Connect two odrive boards

[MoonWalkerAZ]

How can I connect two odrive boards, so that I would be able to control four motors ?

I tried this:

odrv0 = odrive.find_any(serial_number="my_serial")
self.driver = ODriveInterfaceAPI(active_odrive=odrv0, logger=ROSLogger())

But the problem is if one onedrive gets disconected. Then it is unable to reconnect.

[MoonWalkerAZ]

If you want to connect odrive by its serial number do the following:
In file odrive_interface.py change connect function:
from

def connect(self, port=None, right_axis=0, timeout=30):
...
self.driver = odrive.find_any(timeout=timeout, logger=self.logger)

to

def connect(self, port=None, right_axis=0, timeout=30, serial_number=None): 
...
self.driver = odrive.find_any(timeout=timeout, serial_number=serial_number, logger=self.logger)

And in file: odrive_node.py change:
from
if not self.driver.connect(right_axis=self.axis_for_right):
to
if not self.driver.connect(serial_number= "my_serial",right_axis=self.axis_for_right):

If you want to run both boards at the same time you should run two separate nodes ?

[MoonWalkerAZ]

I tried running two odrive nodes at the same time, but when I send zero velocities to both odrive boards:
rostopic pub /cmd_vel geometry_msgs/Twist '{linear: {x: 0.0, y: 0.0, z: 0.0}, angular: {x: 0.0,y: 0.0,z: 0.0}}' -r 10

I get this error:

[ERROR] [1641035058.119541]: ODrive USB connection failure in fast_timer.Traceback (most recent call last):
  File "/home/pi/catkin_ws/src/odrive_ros/src/odrive_ros/odrive_node.py", line 304, in fast_timer
    error_string = self.driver.get_errors()
fibre.protocol.ChannelBrokenException

[ERROR] [1641035058.132330]: Error in timer: Traceback (most recent call last):
  File "/home/pi/catkin_ws/src/odrive_ros/src/odrive_ros/odrive_interface.py", line 102, in disconnect
    self.release()
  File "/home/pi/catkin_ws/src/odrive_ros/src/odrive_ros/odrive_interface.py", line 255, in release
    axis.requested_state = AXIS_STATE_IDLE
  File "/usr/local/lib/python3.8/dist-packages/fibre/remote_object.py", line 258, in __setattr__
    raise AttributeError("Attribute {} not found".format(name))
AttributeError: Attribute requested_state not found

Result is that one odrive board disconnects itself.
When I send any other velocities that move the wheels I don't get this error. The problem only shows it self when I try to keep motors at fixed position. Also if I only launch one odrive board and send velocities 0 I don't get an error. I don't know why.

Can someone help ? @neomanic