Is there simulation oriented tutorials?

edit

hello.

There is a section in the tutorial version 1.3, that is not on 1.4 and 1.5, "Controling a robot". specialy (http://gazebosim.org/wiki/Tutorials/1.3/intermediate/controlmodel) and (http://gazebosim.org/wiki/Tutorials/1.3/controlrobot/mobile_base) , this should get you a good idea how to move robots with the model velocity or with joint commands.

i advise you to first get a simple plugin controlling the robot movement avoiding obstacles and then, if you want to control it with ROS, make a ROS-enabled plugin like the one in the tutorials and edit it to subscribe linear and angular velocity from a ROStopic with geometrymsgs/Twist (http://ros.org/doc/api/geometrymsgs/html/msg/Twist.html).

You should research about message types for rostopics, publishing and subscribing to ROStopics with diferent message types before trying to create your own plugin to talk with ROS

SIDE NOTE: once you have some insight of the tutorials this might be usefull to save you sometime later on if you are not familiar with quaternions (i wasn't), so remember this when you try to get a robot Roll Pitch Yaw angles:

math::Quaternion r = model->GetWorldPose().rot;
//from quaternion to roll pitch yaw, in radians
qw=r.w;     qx=r.x;     qy=r.y;     qz=r.z;
Rrad=atan2(  2*(qw*qx+qy*qz),  1-2*(qx*qx+qy*qy)  ); //roll
Prad=asin(2*(qw*qy-qz*qx));                          //pitch
Yrad=atan2(  2*(qw*qz+qx*qy),  1-2*(qy*qy+qz*qz)  ); //yaw

this might also be usefull in the model plugin (not joint velocity commands tho):

//set velocities
float Vlin=0.5; //Linear velocity wanted
float Vang=1.0; //Angular velocity wanted
float velx=Vlin*cos(Yrad);
float vely=Vlin*sin(Yrad);  
this->model->SetLinearVel(math::Vector3(velx, vely, 0));
this->model->SetAngularVel(math::Vector3(0, 0, Vang));

the above code will make the robot move in a circle. you can then, with laser data for example, change Vlin and Vang to your will.

i hope the above code examples will save you time instead of spending to much time trying to learn everything by yourself like i did.

EDIT added a somewhat simple/basic plugin i'm using to publish to rostopics, might be usefull http://answers.gazebosim.org/question/1991/what-is-the-best-way-to0-learn-gazebo-in-ros-for/