Ok here it is a odd question I know but here it is. Of course I know I need electric power to run my ships electric components but what I am wondering is can I do it with out a huge battery, most people would say no it cant be done. I have found something called a over unity motor, what is a over unity motor you may be asking well lets a say 6v electric motor turning a 9-18v motor which while second motor is the generator with say a small rechargeable battery or capacitor to keep a charge to keep the system running. I have tried it, it ran for over a hour before I unplugged it. Longer then just a battery turning a motor which would run say 30 mins max. I was wondering on this matter if any one would like to try this and let me know what they thought of the idea and there are lots of you tube videos on saving energy granted there allot of crack pots out there trying to trick people but I have made it work with just 2x 6v motor set up although it had slowed down over the hour it was still running. I am designing my first ship and am going to try some new ideas with my first build.
I will ignore the issue on whether it is more efficient (it isn't) and go to the practical matter (this is assuming that you don't take my word for the efficiency, and I'm cool with that)... The second motor being used as a generator would need an amp rating as a generator high enough to supply all the other motors on the ship. Once that is acheived (big generator (in our scale)), it wold be a very poor generator under changing loads because its brushes are set to commutate in the neutral plane as a motor would find it, not as a generator. Commutating out of the neutral plane means that the commutator is not breaking the circuit where there is essentially no current flow through the brushes, but instead where there's a pretty good bit of current flowing through them. This dramatically increases brush wear, and damages the commutator surfaces. Very short operational life, and it's not really easy to adjust the brush rigging on a motor so that it's a good generator on a motor as small as the ones we're using. Next problem would be putting a circuit on the output of the generator to clean up the power coming from the motor-cum-generator, reducing spikes, low points, etc. If you run an ESC for your drive motor, they will NOT like dirty power. Best suggestion: go with a good battery. It doesn't have to be huge, and it's a LOT less complicated. 12AH at 6V will do just about any battlecruiser, and a good number of battleships. Fast battleships or really powerful pumps (not always a good thing) could demand two such batteries. Trying new ideas = good, with the proviso that not all new ideas are things that you want to try
No. Enough things on our boats are failure points, overcomplicating just leads to more potential failure. Also if you have waste power such that you could recover some of it and put it back into the system, you would be better served by selecting a more appropriate motor / gearing / prop combination than trying to rig together an energy recovery system.
Another point is that many many ships require weight to float near a semi-scale/scale waterline. May as well use battery weight (more capacity) instead of dead weight that does nothing but just sit there.
I would tend to agree with everyone else here. I have built two wooden hulls with added ballast sealed in the bottom of the hull. One worked out fine, but in the other, I over-estimated, and ended up with a boat that had a little too much weight in the stern. I would suggest going with the larger battery, in the middle of the ship for simplicity, to help keep your center of gravity positioned for better manoeuvrability, it inherent higher capacity, and the added fact that it is modular in nature--it can be swapped out if you find something else you want to try.
I've been using LiPOs for years. No explosions. I promise. I get them from either HobbyKing or HobbyPartz.com, whichever is cheaper for what I'm looking for. I buy the 30C ones, we don't really need 45 or 50C batteries. One 8AH 2S LiPO went 5 sorties at Nats 2012*, running and pumping the whole time. Didn't even get warm. *in my armored cruiser in the middle of the enemy fleet for them ost part
