Easy task without rosserial :-)

because of a lot of pain with rosserial, I prefer an alternate solution for ROS and ARDUINO.

Arduino + Firmata

PyMata (Python2) or PyMata-AIO(Python3)

you can do it with the following componenets:

Arduinos flashed with Firmata

Raspis with simple python pymata node ( https://github.com/MrYsLab/PyMata )

• one RPI node reads ADC and publish it to topic.

• one RPI node subscribe to topic and writes data to Arduino

export ROS_MASTER_URI=http://notebook:11311

Done.

Advantage of this solution:

you need to program simple nodes with pymata only.

Example

Connect Potentiometer to ARDUINO 1 or 2 at Pin A1

Connect Servomotor to ARDUINO 1 or 2 Pin D9

Edit sample code for correct USB port

export your ROS_MASTER_URI=http://roscore_ip:11311

Code

https://github.com/mockbot/MockBot/bl...

Enjoy it.

Chrimo

This is definitely achievable using the rosserial package as described here along with the tutorials here.

Using rosserial a pseudo node runs on the arduino and is able to publish and receive messages itself, however it needs a regular ROS node running on the device it is directly connected to using a serial (or serial over USB) the rosserial_python node is generally used for this.

Since ROS is a distributed network system it does not matter which device on the network is running roscore as long as every device can connect to it.

In your use case you could run the roscore on either of the Raspberry PIs or the laptop. Each of the PIs would need to run the rosserial_python node to connect to their respective Arduinos. You would then write a rosserial publisher node as described here on one Arduino and a subscriber node on the other.

Hope this gives you a good idea how to do this.