Need advice to choose components for a project

[Lelan]

Good morning everybody !

First of all, thank you for having created this forum very helpful
I'm contacting you because I have a technical question for a project and I thought you could help (hoping I am in the right section!)

I'm searching for electronic components which would be used in 2 different devices. The component of one device should be able to signal its presence (via radio, IR, Bluetooth...) to the other device when both are using a compatible "frequency" (or compatible information, message, algorithm, or whatever it can be) and when they are near one to the other (5 or 10m maximum is enough). If both devices are "compatible"in terms of "frequency", both would emit a signal (led or vibration).

I guess transceivers are one option but maybe RFID readers/writers or bluetooth system could be options as well.

I only would like to know which technology would be the best to use to achieve this project ? (because then I would have to really learn all about this technology to do it^^)

The constraints are:
- I'm looking for chips/components which work in a standalone mode (with battery).
- Each one has to be able to send and to receive information
- The components should be as small as possible (1 to 3 cm if possible)
- Ideally, we should be able to configure the "frequency" (or the coded message, or..) of each device easily, from a PC (only to be configured one time): for example through a dedicated program connected to the chip via micro USB.

To resume, I would like a little device able to permanently scan the presence of all the possible other devices around it (10m), while the others make the same, and when 2 devices detect the presence of each other, I would like them to be able to connect one to the other and verify if the frequency/information/coded message is compatible one with the other. If it is the case : led goes ON on both of the devices. If not : nothing happen, and scan can continue.

Can you give me your advice on which technology would be the best ?

Thanks a lot for in advance !
Have a nice day !

 

[Fish4Fun]

You have basically outlined:

Bluetooth
RFID
and portions of the ISO7816 smart-card protocols

The problem is not finding compliant devices, the problem is making your devices compliant. It might be better to give a detailed description of what you are trying to achieve, then perhaps someone can suggest the best venue to pursue. In general all communication protocols have a host//master and a client/slave. In some protocols the roles can be interchanged, in others they cannot. I will warn you that "the simpler a device is to use, the more complicated it is to design/build/maintain", almost 100% of the time. Wireless protocols are absolutely not an exception to this general statement.

Fish

 

[Lelan]

Thanks for the answer. I'll try to explain you a little bit more :

We have a population of 20 monkeys (black and grey).
Some of them like to eat bananas, others prefer apples, and others nuts.
We put a device on each monkey, entering previously its gender and its preference, and put all of them into the park.
We would like that :
- when a black and a grey monkey witch both like bananas get closer (a from 10m to touch each other), the Led on both of their devices switch ON, and stay ON while they stay inside of this area
- when 2 black monkeys which both like bananas get closer, it can also switch ON
- when it is 2 black monkeys, but one like nuts and the other apples, then the devices check that they do not like the same food, and so both of the Leds stay OFF.

This an example, but the idea is to configure each device with some points to be checked, and when 2 devices enter in the area of a possible connection, then they make an automatic connection to check if the information they have is "compatible" and let it know via its Led.

Is it clearer ?
(I am aware this is complicated, but the challenge is always good !)

 

[Fish4Fun]

I guess the most important question is what is this project's budget? And the second most important question is how precisely do you want to track the monkeys?

You mentioned the distance was < 10m, suggesting an area of < 100m^2. You might consider a surveillance camera and a PC with some software to distinguish one monkey from another. The software might be a little tricky, but the system aside from that should be fairly cheap.

Fish

 

[Lelan]

Well, the idea would be not to spend a lot of money, but I am quite sure that this kind of project needs a strong basis which costs. Then here, I also wanted to make me an idea of the budget I would need once I know which technology should be used.

I didn't wanted to put a camera to track the monkey (well, maybe it is necessary at the end, it is quite difficult for me to know that), but I wanted to enter some parameters related to each monkey myself in each device (registering that it is black, and tall for example, in one hand, and in the other hand registering that it loves bananas), and make it for each monkey.
Then, when two monkeys are sufficiently close one to the other (10m maximum), the devices would be able to detect that there is another device near itself, and make a connection to check if the info the other get is compatible or not. I would prefer not to reduce the space where they are, and imagine a device which can work properly in every type of space (just detecting when there is another device near it).

The program I would need to produce will not be a real problem for me, but the material I need to use is another thing.
I would prefer not to have to use a camera, in any case.
Would that be possible without ?