how to rotate a point(x,y) about a fixed point
I want to rotate a point (x,y) from an orientation alpha to a new point(x,y) with an orientation beta about a fixed point (centre of the circle). How to do it in ROS ?
View Articleviso2 tf_tree problem
Hello to everybody. I want to use the mono odometer from vo for Odometry in the robot_localization. The first step which is allready not working is the vo. I always get the following error message:...
View ArticleHow to transform between the quaternions ( or ERYs)
I know I can transform my quaternion to ERY, and it seems easier to transform between ERYs because it's more direct. For example, I have a vector X (x,y,z) and its ERY is (0,0,a), and I have another...
View ArticleConfusing tf transforms
I have been working a lot with transform matrices these days and the tf nomenclature doesn't make things easier. For tf_echo, the input frames are defined as such: tf_echo When using Python and looking...
View Articlear_pose : interprete output of 'ar_pose_marker' && transform
Hello. I want to track a object that is moving inside a room and color the pixel in the cam-image, where the object has moved to. Instead of detect colors etc. I want to do this with markers from...
View ArticleGmapping tf problem
Hi, We are having problems with Gmapping. We are using a OMD10M-R2000 range finder and are getting odometry via RS232 from the robot. In RViz we get the following error: `No transform from [] to...
View ArticleWhy transform has to be broadcasted periodically?
Hello, Nowadays I am trying to build a mobile robot with several sensors, and be curious about using relative positions of sensors in ROS. In several tutorials, every transform(in my case, sensors)...
View ArticleHow is the orientation of tf /odom initialized?
What determines the orientation of the tf frame /odom when it is initialized? On the page for GPS integration, [here](http://wiki.ros.org/robot_localization/Tutorials/GPS%20Integration). It says: "The...
View Articlertabmap no work (only xtion) -- odometry : could not get transform from...
hello .. i follow rtabmap-ros tutorial. but program dont work. http://wiki.ros.org/rtabmap_ros/Tutorials/HandHeldMapping i only use xtion (openni2). no odmoety no laser. and i command line roscore...
View Articlertabmap_ros how to set odometry and camera?
Hello i try to xtion, kobuki(2 wheel mobile robot). i read http://wiki.ros.org/rtabmap_ros/Tutorials/SetupOnYourRobot. and apply my launch. i modify...
View ArticleHow to change the co-ordinates of the velodyne point cloud data?
 Hi, I have three velodynes and I launch all the three using group. I get the point cloud but all of them have the same...
View Articlemore than one odom->base_link transform
Hi, I have 2 nodes from third parts, both of them publish odom->base_link transform. I want to combine these 2 transforms and publish my own odom->base_link transform, since our navigation node...
View ArticleI need your advice, please (planar laser to 3D using encoder)
Hello everyone, I am using Neato XV-11 Lidar with getSurreal Lidar Controller v1.2 (Teensy 2.0). I have an Intel Edison (Flashed with Emutex's Ubilinux), and I am trying (unsuccessfully, but that's not...
View Articletf setup for sensor on a gimbal on a robot.
I looked through the [tf setup](http://wiki.ros.org/navigation/Tutorials/RobotSetup/TF), but it only show updating tf for a fixed system at arbitrary 1Hz interval. Anyways, I plan on using sensor...
View Articlenavigation transform information problem
Hello ! I try to run the navigation stack with a real robot (move_base + gmapping). My problem is that when I launch my launch file which is supposed to run the move_base node and the slam_gmapping...
View ArticleHow is tf data handled by velodyne_driver?
Hello, I am going to use a Velodyne VPL16 along with the velodyne_driver to publish a PoinCloud2 message to ROS. I have seen that the velodyne_node has the velodyne's frame_id as a parameter and I...
View ArticleFind coordinates of point in a different coordinate frame
Hi, I would like to know the easiest ROS way (tf, geometry_msgs or something of the sort) to get the coordinates of a point in another coordinate frame defined by a pose. Let's say, I have a point w...
View ArticleTransformation in Quaternion space for Geometry_msgs/poseStamped message
Hi, I am new to ROS and RTT. Given the Geometry_msgs/poseStamped message from two topics, how to calculate the transform T (Relative position) at time t1. T^t1 = Relative_position (Pose_1^t1,...
View ArticleExtract robot position from rosbag
I recorded tf-messages (while driving the robot) into a bagfile and wrote a ros node that should extract the positions (base_link-frame) from that bag file. My idea was to use a tf::Transformer and...
View Articletransform composition in tf with python
Hello In C++, it is possible to have transform composition to determine a relative transform between two transforms like follow: tf::Transform relative_transform = init_transform.inverse() *...
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