First of all, let me say that it's great that you and your partner are getting a 2 year head start on this! If you both work diligently and effectively on this project together, you will produce something great for the ISEF.
I have a lot of information for you, so this post is very long. I hope you find it all useful!
I was a participant in the 2007 ISEF, so I will offer my advice based on my experience. My project involved finding the most efficient wing design for an airplane by testing one design parameter as the independent variable, leaving all others controlled. In short mine was an efficiency project--considered an engineering project, because it did not ask a "what if I do this?" sort of science question, but rather a "how can I improve a design to make it more efficient?" sort of engineering question.
Now, I did not do a robotics project, but I will still help as much as I can.
Your project sounds great--but I do have some advice for you. To go to ISEF, you need to do more than build a cool flying machine from scratch. You'll need to take it a step or two further--build a machine, and then determine how you can improve the design and make it more efficient. ISEF is a Science and Engineering fair, so you have to ask yourself: is this science or engineering? The science of quadrotor technology is already established--the physics of flight using four propellers. So, I would say that you should say it's an engineering project--robotics, yes, but engineering in that it seeks to improve a design so that it can more efficiently perform tasks.
Judges are looking for new ideas, new information, and new contribution to the scientific/engineering community. If you build a cool quadrotor, you may impress a few but you will be much more impressive, and have much more scientific/engineering weight if you build a cool quadrotor that is better than others in ways that you can clearly explain and demonstrate.
You mentioned that there is a non-WiFi quadrotor on the market. It would be a good idea to start from there--I suggest that you buy that quadrotor (if it's in your budget), and play around with it to study how it works. Base your design off of that one, including your WiFi component, and see if you can improve on the design and make yours better.
You must choose how to define "better." Do you mean to say that it can fly further, or higher, or that it can lift more weight? You must choose some number of criteria which you will use as your design parameters, measure the performance of the first quadrotor (the one on the market, or if you don't want to buy that one that you build first) in terms of those parameters, and then improve on the design to see if you can increase the efficiency of the performance based on the parameters. For a very simple example, get the market quadrotor and see what it's maximum weight capacity is for vertical take-off--hang a payload on it, increasing the weight for each successive trial until it cannot lift it anymore, and record that weight. Then, attempt to improve upon the design with your WiFi model, and see if it can match that weight, and surpass it.
Once you have improved on a design parameter, the next step should be to see if you can improve even further, and maximize your efficiency with your given materials, budget, etc. Naturally this will take a lot of research, and a lot of testing on your part, but you have 2 years to make this good so I think you two have a great advantage!
Now, it is VERY important that you choose GOOD DESIGN PARAMETERS--these will be key components of your project! Judges want to see that you have chosen useful, practical parameters for your experiments, so that you are contributing to the scientific/engineering community in a meaningful way. I strongly suggest that you base your decision of parameters on modern practical applications--such as public transportation, and military application. For simple examples, see how much weight it can carry (public transportation), and see if it can be highly maneuverable (military application). Definitely do research to see if quadrotors have been tested or are being tested by the military or by companies such as Lockheed, and see if they have had problems. If you can back up your choice of parameters to test with real-world research results from respectable sources, you will impress judges.
It might be tough to find information on quadrotor testing. I'm not sure if it's been done, I simply suggest that you look. If you cannot find it, I would base my research on helicopters instead. Also, I would make sure that I would communicate the advantages of quadrotor technology over helicopter, if there are any.So basically to summarize, I suggest that you work to improve designs and show a progression of improvement with multiple designs based on one beginning design, like the market quadrotor. I suggest that your improvements be based upon meaningful, practical applications in real-world situations based on research. Don't choose too many, but I would definitely go for more than one. Finally, use your time to test design changes and see if you can maximize the efficiency and performance of your design based on those parameters. This is what will impress judges! Judges want to see that you have taken something useful, made it more useful for today's world, and can prove it with data and explanation.
Since you have 2 years, I suggest that you try to get into ISEF both years--you of course need to compete at a lower level in order to get to ISEF, so that first year's competitions will help you see if you are on the right track. You can get very useful feedback from judges at lower levels, and you can also get some meaningful experience and practice with presenting your project. You may even get into ISEF 2011! If you do, that would be excellent--you'd get a great deal of experience, practice, and advice. ISEF allows continuation projects from previous years, so if you got into ISEF 2011, then you'd be able to continue your project throughout the next year and try again for ISEF 2012--I strongly suggest that you do this! You have 2 years to get this project done, but it would be much better to start presenting what you have in 2011 than to stay in your lab for 2 years and only come out for 2012. Does that make sense? Make use of your time--you have a TON of it--to do a good project, AND to prepare for ISEF 2012 by practicing in lower fairs in 2011.
Now, I'd like to provide you with several helpful links. First off, Science Buddies provides this resource regarding the Engineering Method, based on ISEF's guidelines:http://www.sciencebuddies.org/science-f ... ring.shtml
All ISEF guidelines and rules may be found at this link, on the official web site of Society for Science and the Public, the ISEF organization:http://www.societyforscience.org/isef/documentThis next resource is VERY helpful--I STRONGLY suggest that you explore it.
It is ISEF's own abstract search engine. Abstracts are the one-page explanations of a science/engineering project that every ISEF participant must submit. If you use the search engine to find award-winning projects from past ISEF's and search for "robotics," you will find very helpful information on which you can base your project. My advice will prove helpful, but I did not do a robotics project, so it would be very helpful to check on past robotics projects and see how winners did it. For the search parameters, I suggest that you select all ISEFs, and leave all other search categories blank except "keyword," which should be "robotics." Then select "Only Winning Abstracts," and you will see a great deal of helpful abstracts from the past. You can search beyond my recommendation as well--see what you can find! https://apps.societyforscience.org/abstracts/
Also, be sure you use Ask an Expert if/when you run into problems!
You may also find it helpful to read Science Buddies' ISEF Blog, written by the daughter of our founder, who has great ISEF experience:http://www.sciencebuddies.org/science-f ... isef.shtml
I think that your project could be very very impressive, and again it's great that you two have so much time to work on it. I know that high school can be demanding so it's not like you have 24 straight months to devote entirely to this project, but still it's very advantageous that you have the opportunity to work for so long, and to practice in 2011 fairs. Make sure that you do good research, make meaningful design change choices, and keep in mind that you are trying to contribute to the modern understanding of quadrotor technology and what it can do for the world.
I wish you two good luck, and please feel free to ask me more questions if you wish!