How can I four SWDs with one PC?

[suguruhamada1003910]

I read the following link but I cannot resolve my issue.

Control two starter kits from one PC

When I control 4 SWDs with one PC, I think there are two method.

1. Controlling two swd_ros_controllers nodes in two PC from one PC

2. Controlling two swd_ros_controllers nodes in one PC

I think I can create method 1. Can I create method 2?

I am thinking I can create method 2 by creating two ezw-swd-left.service and two ezw-swd-right.service in one PC.

[ez-Support]

Warning CAN-IDs 0x6 and 0x7 are used by the swd services instances (in the IPC). Thus I recommand using IDs 0x14 and 0x15 for the 2 additional wheels ;) As a reminder, CAN-IDs must be unique on the CANopen bus field.

[ez-Support]

What is the set-up of your wheels on the robot ?

[suguruhamada1003910]

Warning CAN-IDs 0x6 and 0x7 are used by the swd services instances (in the IPC). Thus I recommand using IDs 0x14 and 0x15 for the 2 additional wheels ;) As a reminder, CAN-IDs must be unique on the CANopen bus field. Thank you for advice!!

What is the set-up of your wheels on the robot ? I am not sure the meaning of your question but I try to explain the details. My robot needs to carry very heavy object. The power of SWD is not enough. Therefore, I am thinking I equip four wheels in my robot.

[ez-Support]

Ok! What is the load to move and the maximum speed required ?

[suguruhamada1003910]

Ok! What is the load to move and the maximum speed required ?

I am checking information. By the way, what do you think method 2? Do you have another the best way?

[suguruhamada1003910]

Ok! What is the load to move and the maximum speed required ?

Please check below.

maximum speed：1m/s
for one starter kit, load will be around 120kg
for one starter kit, load will be around 240kg
vertical load: max. 30kg per axis

[ez-Support]

So the total load will be < 500kg? I really do think using 2xSWD-125 or 2xSWD-150 would be much easier to implement in that case. Why using a 4x wheel drive set-up here ?

[ez-Support]

Yes method2 looks better.

[suguruhamada1003910]

I correct information of AMR.

maximum speed：1m/s
for one starter kit, load will be around 120kg
for two starter kit, load will be around 240kg
vertical load: max. 30kg per axis
Size of Wheel: 200mm

User want to keep 1m/s when loading 360kg.

I really do think using 2xSWD-125 or 2xSWD-150 would be much easier to implement in that case. Why using a 4x wheel drive set-up here ?

SWD125 is not selling in Japan for now.

[suguruhamada1003910]

I don't have any query for now. I close this.

[suguruhamada1003910]

Hi Support, I am creating the following configuration.

Then, I can communicate with four SWDs by using remote.py. However, I could not control four SWDs. Specifically, only 2 SWDs are running by joy.

I am thinking dbus session is not specified correctly. In the following code, only one DBUS_SESSION_BUS_ADDRESS can be specified. https://github.com/ezWheelSAS/swd_ros2_controllers/blob/main/launch/swd_diff_drive_controller.launch.py#L17-L25

If I write code as below, DBUS_SESSION_BUS_ADDRESS is overwritten and PC can communicate with only one session.

    # Load specific dbus user session if exists
    session = "/tmp/SYSTEMCTL_dbus.id"
    if os.path.isfile(session):
        print("SYSTEMCTL_dbus.id detected")

        with open(session) as f:
            lines = f.readlines()
        env = dict(line.strip().split("=", 1) for line in lines)
        os.environ.update(env)

    # Load specific dbus user session if exists
    session = "/tmp/SYSTEMCTL_dbus2.id"
    if os.path.isfile(session):
        print("SYSTEMCTL_dbus2.id detected")

        with open(session) as f:
            lines = f.readlines()
        env = dict(line.strip().split("=", 1) for line in lines)
        os.environ.update(env)

I want to specify SYSTEMCTL_dbus.id for CAN ID 4 and5 and SYSTEMCTL_dbus2.id for CAN ID 14 and 15. Do you have any idea?

[suguruhamada1003910]

Sorry. I could specify different session ID for each SWDs by creatting another launch file.

[suguruhamada1003910]

The delay is needed to avoid overwritten DBUS_SESSION_BUS_ADDRESS.

TimerAction(
         period=5.0,
         actions=[
               swd_diff_drive_controller_description2(),
         ]),