MKI's profile - activity

Hi,

I am currently working with a 2d laser scanner (PLS101-312). There are no registered drivers available for this device in the ROS repositories. however, following this answer, I was able to find a fork on git here, which works pretty fine on the device I am working on. I could also see the stream of laser data using $ rostopic echo /scan

My question here is, How can I view the laser scan data on rviz? When tried the /scan topic on rviz, I get an error saying that the frame for laser_scanner cannot be /world, the example here shows that it is being set to a base_laser. how can I do the same? I am aware that, there should be a tf for my laser_scanner, what would be the simplest way of setting up a tf for the laser, just for testing the laser scanner output? please suggest, some Ideas.

Thanks again,

Murali

I was not able to find a solution with qt and C++; so I switched over to GLADE+gtk+python for GUI development, it is relatively simpler to understand and quicker to code. There are some issues with this method too ( ~ similar to the one mentioned above); will post the link shortly.

Hi ROS Users,

The ROS community has grown tremendously over the last 2 years, and it is good to be part of this growing community. Previously I tried to install ROS (Groovy) on Raspberry Pi using this tutorial and it was successful (Debian installation). I also understand that there is Hydro Installation (installation from Source) which requires lot of time for compilation. So now My questions are,

1. how should one proceed to install the latest version of ROS (For eg. Indigo ) on Raspberry Pi from source?
2. how to create a ROS Indigo debian release, after installing from source (I would like to try this)?

it is also much appreciated if someone can give pointers to a debian installation of Hydro on Raspberry pi. Thanks again, and thanks to the whole community,

Best Regards,

Murali

Hi,

earlier during the times of fuerte, groovy and I guess to some extent in hydro versions there was the concept of dry packages (which follow rosbuild) and wet packages (which follow the catkin build structure). Please correct me if I am wrong, In newer versions (indigo, jade and future releases...) the concept of dry package no more exists and will not exist. So I have few questions on this regard:

1. Suppose one has to use a package having rosbuild structure in a newer version of ROS, would it be possible to rebuild the source code simply by using catkin_make on my ~/catkin_ws/src folder containing my dry package?
2. What are the challenges involved in moving the rosbuild package from a lower version of ROS to a latest version?
3. What are the challenges involved in moving the catkin package from a lower version of ROS to a latest version?
4. Issues with respect to dependency, Will this be the main problem one has to handle, when working with same package on different versions of ROS? or are there many more issues one has to take care of?
5. I have gone through the concept of overlay, will it be useful for the above tasks?

these are lot of questions, under one heading. But, I somehow feel these tasks will be a little tricky when handling several packages of different build structure for many ROS users. Awaiting response from experienced users.

Thanks and Regards,

Murali

EDIT: for example let us consider these packages here and this one here.

Hi,

I am working on qt based GUI tool that I found in ROS wiki. As I understand, this package provides the basic requirement to interface Qt to ROS by means of a QNode class (a Thread). This package template, publishes chatter topic by means of the QNode Thread, using the run method. so my question is, how can one publish/subscribe values from Qt elements like a qSlider, qButton, qLineEdit, qProgressBar... etc to ROS? I am not very familiar with Thread programming, How can I pass these values to the QNode Thread...? PFB is portion of code to get an Idea:

    /*********************
    ** Logging
    **********************/
    ui.view_logging->setModel(qnode.loggingModel());
    QObject::connect(&qnode, SIGNAL(loggingUpdated()), this, SLOT(updateLoggingView()));

/*********************
** Auto Start
**********************/
if ( ui.checkbox_remember_settings->isChecked() ) {
    on_button_connect_clicked(true);
}

/*********************
**

Values That I need to publish

**********************/
ui.linearVelprogressBar->setValue(ui.linearVelhorizontalSlider->value());
ui.angularVelprogressBar->setValue(ui.angularVeldial->value());

connect(ui.linearVelhorizontalSlider,SIGNAL(valueChanged(int)),ui.linearVelprogressBar,SLOT(setValue(int)));
connect(ui.angularVeldial,SIGNAL(valueChanged(int)),ui.angularVelprogressBar,SLOT(setValue(int)));

here is sample GUI...

If anyone has worked on this, Please give me an Idea to perform the above... Thanks in advance.

Murali

Hi All,

I would like to install two versions of ROS --> Groovy and Hydro (or Groovy and Fuerte for example). Is it fine to work this way or should I have only one version of ROS installed? Has anyone tried this before?

Thanks Murali

your raspicam node will not work if you don't have userland installed in your pi as there is a direct dependency to this. If using Indigo, you should have installed from source all the packages mentioned. but with groovy you can simply apt-get your packages. you can very well try it with Indigo!

well, I don't know why you have to cross compile this code? you can just copy/download it into you Pi, and cd userland and ./buildme in your pi's terminal. it takes around 45 mins to build. and then following the README.md you should be able to rosrun it, Also please mind its on groovy nt Indigo

probably you are right, I am able to run the node on groovy (@90 fps too). have you built the userland source code? I ask because, the README.md file does not mention anything on building this code. I guess that you might have missed this step and you are not able to find the right binaries.

I just saw the link you have mentioned, It seems this package was built with Groovy in consideration (check README.md file) . I could manage only bare bones version of Indigo. However, I'll give this package a try n let u know

may I ask which version of ROS you are using?

On your PC, You should have done the following:

export ROS_MASTER_URI=http://<your-pc-IP>:11311

export ROS_IP=<your-pc-IP>

and then when you use your android device, try connecting with

connect: http://<your-pc-IP>:11311

It should work! hope this helps.

mk

Hi,

Right now, Like you have mentioned the usb_cam has source code for wet build (catkin build). you just need to do the following to build it from source. (Note: I assume you are using ROS hydro or Indigo, It should work on groovy as well may be you can try it). But all that said, here you go:

$ mkdir -p ~/catkin-ws/src

$ cd ~/catkin-ws/src

$ git clone https://github.com/bosch-ros-pkg/usb_cam.git

$ cd ..

$ catkin_make

$ source ~/catkin-ws/devel/setup.bash

after the above you can verify using ..

$ roscd usb_cam

roscore on a new terminal $ roscore

and then in the terminal where you $ source 'd your usb_cam code run:

$ rosrun usb_cam usb_cam_node

Make sure you have your camera connected, before running the above command!!! you view the captured image on rviz,

$ rosrun rviz rviz

hope this helps. mk

Not sure if it is still relevant to you! but did you check your uc baud rate?