I had an idea with a friend about having miniature naval battles with balsa wood or thin plastic model boats that are radio controlled.
The idea is to make basic boats out of light and somewhat fragile parts that you could install a remote controlled motor in so the would function the same as regular remote controlled boats. But, there would be a second part, a remote controlled gun, that would be used to literally shoot the other ships and sink them. All electronic parts would be sealed in a sturdy, waterproof box so if your ship is sunk, you could retrieve the parts and rebuild.
My question is primarily about this gun. I would like to have the gun mounted on the front of the ship, be able to change its angle up and down (and maybe a bit side to side), fire from the press of a button, and auto-reload itself (some sort of clip). I would think the best would be to have it powered by C02 since it is easy to get and it should shoot standard pellets but with enough force to pierce thin plastic or thin wood.
My initial idea was to use a small Arduino (Micro or Mini) with a bluetooth shield and a small bluetooth camera that would be controlled from an iPhone/Android app so on your phone you would see the camera feed and be able to fire and move the gun from the app.
How feesable is this? What sort of issues would I be looking at and what type of motors, parts, etc could be recommended? What could I use to auto-load the gun and how could I fire it using the Arduino as the trigger?
It would need to be extremely fragile to be able to be destroyed by something that was safe to use around humans - maybe use one of the construction techniques used for model aircraft, such as varnished tissue paper?
I suspect the best approach would be to have a fairly substantial main body that has all the working parts attached and is designed to be very slightly negatively buoyant, with an upper hull that is essentially just a low wall which just has to keep the water out and provides the tiny extra amount of bouyancy needed to keep the whole thing afloat. It could be sunk either by swamping it with near misses, or by hits near the water line which introduced leaks. It would be a bit like the ill-fated Duplex Drive tanks used during the Normandy landings - barely floating and easy to sink.
I would think the best would be to have it powered by C02 since it is easy to get and it should shoot standard pellets but with enough force to pierce thin plastic or thin wood.
I would consider Airsoft as it is cheap and easily available.
You may wish to consider foam-filled targets that are held together by magnets... Even those rubber ones. A well placed hit would separate the pieces but no major damage.
For the Airsoft equipped gunboats, I would use multiple piezo sensors in strategic locations to measure impact energy. You could also use magnetic contact switches in "repel" configuration... A well-placed hit closes a contact. By using scoring per strategic hit, the gunboat's can automatically tally their damage and shutdown when the battleship is sunk.
I agree with Ray.
Why do you actually need to destroy the boats? I mean that leaves a lot of things to chance. What if you get a perfect hit and still it doesn't do the expected damage due to just variation in the assemblage or just sheer luck. More definitive and fair way to play the game would be to have the destruction mechanism also built into the ships, based on some sensors. You detect the hit and execute the damage on the receiving end. Heck.. in that case you don't even need the actual projectiles. They are symbolic.
Granted that this is not exactly mimicking real life... and there is a definite "charm" in seeing the boats being actually destroyed by the hits .... but this is still a huge step more realistic from the XBox/PS3 video games! And also lot simpler to build.
As for the guns, you can easily put in some servo motors and build a couple of hinges/gear mechanism to move the gun up/down/side to side.
In reality I feel it would be very challenging to execute a hit on tiny moving boats using a projectile from a remote control gun. You may soon find that the shooter needs some sort of smarter tracking aid in executing the shooting.
I agree with the idea of having sensors register the hits (focused IR beams with a prefix to the "shot" to identify who shot what, where) but its just not as fun. On actual battle ships and tanks from WW2 sometimes the shells would just bounce off due to sheer luck so this is something that would be somewhat of a bonus.
I like PeterH's idea and with that you could easily get sunk, grab your boat out of the water, and just put a new cover on it. In the end, 2 versions of this hull could be built - a strong one with sensors and a paper-ish one that just tears apart. Depending on your desired gameplay, you just put the appropriate hub on.
I have seen some of the videos about building large, hand-held airguns but I have some trouble coming up with a way to miniaturize it. What could be some tricks to miniaturize it? Also, are there any good tutorials for building a turret like this since I have never actually worked with motors before so much of this is new to me.
Mechanically you are trying to achieve something on the lines of this;
You can get small servo motors and experiment with code to learn how to operate them.
Instead of a gun how about a Katusha rocket launcher, but firing small rockets one at a time? You would not need to destroy the other ship, just score a hit. Pretty hard to aim but it might look quite impressive.
The practical problems will be keeping motors dry and handling recoil. I guess you would have to come up with a gun turret and then design the ship round that.
The rocket launcher with bottle rockets would be really really cool but a bit too much at the moment.
I will take a look at that servo mount and recommended motors - it looks promising.
I am going to build the turret first and then design the boat around it. As for waterproofing, I figure I can do something similar to how it is in real life - have all the hardware in a box and have the barrel stick out of a bag-style thing.
For aiming, what I want is to have a small camera that can send the image over bluetooth to something like an iPad. Then the iPad app would have a few buttons for moving the turret and firing. What equipment would be good for such a thing or is that asking too much from an Arduino (bluetooth video and data link for controlling the servos)?
radman:
How about a wifi camera, would that have the range and be cheap enough to feed directly to the iPAD?
Regarding gun turret control this type of thing must have been done with RF models before, is there any particular reason for going the arduino route?
A wifi camera would be fine (it doesn't have to be a great camera, just basic) but how would I get that signal on an iPad?
As for the Arduino route, it is the only one I know. I never messed with RF models before so I just figured if I had an Arduino with a cheap bluetooth shield I could plug in the camera and be able to send the commands all from the pad. This would give me the ability to also control steering and everything from the iPad with the live feed on it or have teams of people, one who controls the ship and the other who is the gunner.
The simplest thing would be to have a camera that acts as a wireless access point then you would get the iPad to connect to it as normal.
There may be ways to setup a point-to-point link between an iPad and the camera, but I am not sure about that.
There will be a whole world of people out there that have built radio controlled battleships etc. You might chose to do it using an Arduino but you should look at how they have tackled problems first.
