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2014-05-07 02:55:09 -0500 commented answer navfn planning through wall

Try to use robot_radius without robot_padding and robot_footprint.

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2014-04-29 04:14:11 -0500 commented answer navfn planning through wall

Dont undestand about error. When does it appear? (When you use robot_radius parameter, ypu don't need footprint_padding at all.)

2014-04-29 04:09:58 -0500 commented answer Identify the white section of a binary image

Sorry, i'm not good in python. But OpenCV has python wrappers of every c++ function with the same names. So it will be easy for you to translate from c++ to python. Also you should take a look in python contour sample here: https://github.com/Itseez/opencv/blob/master/samples/python2/contours.py

2014-04-25 02:06:51 -0500 commented answer navfn planning through wall

Try to increase footprint_padding. (Pay attention, that you set it three times in your configs (values 0.01, 0.02 and 0.2 - i do not think that this is good idea). Or jump to robot_radius instead footprint.

2014-04-25 01:35:40 -0500 commented question gazebo+amcl+base_controller

and size of map and path length? 0.05 is pretty detailed map. I use same parameter in map size of 40x20meters and path length = ~60 meters) and have same troubles with frequency of pathfinding updates (i3 8GB). (And i do not use localization with amcl)

2014-04-25 01:10:30 -0500 commented question gazebo+amcl+base_controller

What is resolution of your map?

2014-04-25 01:07:04 -0500 answered a question Identify the white section of a binary image

Detect contours. Cycle through contours and build rectangle, which contour fit.

Use some CV lib for this task, for example OpenCV (highly recommeded). You will need do something like that:

// contours of targets
std::vector<std::vector<cv::Point> > contours;

// get contours from binary image
cv::findContours(binImg,contours,CV_RETR_TREE,CV_CHAIN_APPROX_SIMPLE);

// poly contours
std::vector<std::vector<cv::Point> > contours_poly(contours.size());

// bounded rectangles
std::vector<cv::Rect> boundRect(contours.size());

for (int i=0; i<contours.size(); i++) {
    // get polyDPcontour and bound rectangle of it
        cv::approxPolyDP(cv::Mat(contours[i]), contours_poly[i], 3, true);
        boundRect[i] = cv::boundingRect(cv::Mat(contours_poly[i]));
}
2014-04-25 00:51:01 -0500 answered a question navfn planning through wall

Navfn works good for me and my drone (in the real flights) but i don't set footprint of robot. I set robot_radius parameter instead. You should try this, may be it will help.

P.S. On picture you provided i do not see any troubles with robot size. If obstacles are presented as black pixels, then pathfinding works correctly.

2014-04-23 01:58:15 -0500 commented question ros node misses data while subscribed to another node

it's hard to answer without looking at your code.

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2014-04-20 21:19:27 -0500 answered a question move_base without map

You have incomplete defenition for global costmap. If it is not static, then you have to define rolling_window=true and width, height and resolution parameters, as you do for local costmap.

2014-04-20 20:18:27 -0500 commented question Are there packages or libraries about sensors,for example laser,to accomplish the simulation?

But ROS is in fact consumer of device data, not provider. You want to simulate something, using ROS?

2014-04-20 20:13:09 -0500 answered a question Is gazebo a good simulator? Or are there any better ones?

Yes, you can use gazebo for drones. Take a look:

You have to create model and simple controller for your model. Take a look here for some examples: https://github.com/CrocInc/uav-croc-c...

I use standalone gazebo for my tasks.

Don't know, if V-Rep is better than gazebo or not. Will try V-Rep in near future.

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2014-04-15 23:13:26 -0500 commented question move_base costmap not updating or publishing GridCell topics

Can you show your launch file? BTW check if everything ok with odom frame.

2014-04-14 02:09:22 -0500 commented question How Extract Obstacle Information ?

It's hard to say why: cannot corellate rviz and sim images on https://www.dropbox.com/s/4bxzlid7e25mwuu/obstacle_remain.png. Can you add laser visualisation in rviz?

2014-04-14 02:01:29 -0500 commented question move_base costmap not updating or publishing GridCell topics

>>>"However when the robot moves close to an obstacle, the costmap doesn't update" How close? Or local costmap doesn't update at all?

2014-04-10 23:46:04 -0500 answered a question How Extract Obstacle Information ?

It's hard to say why: cannot corellate rviz and sim images on https://www.dropbox.com/s/4bxzlid7e25mwuu/obstacle_remain.png. Can you add laser visualisation in rviz?

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2014-04-09 22:05:26 -0500 answered a question How Extract Obstacle Information ?

cells.size() has int type.

Try use ROS_INFO("size: [%d]", msg->cells.size()); Not %f.

2014-04-09 08:33:43 -0500 answered a question How Extract Obstacle Information ?

msg->cells[] is one-dimensional array, as far as i see. So, if msg->cells.size() == 0, then there are no obstacles. If msg->cells.size()>0, then the last index of array == msg->cells.size()-1. In your code you always read first member in array (cells[0]).

2014-04-09 01:04:31 -0500 commented question How Extract Obstacle Information ?

msg->cells.size() ? You already have it in your code.

2014-04-08 21:04:26 -0500 commented question How Extract Obstacle Information ?

You have a problem with reading topic /move_base_node/local_costmap/obstacles? Is it epty or something else? Did not quite understand the question.

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2014-04-08 20:43:55 -0500 commented answer How to put headers into devel/include folder with catkin_make?

Thanks. That's was my folly: missed that find_package thing.

2014-04-08 06:17:14 -0500 asked a question How to put headers into devel/include folder with catkin_make?

Have a lib in my package and want to share its header.

According to "how-to" I use this command:

install(DIRECTORY include/${PROJECT_NAME}/
    DESTINATION ${CATKIN_PACKAGE_INCLUDE_DESTINATION})

But after "catkin_make" command no headers are in devel/include folder. (Lib itself successfully appears in /devel/lib folder)

When I run "catkin_make install" command headers appear in install/include folder properly.

What am i doing wrong?