publishing OSC messages via ROS

Question

I need to write a ROS publisher node (and then subscriber node) using IMU data which is published from the IMU using OSC. I have a python script which will print the data to screen but I need to be able to publish this via ROS.

I have seen rososc but this seems linked to using smart devices which I'm not using and I just don't know enough to be able to convert it to what i need.

I've written some code using examples I've found as a basis but at the moment it just publishes 'none' instead of the data stream.

How do i get the OSC published in a ROS node and not just to screen?

Here is my code - it's basically the same as the original script but with some ROS commands mixed in.

# I've added this function
def handlerfunction(s, x, y, z, w): 
    # Will receive message data unpacked in s, x, y
    pass

def generate_imu():
    parser = argparse.ArgumentParser()
    parser.add_argument("--ip", default="0.0.0.0", help="The ip to listen on")
    parser.add_argument("--port",
      type=int, default=8084, help="The port to listen on")
    args = parser.parse_args()

    dispatcherObj = dispatcher.Dispatcher()
    # dispatcherObj.map("/quaternion", print) #- original command to print data to screen
    pub=rospy.Publisher('imu_pub',Float32,queue_size=10)
    rospy.init_node('generate_imu')
    while not rospy.is_shutdown():
        #/quaternion is imu data followed by numerical data. I replaced 'print' with handlerfunction
        ngimu_out = dispatcherObj.map("/quaternion",handlerfunction)
        rospy.loginfo("imu: %s", ngimu_out)
        pub.publish(ngimu_out)

    server = osc_server.ThreadingOSCUDPServer((args.ip, args.port), dispatcherObj)
    print("Serving on {}".format(server.server_address))

    server.serve_forever()

The commented line is I get: [INFO] [1556016429.254443]: imu: None

I want to get: [INFO] [1556016429.254443]: imu: 0.02763 3.282368 9.367127 0.32357235 0.775263

If anyone can help or even point me in the right direction I'd be so thankful.

tia

Answer 1

# I've added this function
def handlerfunction(s, x, y, z, w): 
    # Will receive message data unpacked in s, x, y
    pass

This part doesn't do anything.

How about trying this?

class imu_data:

    def __init__(self):
        self.s = 0
        self.x = 0
        self.y = 0
        self.z = 0
        self.w = 0


# I've added this function
def handlerfunction(s, x, y, z, w): 
    # Will receive message data unpacked in s, x, y
    newData = imu_data() //creating new object
    newData.s = s;
    newData.x = x;
    newData.y = y;
    newData.z = z;
    newData.w = w;
    return newData

And:

rospy.init_node('generate_imu')
ngimu_out = new imu_data()
while not rospy.is_shutdown():

Could you check if it works please? If it doesn't try to print it separately.

print("s: " + ngimu_out.s)

Like this for example