Arduino to Arduino bluetooth communication

Projects General Guidance
1

Hi all!

I need your help please for the following project:

I want to transfer some functions from a radio control transmitter to outside. The goal is to have one person controlling a multirotor and other controlling the camera functions like camera angle, zoom, trigger etc.

The idea was to put a Bluetooth with an Arduino pro inside of the transmitter controlling some hardware like digital potentiometer, and some analogues switches and simulate the transmitter functions like switches and potentiometers. Outside another Arduino reading some potentiometers and switches send the information through Bluetooth to the transmitter. A good distance should be between 10 and 20 meters.

My problem is that I do not know nothing about Bluetooth, pairing, etc. I think that we need a transmition with paring because the radio control transmitter has a 100mw power and there are also some other transmitters around that can interfere with the Bluetooth communication.

The options I thought are:

Option 1: http://www.ebay.com/itm/1pcs-TTL-Bluetooth-Module-with-adapter-board-for-arduino-free-connecting-cable-/321030648793?pt=US_USB_Bluetooth_Adapters_Dongles&hash=item4abeeaf3d9

Option 2: Bluetooth Mate Silver - WRL-10393 - SparkFun Electronics

Option 3: Bluetooth Modem - BlueSMiRF Silver - WRL-10269 - SparkFun Electronics

Option 4: http://www.cooking-hacks.com/index.php/shop/wireless/315mhz-rf-link-kits-with-encoder-and-decoder.html

Option 5: http://www.cooking-hacks.com/index.php/shop/wireless/rfm22b-s2-smd-wireless-transceiver.html

Option 6: http://www.elechouse.com/elechouse/index.php?main_page=product_info&cPath=&products_id=324

First option: The advantage is that it comes already soldered on a pcb with power supply and TTL level adjusted, and cost. Disadvantages, I do not know how to put it working one as master and the other slave and make the pairing.

Second option: it looks like the setup is easier and there is already a sketch example. Disadvantages, to buy 2 is a bit expensive. I do not know how to pairing.

Third option: it looks like it is more difficult to set up than the 2th option, and it is also a bit expensive.

Fourth option: advantages, it is low cost, Freq. 433MHz longer transmit distance. Disadvantages, I do not know if it is possible to do paring.

Fifth: same as above.

Sixth: Advantage, there is more information on hoe to setup it, it is possible to make paring. Disadvantages The Bluetooth module it is not installed on the PCB with voltage regulator and TTL level converter, and it is a bit more expensive.

The above were the option I thought about, for sure there are more, your advise is welcome and as well as future help in parameterization and paring.

Thanks in advance,
Manuel

2

Hi,

In my experience (granted, using Bluetooth Bees rather than any of the modules you've quoted) a range of 10m is fine, in line of sight. When there are obstacles in the path this soon degrades, and they're prone to interference as you've mentioned. I have a class one bluetooth dongle (the Pirani UD-100) which does a great job of extending the range, and I can routinely get 20m range from a indoors PC to a bee outside with that, though I run it on a USB extension cable so it can be elevated well above the PC for best results.

For point-to-point comms like you're chasing I can't say I'd 100% trust bluetooth devices with inbuilt antennas past your lower limit of 10m but your mileage may vary.

I've been meaning to try some range testing on the Nordic alternatives - have some nRF901's, but also keen to see what the nRF905 with the antenna can do for range. They're certainly in a similar price bracket.

Cheers ! Geoff

3

Does it have to be Bluetooth? If not then look at the low power nRF24L01. They will do 20m fairly easily and can be bought for about £1.32 each on eBay from China.

I use them for a project and they work well. They connect over SPI so you need power plus 5 more connections.

Use wih the MIRF library for simple stuff, or the excellent NRF24 and NRF24Network libraries from Maniacbug.