Add documentation for Task and Features.

86ee5ecb · Florent Lamiraux · 5064297f · 86ee5ecb · 86ee5ecb · 86ee5ecb
Commit 86ee5ecb authored 12 years ago by Florent Lamiraux
--- a/doc/CMakeLists.txt
+++ b/doc/CMakeLists.txt
@@ -7,3 +7,7 @@ INCLUDE(../cmake/sphinx.cmake)

 SPHINX_SETUP()
 SPHINX_FINALIZE()
+INSTALL (FILES
+  pictures/feature.png 
+  pictures/task.png 
+  DESTINATION ${PKG_CONFIG_DOXYGENDOCDIR}/pictures)
\ No newline at end of file
--- a/doc/Doxyfile.extra.in
+++ b/doc/Doxyfile.extra.in
 INPUT                  = @CMAKE_SOURCE_DIR@/include \
                         @CMAKE_SOURCE_DIR@/doc/additionalDoc
-IMAGE_PATH             = @CMAKE_SOURCE_DIR@/doc/pictures
+IMAGE_PATH             = @PKG_CONFIG_DOXYGENDOCDIR@/pictures

 FILE_PATTERNS          = *.cc *.cpp *.h *.hh *.hxx

 TAGFILES               = \
 "@JRL_MAL_DOXYGENDOCDIR@/jrl-mal.doxytag = @JRL_MAL_DOXYGENDOCDIR@" \
 "@DYNAMIC_GRAPH_DOXYGENDOCDIR@/dynamic-graph.doxytag = @DYNAMIC_GRAPH_DOXYGENDOCDIR@"
+
+COLLABORATION_GRAPH    = NO
--- a/doc/additionalDoc/package.h
+++ b/doc/additionalDoc/package.h
@@ -4,19 +4,19 @@
 This library implements a modular architecture to test and experiment
 controllers in the Stack of Tasks Framework as defined in \ref Mansard2007.
 It is specifically targeted to retain real-time performance while
-having high level software capabilities, like plugins and scripts.
+having high level software capabilities, like plugins and python scripting.

 \section sec_organization Organization of the code

-The code is based on the dynamic-graph package, which provides the
-framework from which sot-core relies. Hence most of the code in sot-core
-consists of classes that derive from entities. These entities are usually
+The code is based on the <c>dynamic-graph</c> package, which provides the
+framework on which sot-core relies. Hence most of the code in <c>sot-core</c>
+consists of classes that derive from dynamic_graph::Entity. These entities are usually
 compiled and linked in their own dynamic library, as a python module

-Aside from the entities, there is a code base to the library, libsot-core,
+Aside from the python modules, this package installs a core library libsot-core,
 that provides functions and code common to all modules. All python modules
 developed here link with libsot-core. For example, common mathematical
-entities, definitions and functions are in that library's base.
+entities, definitions and functions are in the core library.
 See \ref sot_core_base for a list of what's in this code base.

 This library implements
@@ -27,16 +27,14 @@ This library implements
 \li A basic C++ "machinery", the \ref factory, that "makes things work"

 \section using Using the Stack of Tasks
-Using dynamic-graph objects (pool and factory), either through C++ code
-or the built-in interpreter, we can
-For people who develop software on the HRP2 robot, this package
+
+For people who develop software to control a real robot, this package
 alone is insufficient to simulate and control a robot.

 The following packages are recommended* in that case:
 \li sot-dynamic
 \li sot-pattern-generator
 \li sot-openhrp (openhrp python module)
-\li sot-openhrp-scripts

 * These packages are in development at the time of writing and may
 be separated or joined along the way. Please check their status and updates
@@ -47,28 +45,24 @@ at the jrl-umi3218 web page: https://github.com/jrl-umi3218
 This package should be compiled and installed with cmake.

 This library is based on several packages:
- \li dynamic-graph (https://github.com/jrl-umi3218/dynamic-graph)
- \li MatrixAbstractLayer (https://github.com/jrl-umi3218/jrl-mal)
- \li Lapack
- \li Boost
- \li pthread
+ \li <c>dynamic-graph</c> (https://github.com/jrl-umi3218/dynamic-graph)
+ \li <c>jrl-mal</c> (https://github.com/jrl-umi3218/jrl-mal)
+ \li <c>lapack</c>
+ \li <c>boost</c>
+ \li <c>pthread</c>

 Their presence will be checked with the use of pkg-config.

-There are talks of open-sourcing the library on github. When this
-is done, installation instructions will be on the project's github
-page.
-
-\section sot_base Base library
-This package is centered around a base library that implements
+\section sot_base Core library
+This package is centered around a core library that implements
 the basic classes needed for operation of the stack of tasks. For
 more information, see \ref sot_core_base.

