shpower's profile - activity

integrate systemplugin with gazebo Hello, I want to integrate a systemPlugin such as this: http://gazebosim.org/tutoria

In addition to tutorials there are two good books: 'ROS BY EXAMPLE' vol.2 (vol.1 is good for turtlebot, but without gazebo) and 'Mastering ROS for Robotics Programming'

I read it from physics gztopic. What do you mean?

Hey All,

I run into old xml file of box description. under inertia properties ixx,iyy and izz I saw another fields cx,cy,cz which I haven't met till now. Does sombody knows what this fields represent?

Thanks in advance

Hey all,

I created a cylinder (Wheel) on a ground plane. when the wheel was at rest the contact force was the weight of the wheel (~25.0 N). after I applied a constant angular velocity(linear is 0) by SetAngularVel(), the contact force on the wheel changed to be sinusoidal (from -25.0 to 25.0). Can somebody explain that?

Thanks in advance

If you don't have a publisher in the topic, you must create one in the plugin code (not the sdf file).

If you don't have a publisher in the topic, you must create one in the plugin code (not the sdf file). This is an example of the code you should add in the plugin: if (!ros::isInitialized()) { int argc = 0; char** argv = NULL; ros::init(argc, argv, "brixiusplugin", ros::initoptions::AnonymousName); }

        brixius_result_pub_  = nh_.advertise<brixius_gazebo::brixius_result>("/brixius_result", 1000);

Hey,

I am trying to simulate a wheel(cylinder) on a surface (ground_plane). I launch the gazebo with sdf file which contains both models and give it a 3 seconds to get rest with parameters Kp =380 and Kd=10. I can see the spring rest when I look at the output of position and velocities commands of z axis (GetWorldCoGPose() and GetWorldCoGLinearVel() gazebo API commands), but when I use GetWorldLinearAccel() command I get acceleration z value as zero although the wheel is moving. Sombody knows why? maybe the GetWorldLinearAccel() is not the right command?

Thanks in advance

I see you managed to solve this problem. anyway the small Kd such as Kd=1 worked for me.

start from larger values for Kp like 10^7 (you can try even larger) and go lower till you will see a penetration. after that you can add a compatible Kd.

which Kp and Kd values do you use? t

Hi,

I saw this command:

boost::sharedptr<msgs::response> response = transport::request(getworld(), "world_sdf");

Can somebody explain how the request command works? Is there a list of requests that I can send?

Thanks in advance,

and of course thanks a lot!

I have a question about the code. the "world_sdf" is the name of the request, correct? Is there a list of requests

I have a question about the code. the "world_sdf" is the name of the request, correct? Is there a list of requests

Hey,

I want to be able to save the world several times during the simulation, programmatically in c++ gazebo plugin. I mean to get the same file as if I press "save world as" in the gazebo gui.

thanks in advance,

Hey

I created a world file that includes three blocks. I want to know the contact normals between them so I subscribed to ~/physics/contacts topic. On the start when I start the gazebo and echo the topic the topic doesn't show any contacts (publish empty messages) although I can see the blocks. the topic start publishing contact normals after I move the blocks or add another one.

Does somebody know why is that happening and how I can fix that?

Thanks in advance

Hey,

gazebo wiki has a link problem. Almost all links are broken. Whats going on here?

Thanks in advance.