ANRO summer school

h1. Lab 3:  Forward kinematics

h2. Scope:

This laboratory consist of two parts:

* A short introduction.

* Writing your own ROS package.

h2. The task:

* Develop the system from the previous laboratory by either copying the package or modifying it.

* Using C++ or Python create a ROS node NONKDL_DKIN that calculates forward kinematics of manipulator using analytical method (without KDL).

  * The node gets current position of joints from joint_state_publisher node.

  * The result (i.e. position of end effector of type geometry_msgs/PoseStamped) should be published on ROS topic and visualized in RVIZ.

  * Do not interpolate movement.

  * Please refer to RVIZ documentation http://wiki.ros.org/rviz/Tutorials

  * Read parameters (e.g. lengths of links) from ROS parameter server.

  !lab3-scheme-a.png(graph a: ROS nodes for ANRO laboratory 3)!

* Create a second node KDL_DKIN that uses KDL, with the same functionality as NONKDL_DKIN.

  * Connect it to existing nodes in place of NONKDL_DKIN.

  !lab3-scheme-b.png(graph b: ROS nodes for ANRO laboratory 3)!

* Test the results in RVIZ. Compare nodes NONKDL_DKIN and KDL_DKIN with data from robot_state_publisher.

  * Check if the calculated pose is the same as the pose calculated by robot_state_publisher. Compare the poses in RVIZ.

  * All three nodes that calculate forward kinematics should publish to different topics.

  * Reference frames of the end effector should coincide. Set different visualization parameters (e.g. width, length of arrows) to see them all.

  * The documentation of tests should be supplemented with plots of end effector position calculated using different methods and plots of configuration space position.

        !lab3-scheme-c.png(graph c: ROS nodes for ANRO laboratory 3)!

* Joint limits should be taken into account.

  * If joint position is outside limits, the pose of end effector should not be published and error should be published to ROS log.

* Add wiki page to your repository (the documentation). The page should contain description of source files, instruction for launching and description of tests.

* Use separate roslaunch files for:

  * roscore and RVIZ (it should be running until URDF file is modified).

  * The rest of the system.

* Test the system and show it to the tutor.