Could not complete my project on ships

[arfat.salman]

hi every one
I'm new here so i am confused as to where to post this topic but i guess this is the right place.

I am having a science project in my school and I am building a ship that could go a particular distance and return to the same spot again.There are restrictions that I cannot use combustion engines, pressurized fluids or any thing like that. Only a battery and motor( no size restriction on battery).


It will be like any normal ship except that both sides will be symmetrical because I am thinking of using an H-bridge to reverse the polarity of the motor.

Problems faced:

1. Can i use breadboard to mount microprocessors and do some coding to make the H-bridge automatically change polarity after specific time.

2. I want the ship to change polarity after , say striking a wall. Can I Use any kind of sensors like IR-LED for that or in more general way how do I make the MC decide when to change polarity.

3. Can I any how increase the speed without increasing the battery power and assuming that more battery power means increased battery weight, i don't want my ship to be very much heavy.

4. I'm thinking of using two motors with propeller. What do you think how many motor should I use.

The ship is not remote-controlled.Once started it has to it has to do everything on its own(going and returning). It has to compete with other ship made by other students so it has to pretty fast.

i am in high school and and if i win the race i might get A grade in my Extra-curriculars.

Please tell how can i make it more better.
http://imageshack.us/photo/my-images/851/shipmodel.gif/
here my blue-print..i know its silly but i think it conveys the idea pretty fairly.

 

[mjpaige21]

Your criteria are somewhat vague.
You stated that it must "go a particular distance and return to the same spot again." does this mean return to the "spot" it originated from, or the "spot" it arrived at after going "a particular distance"?
Unless you are to include some type of inertial guidance, there must be some external reference point to determine where it is "now" and where it is "Later".
Does the travel there and back have to contend with wind or waves, or other external forces? (It is a ship)
If the task is to return to the point of origin, AND a reference point is acceptable at the point of origin (Like a lighthouse, but in miniature), your ship "merely" has to "home-in" on the light.
If the ship has to return to a point out in its "Ocean" then two reference points are needed (lights, or beacons)
Should all of the above be acceptable to the "rules", then a circuit similar to those used to "point" a solar collector at the moving sun would be a likely choice. There a lot of very simple circuits on the internet using photo cells and an OpAmp that would serve this function to control the speed of two motors that would effectively keep the ship pointed at its beacon without a rudder. A more complicated arrangement with two ground side beacons would work to return to a point out in the "Ocean" and if further modified could actually do "Station Keeping"

If the above is not acceptable to the "rules" then some form of inertial guidance is required. That is considerably more difficult.

There is another option (if acceptable) train a pigeon to "operate" the controls. Look up experiments with pigeons to help search for victims lost in the ocean. Before computers there was a proposed way that trained pigeons could find and direct their transport (say a helicopter) without the use of a computer. Look 'way back, say in the 1950's 0r 60's.

I also remember one where an experiment using a grasshopper was used to "stear" a plane (or possibly a ship) around obstacles. I don't think it had "homing" capabilities though. It was mainly for "crash" avoidance.