 \section sot_plugins Python Modules
 While the main library provides a basic framework for computation of a
 control law using the Stack of Tasks, it is not expressive enough for
-typical usage scenarios (for example, controlling the humanoid robot
-HRP-2). Hence, several "specialized" features and tasks have been developed,
+typical usage scenarios (for example, controlling a humanoid
+robot). Hence, several "specialized" features and tasks have been developed,
 and can be used in the Stack of Tasks. For a list of python modules and a short
 description, see \ref plugins_list.

@@ -80,6 +74,14 @@ of tasks (SoT), and thus assigned a priority. The SoT then calculates
 (in an iterative manner) the control law, or joint velocity, necessary
 to realize the tasks (usually, bring a feature to its desired value).

+\subsection features Features
+Each feature computes some information
+from measurements, from the robot state,or/and
+from others features. Features should be lightweight
+regarding computation and be included at this level
+only if necessary. See documentation of class dynamicgraph::sot::FeatureAbstract
+for more information.
+
 \subsection tasks Tasks

 Each task implements a specific controller which
@@ -90,12 +92,7 @@ handling and its gain.
 After being defined, tasks are pushed in the Stack of Tasks which then
 calculates a control law as explained in \ref Mansard2007.

-\subsection features Features
-Each feature computes some information
-from measurements, from the robot state,or/and
-from others features. Features should be lightweight
-regarding computation and be included at this level
-only if necessary.
+See documentation of class dynamicgraph::sot::TaskAbstract for more information.

 \section References
 \anchor Mansard2007
@@ -107,14 +104,14 @@ IEEE Trans. on Robotics, 23(1):60-72, February 2007



-@defgroup sot_core_base Sot-core base library (libsot-core.[dll|so])
-For developers, this is the base library that your project has to
+@defgroup sot_core_base Sot-core library (libsot-core.[dll|so])
+For developers, this is the core library that your project has to
 be linked with. It defines the related algorithms and entities
 using the dynamic-graph framework.

 \section presento What's in the box?

-All the C++ code is placed in the namespace "sot". In the base
+All the C++ code is placed in the namespace "dynamic_graph::sot". In the core
 library, the following classes are present:

 \subsection subsec_sot Stack of Task solvers
@@ -142,25 +139,30 @@ strings, or set them from the command line (using a script interpreter from
 the dynamic-graph package).

 \subsection subsec_Features Features
-The class sot::FeatureAbstract is the base class for features.
+The class dynamicgraph::sot::FeatureAbstract is the base class for features.
 all other classes are in entity \ref sot_plugins "python modules".
-For more information on what is a feature, see \ref features.
+For more information on what is a feature, see the documentation of class dynamic_graph::sot::FeatureAbstract.

 \subsection subsec_Tasks Tasks
-They are a certain number of pre-written tasks that can be used.
-They all derive from the task sot::TaskAbstract; specific tasks
-are defined as \ref sot_plugins "python modules".
+
+Tasks are the hierarchical element of the stack of tasks.
+
+A task computes a value and a Jacobian as output signals.
+Once stacked into a solver, the solver will compute the control vector
+that makes the task value converge toward zero in the 
+order defined by the priority levels. For more information see the documentation
+of class dynamicgraph::sot:TaskAbstract.

 \subsection subsec_tools Mathematical base
 The following classes encapsulate common mathematical objects, and
-are all defined in the base library; see each individual class documentation
+are all defined in the core library; see each individual class documentation
 for reference.
 \li Vectors: (sot::VectorQuaternion, sot::VectorRollPitchYaw, sot::VectorUTheta)
 \li Matrices: (sot::MatrixForce, sot::MatrixHomogeneous, sot::MatrixRotation, sot::MatrixTwist)
 \li sot::MultiBound can be used to enforce bounds on numeric values

 \subsection subsec_others Others
-The base library also contains functions for adaptation and extension of
+The core library also contains functions for adaptation and extension of
 the dynamic-graph shell; see additional-functions.cpp, factory.cpp and pool.cpp
 directly for these. In a nutshell, a typical user shouldn't need these.
 See \ref factory for additional information.
@@ -168,7 +170,7 @@ See \ref factory for additional information.


