Hi guys,
I'm building a little ROV that I would like to clean the surface of my yacht's hull and sword with.
It has some serious barnacles, so I'm looking for a high torque servo. Anyone has some experience with those?
Also, I've seen a magnetic crawler in industrial applications. Has anyone ever looked at that for his ROV?
Thanks for your help!
Cheers,
Ken
Waterproof high-torque Servo
Re: Waterproof high-torque Servo
Hi Ken. Considering the cost of slippage and hardstand (and antifoul) building a hull cleaner makes good sense, especially if you have more time than money. I saw one at a boat show that used suction from an impeller or ducted prop to hold it against the bottom, and Bobcat-type tracks to move. The cleaning part of this particular "robot" could have been improved. Really only seemed good for cleaning off slime, new weeds and baby barnacles, at best. I asked the guy at the stand "roughly how much?" and remember it being well over $10K. As for servos or motors you have a wide choice, because the pressure at the bottom of your keel won't be much. Regular shaft seals should work OK. Large stepper motors, geared brush or brushless motors, modified cordless drill.....Keeping the motors cool needs consideration.
Ross
Ross
-
a_shorething
- Posts: 289
- Joined: Sep 10th, 2013, 5:26 pm
- Location: New Jersey Shore
Re: Waterproof high-torque Servo
Interesting puzzle. I assume the cost limitation would be the cost of having a diver do it or hauling the boat and doing it in a sling/cradle/blocks.
One thing I think you'll need to know is what force is going to be needed to remove barnacles in the water. The natural glue they secrete is one of the strongest in nature and the only way I know of to remove barnacles completely is to let them die and dry out over the winter and scrape them off in the spring and that's STILL a difficult job. It takes quite a bit of leverage and force even then. If your ROV can't somehow generate enough force or leverage (or both) to separate a barnacle from the hull underwater, the rest of the design doesn't really matter.
The amount of leverage you'd need to do this while the barnacles are alive, with an ROV/robot hanging upside down on the (presumably) not-so-flat, wet, slimy hull of a boat is daunting to say the least.
It also needs to somehow separate the barnacles from the hull without damaging the gelcoat so it can't be too aggressive either, or else it has to be able to somehow tell the difference between them or be directed from topside somehow.
I can't imagine a device or ROV that would cost less than a few hours of dive time or a two-day haul-out. I would be very interested in seeing it though.
One thing I think you'll need to know is what force is going to be needed to remove barnacles in the water. The natural glue they secrete is one of the strongest in nature and the only way I know of to remove barnacles completely is to let them die and dry out over the winter and scrape them off in the spring and that's STILL a difficult job. It takes quite a bit of leverage and force even then. If your ROV can't somehow generate enough force or leverage (or both) to separate a barnacle from the hull underwater, the rest of the design doesn't really matter.
The amount of leverage you'd need to do this while the barnacles are alive, with an ROV/robot hanging upside down on the (presumably) not-so-flat, wet, slimy hull of a boat is daunting to say the least.
It also needs to somehow separate the barnacles from the hull without damaging the gelcoat so it can't be too aggressive either, or else it has to be able to somehow tell the difference between them or be directed from topside somehow.
I can't imagine a device or ROV that would cost less than a few hours of dive time or a two-day haul-out. I would be very interested in seeing it though.