, and sold it. Something about getting out on the open water that's healing, and resets your mental clock off of fast.