school science project

[jonnyt]

Hi,
I am looking for advice on my first proper science project. I am planning on having some sort of input device on my room, probably a simple keypad that sends a bluetooth signal when one of the buttons is pressed to a display sign outside my door, so when my parents knock, i can send one of a few set messages/ symbols to them.
I have looked all over the internet for good sites and although I'm not ready to build a robot yet, it's definitely a plan of mine for the future, so I though I'd ask here first. I've read lots of cool articles on simple circuits before posting.

My plan is to attach a small keyboard (5 to 9 buttons) to a microcontroller, which also has a usb output for connecting to my PC for programming, and a digital output to a class2 bluetooth module.
The second piece would be a bluetooth receiver plugged into some sort of display device (an lcd screen/ one of those cool new projection display chips?).
My parents will pay any reasonable amount for the kit I need (as it's for school :-) ) but I don't want to break the bank so any advice on where to order the kit from would be cool.
The main thing I need is the actual details of how to program the thing once i've built it. I think even if i got all the right bits of equipment, I wouldn't know how to tell them what to do - what software I would need.

Does my plan sound possible? Will it be too difficult for someone who hasn't really built anything like this before? Am I on the right site for advice?

Thanks in advance.

[awally88]

I don't know if this will help but this can be done quite simply without blutooth with an Arduino (US $30) and a 16x2 LCD display I have seen a lot of tutorials on the net for this, a quick google search would work!

However if you are looking at using blutooth the Bluesmirf I have heard is quite good, I think arduino has a blutooth shield you can buy for it as well if you wanted to go down this path.  It depends on how much time/money you are willing to spend you can do the first method in a few days for around $50 or spend more time and do something more impressive/expensive. It really depends on you!

What you are suggesting is very possible and quite present on the internet, the Arduino board (or Roboduino as some prefer) I personally feel is excellent for beginners to programming/microcontrollers and quite cheaply priced!

[SmAsH]

how long does the message have to be? with the arduino you could have an led matrix hooked up to a few digital pins and just have some switches that you flick which are connected to an input pin.
for wireless i would have to agree on the bluesmirf connected to the uart pins... but arduino only has one uart and it is used by the usb port,
would it harm the arduino if you used the uart while the usb isn't used?

[jonnyt]

Thanks for the replies. The message will likely only be a single image, ie the words "Keep Out" or a smily face.
I'd like to use bluetooth as I'd get higher marks for using more complicated technology, it won't need wires and I may even be able to expand the project next simester to be able to send images from my phone.

[SmAsH]

well, you *could* do that with a transistor and a string of leds or similar.
if you want it to be customizable i would go for a matrix or a 16x2 as awally88 mentioned but the led matrix would be prettier!

[jamort]

the funny thing about this is i think that what you are explaining can be done on a computer with monitor hanging on the door and a keyboard or you purchase a keypad and have the code running off the computer... just advice... you may have to use a microcontroller.

[Soeren]

Hi,

I am looking for advice on my first proper science project. [...] The main thing I need is the actual details of how to program the thing once i've built it. I think even if i got all the right bits of equipment, I wouldn't know how to tell them what to do [...]

I'd like to use bluetooth as I'd get higher marks for using more complicated technology, [...]

So, in other words, you want other people to hand you the higher marks?
Perhaps you should stick to something that you actually have a chance to do, or to learn to do, in the time you have for it.

[SmAsH]

I'd get higher marks for using more complicated technology

but you will get lower marks for failing...
don't attempt a project that is way too hard.
make sure you do research okay? its the most important part!

[jamort]

I would build somehting that I know would get me a grade then start something completely seperate that is more complicated

[paulstreats]

I'd like to use bluetooth as I'd get higher marks for using more complicated technology

I would have thought that you would get better marks by using a simple technology but being able to demonstrate and report on its functionality accurately.

Things like bluetooth are just built ontop of basic technology - considered higher level. the main achievement of bluetooth is in its stacking system but this isnt really a technology rather an organisational system (and that often fails).

Demonstrating something that can be achieved easily (like just connecting a pc monitor to the door) would show that you know the best way to accomplish a task(things like bluetooth woud overcomplicate the situation aswell as adding more cost to it).

Also at some point you would more than likely have to try to interface a bluetooth device to a microcontroller (using a very high level device with a very low level device / language will be very complex from a software point of view)