4x4 configuration

[SerdarAbali]

Hi all,

did we have a proper 4x4 configuration? I have been asked a lot about this and the easiest solution was making two hoverboard packages with separate names and make a one common launch file to launch both packages. I connected rx/tx in parallel and it was a super easy task.

If we don't have a proper 4x4 should I make a ready solution/tutorial if my method above is ok?

Regards,

Serdar

[alex-makarov]

Serdar,

That would be great! We only have a very primitive 'full sync' 4x4 launch file, so a proper solution/tutorial is very welcome!

[quangvu16]

Hello @SerdarAbali
As I understand, the TX will send commands to boards, and RX will receive the information from boards.
If you connect TX/RX in parallel, how can computer know signal from which board to make Odom?
Thank you,

Hello @alex-makarov
I can send commands from computer to 2 boards with /cmd_vel. How do computer make Odom when it receives 2 signals of velocity and position of 2 boards?

• /front/hoverboard/left_wheel/velocity

• /front/hoverboard/right_wheel/velocity

• /rear/hoverboard/left_wheel/velocity

• /rear/hoverboard/right_wheel/velocity

Thank you,

[SerdarAbali]

This is why I don't only rx/tx connect both, but also make separate package to topic names for the odometry. But using same same .launch and hoverboard package you can only publish odometry information only for one hoverboard. I'm just waiting for my holiday (part 2) to start, I will re-assemble my 4x4 and make wiring diagram etc and packages dedicated for front and rear.

[Mo-Tro]

Sedar,
It will be great if you can do that. Looking forward to your tutorial.

[Dober2786]

That would be cool.
I recently had some issues with something similar with a joint state controller that i wanted to publish in two different topics, so the arduino doesnt have to buffer the whole message. But somehow didnt got it working properly.
So maybe i can find my mistakes by looking at your packages.

[Dober2786]

I recreated the 4x4 configuration we had at ros1. In that process I had to make it possible to change the port from the launch file. But I don't know how to contribute to a project on GitHub. Can someone help me how to do that, so I can give you my code?