add some evaluation stuff

diff --git a/marsrover/document/evaluation.tex b/marsrover/document/evaluation.tex
index a9aa80c..e7be3a1 100644 (file)
--- a/marsrover/document/evaluation.tex
+++ b/marsrover/document/evaluation.tex
@@ -73,7 +73,7 @@ and if they are we try to complete as many iterations as possible.
 \end{table}
 
 \subsection{Evaluation}
-\subsubsection{Realisation}
+\subsubsection{Requirements realisation}
 %implemented features and mission range
 The final implementation satisfies all the \emph{must have} requirements.
 Besides all the most important requirements it also supports all \emph{should
@@ -84,6 +84,7 @@ of that mapping and localization was not implemented. In the end of the process
 we had some time left which we used to implement \emph{ER2} since it was
 relatively simple.
 
+\paragraph{Mission range}
 The range of missions the robot can support is a lot bigger then reflected by
 the met functional requirements. All actions specifiable in a behaviour consist
 of atomic operations that take very little time leading to the action being
@@ -91,18 +92,47 @@ interruptible at all times. Together with the rudimentary variable storage we
 can make missions very complex. Possible combinations of behaviour can perform
 actions such as: counting, following moving objects and grouping objects.
 
-In the beginning of the running program, the user need to press any button to start 
-the program in the robot. This is because both bricks need to start the bluetooth 
-communication pairing at the same time. If we were given more time we would make 
-the bluetooth pairing automatically run from the beginning of the program without 
-waiting button press in order to limit the user involvement in the robot.
+One could argue that due to the lack of control structures it is very difficult
+to program complex missions. This is the case, for example if we would add a
+\emph{while} construction it would increase the range of missions very much.
+However, it also makes programming the robot much more difficult and will
+reduce the usability. With the current structure with the subsumption
+architecture and the rudimentary memory you actually can create such control
+structures but it takes a little more effort.
 
-The DSL can accomodate the improvement in the case of adding new sensors or actuators.
-For instance, if we want to add a new sensor, then it is easy to add new \emph{StoppingExpression}
-in the DSL. In addition, if we want to add a new actuator to the robot, we can just add
-a new action defined in the DSL and implement the use of the action in the program.
+\paragraph{Flexibility}
+The DSL can very easily be improved in the case of adding new sensors or
+actuators. For sensors we can just add clauses in the grammar within the
+\emph{StoppingExpression} that will process the values. For actuators the same
+thing can be done in the \emph{Action} rule. A change in the robot's
+configuration can also be handled very quickly albeit not in the DSL itself. We
+specifically chose not to incorporate the hardware configuration in the DSL to
+keep is a simple as possible and thus less error prone. This means that if the
+hardware configuration changes the underlying library must be changed as well.
+However, due to the modularity of the library this is very easy.
+
+\paragraph{Safety}
+The DSL by design does not generate \emph{safe} code implicitly. A programmer
+can make a program that can destroy the robot very easily. While safety is very
+important it would limit the range of missions a lot if some basic behaviours
+used in the demonstration for safety would be inherently present.
+
+\subsubsection{Development process}
+Booting the bricks takes around a minute to complete. When the robot is
+programmed launching the application takes another 30 seconds followed by
+another 30 seconds waiting on the initialization of the sensors. About once
+every 10 times on high battery and about every other time on low battery the
+ultrasonic sensor fails to initialize. We did not have the time to investigate
+this properly but the fault was hidden somewhere deep in the \emph{LeJOS} code.
+When all sensors were initialized the Bluetooth connection could be commenced
+by pressing a button on both bricks. Connecting via bluetooth has about the
+same error rate as the ultrasonic sensor has and takes about 30 seconds.
+
+This very long start up led to a rough development process with long feedback
+loops. After a long time we and other groups found out that applying power to
+the bricks during the initialization and pairing reduced the error frequency a
+lot.
 
-\subsubsection{Discussion}
 %development process, use of dsl/technologies, general lessons
 From our experience, the most important think in the development process was to 
 start working from a small functionality and to test it. As soon as we knew 
@@ -112,4 +142,4 @@ functionality. The difficulty in the development was in the testing phase. The
 reason was sometimes we got an error when running the program in the robot (for 
 example: sensor exception) and it took so much time for loading all sensors to be 
 ready for testing. Moreover, there was a time when the robot was crashed and needed 
-to be restarted which took some time from the development time.
\ No newline at end of file
+to be restarted which took some time from the development time.