MASTER THESIS Robotics Engineering 30-08-2019

Code Documentation Thesis

Screenshots

Video of the final experiment

GitHub link video Streamable link video Same video uploaded twice if one does not work.

Workspace folders

src/peg (catkin package)

The "only kinematic" package, simulated with UWsim. Folder "toBeAdded_uwsim":

model & scenes subfolders in uwsim/data/scenes (along with default scenes and models)
terrain & objects in ~/.uwsim/data
src/peg_dynamics (catkin package) NOTE: not anymore in master. Maybe useful for future works?

Package with dynamics of vehicle and arm. The dynamics is provided by FreeFloatingGazebo, a plugin which use Gazebo and UWSim functionalities. Folder "tobeAdded_freeFloatDemo":

objects, terrain, scenes, urdf in src folder of freeFloatingGazebo_demo (Maybe also in .uwsim/data?)
lauch folder also in src folder of freeFloatingGazebo_demo, but maybe other launches can be written accordingly to peg_dynamics package.

matlab folder

matlab code for plotting test

model folder

folder needed by kdlHelper (inside the packages) to parse the robot model and build the jacobian (the KDLHelper).

Others?

TODO: better put as separate package various support/helper classes that have no differences for kineatic and dynamic version.

Code Schemes

Control Flow Scheme

Dependencies

Simulators

UWSim Undewater Simulator. the last version is the kinetic one (even if tutorial stop at the groovy version, it is only needed to follow it substituting groovy with kinetic).
FreeFloating Gazebo Plugin for gazebo and UWSim to introduce dynamics. It also contatin a dynamic controller (which I use) which can be use to "transform" position, velocity or force (it can be choosen the modality) to thruster and joints. Both the source (freefloating_gazebo) and the demo (freefloating_gazebo) are needed. NOTE not used anymore, maybe useful for future works?
Code

ROS kinetic, obviously. It is used not only to communicate with simulator, so also if other simulator is used (no UWSim or Gazebo), it is needed.
boost (already installed with ROS ??) the famous c++ library
eigen 3 c++ library to deal with matrices in a sort of matlab style. It contains also a geometry part (Transformation/Rotation matrix and so on) but I don't use it because of "geometrical" computations are done with CMAT.
CMAT (private? library of University of Genova) Needed for core of TPIK (regularized pseudoinversions)
kdl (should be already installed with ROS) parse urdf model of robots to get Manipulator Jacobian and position of end effector from the state (ie, angles) of joints
tf (already installed with default ros?) ros package to deal with transformations provided by the simulator (eg position of the vehicle respect world)
parse_urdf (already installed ros) to parse the urdf model (see kdl)

Vision part

opencv 3.4 (sudo apt install ros-kinetic-opencv, AND/OR normal installation following website) The core for all vision things
cv_bridge ros package to convert openCV images into ros message images and viceversa
image_transport (already included with default ros installation?) to deal with ros topics which share images
VISP 3.2 Visual Servoing Platform It is nicer to use than opencv when dealing with more robotic vision things like model based stereo tracking of an object
PCL

Solutions for some possible compiling issue:

eigen library not found

It may be cause by the fact that eigen is installed in a folder named eigen3 (and not eigen). Solution:

1 cd /usr/include #the folder where is eigen3

2 sudo ln -s /usr/include/eigen3/Eigen Eigen #create symbolic link

cmat_defines.h problem

in cmat there is a defined constant #define PI 3.14xxxx this is a problem because kdl library has a const int called PI. Solution is to change (in cmat_defines.h) : #define PI 3.14xxxxx in const int PI 3.14xxxxx

VISP_HAVE_PCL not setted

there is a function .track() in the tracker.cpp. This function is declared in a .h which has VISP_HAVE_PCL flag before. Even with pcl-ros installed, this flag can be unsetted. Solution? Not sure if I have broken all (at the moment is works, but be sure pcl is installed (ros-pcl is ok)), but I simply added

#define VISP_HAVE_PCL

in /opt/ros/kinetic/include/visp3/visp_modules.h

MISC

to add a task: CMAKE: add_library add target_link_libraries sia per task cpp sia metti sto task cpp come link al main

Libraries:

tf (to get transformation from ros) usata solo dal (rosInterface) che gestisce le cose ros.

cmat solo per computazioni pseudoinverse in icat eq e ican ineq, so nota solo alla classe controller che effettivamente fa ste operazioni. Indipendente da ros

eigen matrice di "passaggio" tra le due sopra. Usata anche per riempire le jacobiane nelle classi task (più comoda di cmat). Nota a TASKS e (main) ma non è un problema perchè è indipendente da ros, (installabile anche senza ros) controllore non la usa perchè usa solo cmat

kdl get jacobians from urdf models

the workspace chaining thing

https://answers.ros.org/question/205976/sourcing-from-multiple-workspaces/