Ah ok, I understand.  For efficiency, rather than computing the distance to
each point in the cloud each time, you can project the cloud into a grid
representing the robot configuration space and inflate each obstacle.  This
is already implemented in the costmap_2d ROS package.
- Bhaskara

2011/1/18 Nicolás Alvarez Picco <nicolasapicco@hotmail.com>

>  Hi Everybody!!
>
> I want to detect objects, but just their position to avoid them with the
> laser data. So I am using these lines:
>
>    for(int it=0; it<size_cloud; it++){
>
> dist_obstacles=sqrt(pow(pts_laser->points[it].x-state2.pose.x,2)+pow(pts_laser->points[it].y-state2.pose.y,2));
> //distancia entre 2 muestras consecutivas
>
>         if(dist_obstacles <= robot_r)  {// quiero decir si el centro de mi
> robot esta a mas de la distancia del r significa q esta en un estado a
> seguro!!! y 4 metros es el mx alcance de mi laser
>
>             return false;
>         }
>   }
>
> where pts_laser is a pcl_pointcloud and the state2 give me the future
> position of the robot.
> So it is a checker, if there is a point which is closer to the robot than
> the radius of the robot, so that state is unsafe.
> This thing is not working well. So do you have a better solution or an
> idea??
>
> Thanks
>
> Nicolas
>
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>


-- 
Bhaskara Marthi
Research Scientist
Willow Garage Inc.
650-475-2856