added path 2 for eval instead path 3

This commit is contained in:
toni
2016-05-09 15:04:37 +02:00
parent 89f764e22f
commit 5a3677e139
42 changed files with 18072 additions and 13 deletions

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@@ -88,9 +88,15 @@ We deployed 10 MC runs using \SI{2500}{} particles for approximation and a multi
Now, the positional average error along all 4 paths using the Nexus and the Galaxy could be improved from \SI{2.08}{\meter} to \SI{1.37}{\meter}.
Using the same number of particles and $500$ sample realisations the BS performs with an average error of \SI{2.21}{\meter} for filtering and \SI{1.51}{\meter} for smoothing.
The difference between both filtering steps is of course based upon the randomized behaviour of the respective probabilistic models.
It is interesting to note, that the positional error is very similar for both used smartphones, although the approximation error varies greatly as we will see later.
It is interesting to note, that the positional error is very similar for both used smartphones, although the approximation error varies greatly.
Using the FBS, the Galaxy donates an average approximation error of \SI{4.03}{\meter} by filtering with \SI{7.74}{\meter}.
In contrast the Nexus 6 filters at \SI{5.11}{\meter} and results in \SI{3.87}{\meter} for smoothing.
The BS has a similar improvement rate.
A visual example of the smoothing outcome for path 3 is illustrated in fig. \ref{fig:int_path3_a}.
It can be clearly seen, how the smoothing compensates for the faulty detected floor change using future knowledge.
The estimation of BS looks way more realistic and adapts better to the ground truth path.
%However, in this particular example the FBS starts at an earlier position (cf. fig. \ref{fig:intcomp} seg. 2), better handling the initial uniform distribution.
%Another advantage of BS over FBS, is the ability to still improve the filtering results even while reducing the number of particles radical.
@@ -98,16 +104,16 @@ The estimation of BS looks way more realistic and adapts better to the ground tr
\begin{figure}
\begin{subfigure}{0.175\textwidth}
\input{gfx/eval/interval_path3_good/path3_interval_good}
\input{gfx/eval/interval_path2_good/path2_interval_good}
\caption{}
\label{fig:int_path3_a}
\label{fig:int_path2_a}
\end{subfigure}
\begin{subfigure}{0.175\textwidth}
\input{gfx/eval/interval_path3_bad/path3_interval}
\input{gfx/eval/interval_path2_bad/path2_interval}
\caption{}
\label{fig:int_path3_b}
\label{fig:int_path2_b}
\end{subfigure}
\caption{a) Exemplary comparison between BS (blue) and filtering (green) using 2500 particles and 500 sample realisations. b) A situation where BS smoothing was not able to improve the filtering results. Two main factors are causing this: an initial position within a detached room and inaccurate pressure readings given by the Galaxy S5.}
\caption{a) Exemplary results for path 2 where BS (blue) and filtering (green) using 2500 particles and 500 sample realisations. b) A situation where BS smoothing was not able to improve the filtering results. Two main factors are causing this: an initial position within a detached room and inaccurate pressure readings given by the Galaxy S5.}
\label{fig:int_path3_comp}
\end{figure}
Despite the very good outcomes provided by both interval smoother, there are some rare situations in which smoothing does not improve the filtered estimation or even improves the visual path.
@@ -118,6 +124,9 @@ This shows that the smoothing results are of course highly depend upon the filte
At next, we discuss the advantages and disadvantages of utilizing FBS and BS as fixed-lag smoother.
Compared to fixed-interval smoothing, timely errors are now of higher importance due to an interest on real-time localization.
Especially interesting in this context are small lags $\tau < 10$ considering filter updates near \SI{500}{\milli\second}.
%Path 4 grafik mit fixed-lags
%
%wie gut ist fixed-lag mit einem lag = 5. was fällt so auf?
Fig. \ref{fig:lag_error_path4} illustrates the different approximation errors alongside path 4 using $500$ particles, \SI{100}{sample realisations} for BS and a fixed-lag $\tau = 5$.