Azhar's profile - activity

this is my package: https://github.com/azhar92/GUI-for-AV...

When I open rqt and try to open the plugin from the drop-down menu using the following steps

cd ~/catkin_ws
catkin_make
source ~/catkin_ws/devel/setup.bash
rqt --force-discover

I can see the name of my package when in the rqt gui, but when i click it,

I get the following error in the terminal output:

[ERROR] [1482121854.496133919]: Failed to load nodelet [rqt_test1/MyPlugin_1] of type [rqt_test1/MyPlugin]: MultiLibraryClassLoader: Could not create object of class type rqt_test1::MyPlugin as no factory exists for it. Make sure that the library exists and was explicitly loaded through MultiLibraryClassLoader::loadLibrary()
RosPluginlibPluginProvider::load_explicit_type(rqt_test1/MyPlugin) failed creating instance
PluginManager._load_plugin() could not load plugin "rqt_test1/MyPlugin": RosPluginlibPluginProvider.load() could not load plugin "rqt_test1/MyPlugin"

i think it has to do with the registration of the plugin. any form of guidance will be helpful. Thank you.

Plugin.xml : https://github.com/azhar92/GUI-for-AV...

Code:

<library path="lib/librqt_test1">

 <class name="rqt_test1/MyPlugin" type="rqt_test1::MyPlugin" base_class_type="rqt_gui_cpp::Plugin">

   <description>

4 buttons to switch between 4 different modes.

</description>

 <qtgui>

  <group>

   <label>Visualization</label>

    <statustip>Plugins related to visualization.</statustip>

  </group>

 <label>test1</label>

 <statustip>4 buttons to switch between 4 different modes.</statustip>

 </qtgui>

</class>

</library>

i have been trying to read all the forums and tutorials , but i dont know where to start. Please guide this noob.

so there are two parts to my question.

i want to make a custom rqt plugin using Qt 5.7. I have already created the user interface in Qt 5.7. so how can i integrate it into ROS(so that it appears as one of the rqt plugins)

a) i have went through the tutorial of how to create a cpp rqt plugin . I dont know what to do after i create all the files(Cmakelist.txt, package.xml, plugin.xml, my_plugin.cpp, my_plugin.h). What to do after that? how can i ensure i can see the rqt plugin in the rqt plugin list. Am i missing anything?

b) this user interface is actually for a moving vehicle(teleoperation). How to use callback/Signal and Slot function to ensure i can communicate(send commands ) via the user interface?

#in Qt, when i click New project -> Import project,i cant see Import ROS project. i tried to run Qt thru terminal but to no avail.

Anyone who could at least guide about how to do would be very beneficial to me. Thank you.

Currently, the mobile robot works by navigating from station to station, autonomously.

I want to make the mobile robot travel to any point i point it to (the 2D Navigation goal in RVIZ).

May i know what changes i should do to make this work?

I am new to Navigation , so any guidance would be appreciated!

I have looked through the tutorials, but i dont know where to start http://wiki.ros.org/navigation/Tutori...

http://wiki.ros.org/turtlebot_navigat...

Hope this helps.

it froze again when i open image_view in rqt too. However, when i open both the map and image(theora) from Rviz it works fine. :)

Do take note that i am using to view all this from a slave machine.

Currently, when i try to visualize the Laserscans in RVIZ alone, it freezes. Debugging in progess!

I solved the issue by downloading the LIDAR MAP(.yaml ) in my laptop and run from there. Thanks people. I encountered a new problem which i will be opening a new question on.

TRY THIS.

 sudo apt-get install ros-indigo-bfl

ok.

A : Control station, my laptop B: mobile robot

in A,

export ROS_IP=<IP address of A>

export ROS_MASTER_URI=http://<IP address of B>:11311/

in B (MASTER),

export ROS_IP=<IP address of B>
roscore

I am working on a tele-operation mode of a mobile robot, from a control station.

The control station and the robot is connected to the same WIFI network and both can ping to each other.

The problem comes when i want to see the LIDAR map/readings on the control station.

When i rostopic list on my control station, i could see the topic. However, when I echo that topic, i didn't receive any message. When i open RViz and add the map , it doesn't show anything(because the message wasn't received in the first place). RViz freezes too when i try to add the map. This does not happens to the other topics. For eg, the topic odom can be echo-ed.

I tried with Ethernet , it works(but it has its own issues ), but i need to be connected through a same WIFI network.

What could be the problem here??

1) Too much data being published?(when i do a rostopic echo in the vehicle, my screen would be flooded with values)

2) WIFI connection? (i set up a bidirectional networking by exporting ROS_IP and ROS_MASTER_URI, do i have to do anything else?)