 \defgroup plugins_list List of python modules
-These python modules are linked with the base library.
+These python modules are linked with the core library.

 	sot/sot-qr
 	sot/weighted-sot

--- a/doc/pictures/feature.fig
+++ b/doc/pictures/feature.fig
+#FIG 3.2  Produced by xfig version 3.2.5b
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+	 3797 679 4595 679
+4 1 0 50 -1 2 13 0.0000 4 150 1470 2775 1035 FeatureAbstract\001
+4 2 0 50 -1 0 11 0.0000 4 135 690 1664 900 selection\001
+4 0 0 50 -1 0 11 0.0000 4 135 765 3885 1301 dimension\001
+4 0 0 50 -1 0 11 0.0000 4 180 630 3885 945 jacobian\001
+4 0 0 50 -1 0 11 0.0000 4 90 360 3885 591 error\001
+-6
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+6 540 4950 7380 6795
+6 540 5535 2115 6075
+6 630 5535 1845 5850
+4 2 0 50 -1 0 22 0.0000 4 255 1170 1823 5813 errordot\001
+-6
+2 1 0 1 0 7 50 -1 -1 0.000 0 0 -1 1 0 2
+	1 1 1.00 110.67 221.33
+	 578 5979 2072 5979
+-6
+6 5805 4995 7380 5535
+6 5895 4995 7110 5310
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+	1 1 1.00 110.67 221.33
+	 578 6726 2072 6726
+4 2 0 50 -1 0 22 0.0000 4 180 705 1823 5149 error\001
+4 2 0 50 -1 0 22 0.0000 4 330 1230 1823 6560 jacobian\001
+4 1 0 50 -1 2 26 0.0000 4 300 2955 3898 5481 FeatureGeneric\001
+4 0 0 50 -1 0 18 0.0000 4 195 1335 2487 5951 errSOUT =\001
+4 0 0 50 -1 0 18 0.0000 4 195 2685 2487 6320 errorSIN - ref.errorSIN\001
+4 0 0 50 -1 0 18 0.0000 4 255 2205 2487 6726 jacSOUT = jacSIN\001
+-6
+2 2 0 1 0 7 50 -1 -1 0.000 0 0 -1 0 0 5
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+-6
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+4 2 0 50 -1 0 22 0.0000 4 255 2520 8681 6983 articularJacobian\001
+4 2 0 50 -1 0 22 0.0000 4 330 1230 8681 7730 jacobian\001
+4 2 0 50 -1 0 22 0.0000 4 330 1170 8681 6319 position\001
+4 1 0 50 -1 2 26 0.0000 4 300 2940 10756 6651 FeaturePoint6d\001
+-6
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+4 2 0 50 -1 0 22 0.0000 4 255 1305 4977 3182 selection\001
+4 0 0 50 -1 0 22 0.0000 4 255 1545 9127 3929 dimension\001
+4 0 0 50 -1 0 22 0.0000 4 330 1230 9127 3265 jacobian\001
+4 0 0 50 -1 0 22 0.0000 4 180 705 9127 2601 error\001
+4 2 0 50 -1 0 22 0.0000 4 255 1365 4977 2186 reference\001
--- a/doc/pictures/feature.png
+++ b/doc/pictures/feature.png
--- a/doc/pictures/task.fig
+++ b/doc/pictures/task.fig
+#FIG 3.2  Produced by xfig version 3.2.5b
+Landscape
+Center
+Metric
+A4      
+100.00
+Single
+-2
+1200 2
+6 3555 360 8820 2475
+6 7290 810 8820 1980
+2 1 0 1 0 7 50 -1 -1 0.000 0 0 -1 1 0 2
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+4 0 0 50 -1 0 22 0.0000 4 330 1230 7462 1735 jacobian\001
+4 0 0 50 -1 0 22 0.0000 4 255 600 7462 1071 task\001
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+4 1 0 50 -1 2 26 0.0000 4 300 915 6058 3906 Task\001
+4 2 0 50 -1 0 22 0.0000 4 255 1755 3983 3574 controlGain\001
+4 2 0 50 -1 0 22 0.0000 4 330 2010 3983 4238 dampingGain\001
+4 2 0 50 -1 0 22 0.0000 4 255 2385 3983 4985 controlSelection\001
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+4 0 0 50 -1 0 22 0.0000 4 255 2985 8235 4230 errorTimeDerivative\001
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+4 2 0 50 -1 0 22 0.0000 4 255 1245 3983 7084 errorDot\001
+4 0 0 50 -1 0 22 0.0000 4 255 1245 8235 7084 errorDot\001
--- a/doc/pictures/task.png
+++ b/doc/pictures/task.png
--- a/include/sot/core/feature-abstract.hh
+++ b/include/sot/core/feature-abstract.hh
@@ -52,38 +52,44 @@ namespace dynamicgraph {

      In short, a feature is a data evolving according to time.  It is defined
      by a vector \f${\bf s}(t) \in \mathbb{R}^n \f$ where \f$ t \f$ is the
-      time.  By default a feature has a desired \f${\bf s}^*(t) \f$.  The
+      time.  By default a feature has a desired \f${\bf s}^*(t) \f$.
+      \f${\bf s}^*\f$ is provided by another feature of the same type called
+      reference. The
      feature is in charge of collecting its own current state.  A feature is
      supposed to compute an error between its current state and the desired
      one: \f$ e(t) = {\bf s}^*(t) - {\bf s}(t) \f$.  A feature is supposed to
      compute a Jacobian according to the robot state vector \f$ \frac{\delta
      {\bf s}(t)}{\delta {\bf q}(t)}\f$.

