pgarcia's profile - activity

global_planner eventually creates paths over obstacles when calling /GlobalPlanner/make_plan Hi all! I'm using Gmapping

apparently, it does ;)

Thank you very much for the answer. As you suggest, replacing base_link by camera_pose_frame makes it work. Additional

Great, thanks!

hector_slam/gmapping with T265 (odometry) and RPLidar Hello everybody I am trying to make SLAM using a 2D laser scanner

hector_slam/gmapping with T265 (odometry) and RPLidar Hello everybody I am trying to make SLAM using a 2D laser scanner

bebop_autonomy on Raspberry Pi 3 (Raspian-stretch), parrot_arsdk won't compile Hello there! I'm trying to run bebop_aut

bebop_autonomy with from-source-compiled parrot_arsdk in Raspberry Pi 3 Hello there! I'm trying to run bebop_autonomy o

Hello Ahendrix

Thank you very much for your answer. The code above actually works. The problem was in another part of the code: the topic /topic_B was not actually being published continuously. That is why B_member.x was not updated.

Hi everybody!

I'm having some problems with a simple program. There is a main class A, which uses a second class B. Both of them are subscribed to different topics. I simplified both of them:

class B {
   private:
      ros::NodeHandle n;
      ros::Subscriber sub;
   public:
      float x;

      void callBack_B(const type_1 msg){
        x=msg.data
      }

      B() {
        sub=n.subscribe("/topic_B", 1, &B::callBack_B, this);
        x=0;
      }
};

class A {
   private:
      ros::NodeHandle n;
      ros::Subscriber sub;
      ros::Publisher pub;
   public:
      float y;
      type_2 z;
      B B_member;

      void main_process_A(const type_3 msg){
        y = msg.data
        z.data = B_member.x + y;
        pub.publish(z);
      }

      A() {
        sub=n.subscribe("/topic_A", 1, &A::main_process_A, this);
        y=0;
      }
};

int main(int argc, char **argv)
{

  ros::init(argc, argv, "my_node");

  A A_member;
  ros::spin();

  return 0;
}

I hope I did not make any mistakes in this code; anyway my code is similar and compiles without any problem.

The thing is that B_member.x does not update! Its value is always the same! What am I doing wrong? I know one solution would be to merge A and B in the same class, but I would like to understand how ROS works...

Thank you very much in advance!!

Ok, I fixed it!

I was executing the publisher in the Raspberry as super user (because one of the libraries I use needs it). Then, editing the .bashrc under super user, fixed the problem.

Thanks for your comment! Yes, I added them to both .bashrc.

To be sure, I also run echo $ROS_HOSTNAME, and both were right (raspberrypi1 and pablo).

Hi everybody,

I'm running ROS in two machines, in my laptop and in a Raspberry Pi. I'm connecting them through an Ethernet cable. I configured the hostnames in both of them (/etc/hosts):

Laptop:

127.0.0.1       localhost
127.0.1.1       pablo-Aspire-V5-573G
10.42.0.1       pablo
10.42.0.97     raspberrypi1

Raspberry pi:

127.0.0.1       localhost
::1             localhost ip6-localhost ip6-loopback
fe00::0         ip6-localnet
ff00::0         ip6-mcastprefix
ff02::1         ip6-allnodes
ff02::2         ip6-allrouters

10.42.0.97      raspberrypi1
10.42.0.1       pablo

With this configuration, I can ping between them without problem, i.e. ping raspberrypi1 at my laptop, and ping pablo at the Raspberry Pi. Also, I use:

At my laptop:

export ROS_HOSTNAME=pablo
export ROS_MASTER_URI=http://pablo:11311

At the Raspberry Pi:

export ROS_HOSTNAME=raspberrypi1
export ROS_MASTER_URI=http://pablo:11311

So I want my laptop to be the master, and the Raspberry to be the slave and send messages to my laptop.

Well I ran roscore at my laptop, and I see:

pablo@pablo-Aspire-V5-573G:~$ roscore
... logging to /home/pablo/.ros/log/fc0545e6-0620-11e6-8814-78843c3472e1/roslaunch-pablo-Aspire-V5-573G-6959.log
Checking log directory for disk usage. This may take awhile.
Press Ctrl-C to interrupt
Done checking log file disk usage. Usage is <1GB.

started roslaunch server http://pablo-Aspire-V5-573G:54165/
ros_comm version 1.11.16


SUMMARY
========

PARAMETERS
 * /rosdistro: jade
 * /rosversion: 1.11.16

NODES

auto-starting new master
process[master]: started with pid [6971]
ROS_MASTER_URI=http://pablo-Aspire-V5-573G:11311/

setting /run_id to fc0545e6-0620-11e6-8814-78843c3472e1
process[rosout-1]: started with pid [6984]
started core service [/rosout]

It's taking ROS_MASTER_URI=http://pablo-Aspire-V5-573G:11311/ , but not ROS_MASTER_URI=http://pablo:11311/ as I was expecting! Actually pablo-Aspire-V5-573G is the hostname of my computer in Ubuntu, and ROS takes this one, instead of the one a gave him (pablo). When I run a publisher at the Raspberry Pi, I get:

Unable to register with master node [http://localhost:11311]: master may not be running yet. Will keep trying.

I could fix it just changing everywhere pablo by pablo-Aspire-V5-573G, but still I wonder why it is not working.

Any ideas?