3) RViz issues? (it freezes, turns grey when i try )

4) Any other things i am missing out?

and possible solution for this?

Hi, I tried it, RVIZ standalone and it still freezes! :(

Can anyone give me a heads up of what to check? Network? laptop configuration?

Thank you for your response! :) Will try to do it!

I wanted to create a GUI with everything on one screen. I was just thinking what could be the reason, and how to improve it.

Any idea of how to handle high amount of data so that it will flow with low latency?

I am creating a GUI for a robot using rqt_gui, both connected together by the same WIFI network.

The plugins in my rqt_gui are 1) RVIZ, 2) Image_view and 3)dynamic_reconfigure.

Whenever i run the rqt_gui, and access RVIZ , the whole rqt_gui freezes and turns black shortly. Thus i am unable to do anything with it.

RVIZ - For LIDAR map and navigation through it

Image_view - To have live camera feed from the robot

rqt_dynamic_reconfigure - to change the parameters of the robot from the laptop

Can someone please tell me why am i facing the problem and is there any solution to the problem!

My laptop is Lenovo ideapad 700 running in Ubuntu 14.04 and ROS Indigo.

Please let me know if there is need for any other info.

Any form of help would be apprciated!

THANKS @gvdhoom!

i managed to get what i want using the dynamic_reconfigure!

General info: The config is a dictionary which stores the True/False value of the parameter. So by playing with it , you can control what you want to do!

#!/usr/bin/env python
PACKAGE = 'dynamic_tutorials'
import roslib;roslib.load_manifest(PACKAGE)
import rospy
import dynamic_reconfigure.client

from geometry_msgs.msg import Vector3, Twist

def callback(config):
    global pub,tw,cw,global_name, client
    print config
    global_name = config['bool_param']

pub = rospy.Publisher('/turtle1/cmd_vel', Twist)    
tw = Twist(Vector3(1,2,0), Vector3(0,0,1))
cw = Twist(Vector3(1,2,0),Vector3(0,0,-1))

if __name__ == "__main__":
    rospy.init_node("dynamic_client")
    rospy.wait_for_service("/dynamic_tutorials/set_parameters")

    client = dynamic_reconfigure.client.Client("dynamic_tutorials", timeout=30, config_callback=callback)

   r = rospy.Rate(1)
   global_name = rospy.get_param("/dynamic_tutorials/bool_param")
   while not rospy.is_shutdown():              
   if global_name:
        pub.publish(tw)
    else:
        pub.publish(cw)

    r.sleep()

i need dynamic_reconfigure to able to change between modes for an autonomous vehicle, which is the ultimate goal. I am using turtlesim to find out how it can be done first.

Is it possible for you to guide me what i should have in my callback, to get the intended function? Any form of guide! :)

Basically I want an on/off button in my dynamic_reconfigure, to publish my customized data. So if the button is "on", it would publish the data.

Current problem : 1) the button in the dynamic configure does not have any effect on the turtle when turned "on" or "off".

this is my client.py

#!/usr/bin/env python

PACKAGE = 'dynamic_tutorials'
import roslib;roslib.load_manifest(PACKAGE)
import rospy
import dynamic_reconfigure.client

from geometry_msgs.msg import Vector3, Twist

def callback(config):
    rospy.loginfo("Config set to {bool_param}".format(**config))

if __name__ == "__main__":
    rospy.init_node("dynamic_client")
    pub = rospy.Publisher('/turtle1/cmd_vel', Twist)
    rospy.wait_for_service("/dynamic_tutorials/set_parameters")
    tw = Twist(Vector3(1,2,0), Vector3(0,0,1))
    client = dynamic_reconfigure.client.Client("dynamic_tutorials", timeout=30, config_callback=callback)

    r = rospy.Rate(1)
    x = 0
    b = True

    while not rospy.is_shutdown():

        x = x+1
        if x >5:  
            pub.publish(tw) 
            x=0   

        client.update_configuration({"bool_param":b})
        r.sleep()

When i run my server.py and client.py and turtlesim_node and dynamic_reconfigure, the turtle in the turtlesim node goes in circle every 5 seconds(regardless if the bool_param in dynamic reconfigure is ticked or unticked). If i click the bool_param, it becomes unticked immediately.

Intended action: When i click on a button(bool_param, in this case is ticked) in rqt_dynamic_reconfigure , it should publish the command and remain publishing the command untill i give further instructions.

How can i implement this action? I need to control the turtle movement using dynamic_reconfigure.

Thank you!