-      \bigskip
-      More precisely, a feature is a derivable function of the robot
-      configuration $q$ and the universe \f$\Omega\f$ into a real vector space:
-      \f$ f: q,\Omega \rightarrow f(q,\Omega) \in R^n\f$. The object is able to
-      compute the value, and the value of the Jacobian of \f$f\f$ with respect
-      to \f$q\f$, \f$J = \frac{\partial f}{\partial q}\f$.
-
      The task is in general computed from the value of the feature at the
-      current instant \f$f(q(t),\Omega(t))\f$, the Jacobian \f$J\f$ and
-      evolution of the feature with the evolution of the universe, abusively
-      denoted as a variation along the variable \f$t\f$ alone: \f$\frac{\partial
-      f}{\partial t} = \frac{\partial f}{\partial \Omega} \dot{\Omega}\f$.
-
-      In general, the feature is computed as the error \f$f = e(q,\Omega)\f$
-      between the value at the current robot and universe configurations
-      \f$s(q,\Omega)\f$, and a reference value that does not depend on the robot
-      current configuration, and thus that is generally denoted \f$s^* = s^*(t)\f$.
-      In general, \f$s\f$ and \f$s^*\f$ evolves in the same space, and thus, two
-      objects of the same classes are used to represent \f$s\f$ on one side and
-      \f$s^*\f$ on the other. A generic solution to maintain a reference on the
-      object \f$s^*\f$ from the object \f$s\f$ is provided, but is not mandatory. In
-      that cases, the signal errorSOUT is linked to the update state
-      of the input of \f$s\f$, and is also automatically linked to the input of
-      \f$s^*\f$ as soon as \f$s^*\f$ is specifified.
-
+      current instant \f$f(q(t),t)\f$, the Jacobian \f$J\f$ and
+      evolution of the feature with respect to time: \f$\frac{\partial
+      f}{\partial t}\f$.
+
+      \par Time derivative of the error
+
+      Some Feature types provide as output signal the derivative of the
+      error of the feature (<c>errordotSOUT</c>). The value is computed by
+      method computeErrorDot. In this case, these feature types should
+      \li have attribute
+      \code
+      dg::SignalTimeDependent< ml::Vector,int > errordotSOUT;
+      \endcode
+      \li implement method
+      \code
+      virtual bool withErrorDot() const { return true; }
+      \endcode
+      \li implement method
+      \code
+      virtual SignalTimeDependent<ml::Vector,int>& getErrorDot()
+      {
+      return errordotSOUT;
+      }
+      \endcode
+
+      See dynamicgraph::sot::FeatureGeneric for an example.
+
+      \image html pictures/feature.png "Feature diagram: Feature types derive from FeatureAbstract. Each feature has a reference of the same type and compute an error by comparing errorSIN signals from itself and from the reference." width=15cm
    */
    class SOT_CORE_EXPORT FeatureAbstract
      :public Entity
@@ -191,8 +197,7 @@ namespace dynamicgraph {
      /*! \brief This method write a graph description on the file named FileName. */
      virtual std::ostream & writeGraph(std::ostream & os) const;

-      /*! \brief Return true for children that implements the errordot
-          functionalities. */
+      /// Return true for children that provide the errordot output signal
      virtual bool withErrorDot( void ) const { return false; }
      virtual SignalTimeDependent<ml::Vector,int>& getErrorDot( void ) {throw;}


--- a/include/sot/core/task-abstract.hh
+++ b/include/sot/core/task-abstract.hh
@@ -48,6 +48,15 @@ namespace dynamicgraph {
  namespace sot {
    namespace dg = dynamicgraph;

+    /// Hierarchical element of the stack of tasks.
+    ///
+    /// A task computes a value and a Jacobian as output signals.
+    /// Once stacked into a solver, the solver will compute the control
+    /// vector that makes the task values converge toward zero in the 
+    /// order defined by the priority levels.
+    ///
+    /// \image html pictures/task.png "Task diagram: Task types derive from TaskAbstract. The value and Jacobian of a Task are computed from the features that are stored in the task.
+
    class SOT_CORE_EXPORT TaskAbstract
      : public dg::Entity
    {