\loremipsum
\end{Abstract}
-The common description of our world is geometric.
-At human-scale, physicians model it with four dimensions: three dimensions in space and the fourth one is time.
-Therefore, movements are the elementary objects of such a space.
-They are 3d points that evolve in time.
-Thus, movements are essential in our understanding of our environment.
-One can wonder if movement is an essential part of the exploration of our environment because of this movement nature of the world, or at the contrary if our description of the world is geometric because it is the base of most of our perceptions.
-This question will remain open.
-However we will discuss here the
-
+% The common description of our world is geometric.
+% At human-scale, physicians model it with four dimensions: three dimensions in space and the fourth one is time.
+% Therefore, movements are the elementary objects of such a space.
+% They are 3d points that evolve in time.
+% Thus, movements are essential in our understanding of our environment.
+% One can wonder if movement is an essential part of the exploration of our environment because of this movement nature of the world, or at the contrary if our description of the world is geometric because it is the base of most of our perceptions.
+% This question will remain open.
+% However we will discuss here the
+
+In the previous chapter we discussed haptics as the sense of touch.
+This is the common interpretation of the word “haptic”.
+However haptics also refers to our ability to touch and manipulate.
+%In the context of interactive systems, this refers to inputs.
+In this chapter we will focus on touch and manipulation with the fingers, hands and arms.
+%Most of input modalities require touch and manipulation.
+It covers most of the commonly used input modalities: button, pointing interfaces, touch, and gestural interaction.
+All these modalities rely on gestures, but they leverage different parameters.
+Typically, buttons only sense binary contacts regardless of which finger pressed it, or the force or speed of actuation.
+Pointing iterface such as mice or touchpads sense 2D movements in addition to contacts.
+Multi-touch interfaces can even sense contacts and movements of several contact points.
+Finally, gestural interaction can be sensed in 3D in the air without contact.
+
+%All these modalities leverage our ability to touch and manipulate.
+%We will therefore discuss these types of input, and exclude other modalities such as voice input or brain-computer interfaces.
+%Including these modalities under the global term “haptic” may seem far-fetched to the reader.
+%My hope is that skeptical readers will agree it makes sense at the end of the manuscript.
+
+The relation between gesture input in the broad sense and haptics may seem far-fetched at first sight.
+However, if we look at \reffig{fig:hapticpath} and swith the user and the system, we obtain the \reffig{fig:inputpath}.
+The user produces a mechanical effect that the system will sense and interpret.
+Therefore the user will play the same role than a haptic device.
+With this in mind, this is not surprising that cognitive scientists call this phenomenon output, as opposed to input for computer scientists.
+The \reffig{fig:hapticpath} depicts both the user and the system, which both have a hardware part, in the physical world and a software part.
+The software part of users corresponds to ideas, or the mind in general, whereas the sotware part of the system refers to the code and its execution.
\begin{figure}[htb]
\centering
\node[anchor=south, minimum width=\textwidth,minimum height=25mm, inner sep=0,fill=black!10, outer sep=0](thebar3) at (0,1.35) {};
\node[anchor=south, minimum width=\textwidth,minimum height=.75mm, inner sep=0, outer sep=0](thebar3) at (0,3.25) {\textbf{Physical World}};
\matrix[row sep=1.25cm, column sep=7mm,inner sep=0, node distance=0, outer sep=0mm] (cells) {
- \labelcell{biopsycho}{Biology\\Psychology} & \redcell{motor}{Motor\\system} & & & \bluecell{mechanics}{Sensing\\System} & \labelcell{elecmeca}{Electronics\\Mechanics}\\
- \labelcell{ergocs}{Ergonomy\\Movement Sciences} & \redcell{movement}{Cognitive\\system} & & & \bluecell{software}{Software\\Controller} & \labelcell{csmath}{Computer Science\\Mathematics}\\
+ \labelcell{biopsycho}{Biology\\Movement Sciences} & \redcell{motor}{Motor\\system} & & & \bluecell{mechanics}{Sensing\\System} & \labelcell{elecmeca}{Electronics\\Mechanics}\\
+ \labelcell{ergocs}{Ergonomy\\Psychology} & \redcell{movement}{Cognitive\\system} & & & \bluecell{software}{Software\\Controller} & \labelcell{csmath}{Computer Science\\Mathematics}\\
& \labelcell{action}{Action} & & & \labelcell{info}{Information} \\
};
\draw [->, -stealth', thick] (action.north) -- (movement.south) node [midway, left] {Intention};
- \draw [->, -stealth', thick] (movement.north) -- (motor.south) node [midway, left] {Command};
+ \draw [->, -stealth', thick] (movement.north) -- (motor.south) node [midway, left] {Execution};
\draw [->, -stealth', thick] (motor.east) -- (mechanics.west) node [midway, above] {Physical};
\draw [->, -stealth', thick] (motor.east) -- (mechanics.west) node [midway, below] {effect};
\draw [->, -stealth', thick] (mechanics.south) -- (software.north) node [midway, right] {Signal};
\label{fig:inputpath}
\end{figure}
+\paragraph{Motor system}
+
+\paragraph{Input systems}
+
+The purpose of the modalities mentioned above is essentially sensing and interpreting gestures of the fingers, hands and arms.
+This is a much more complex task that it seems at first sight.
+The hand alone has 27 degrees of freedom~\cite{elkoura03}.
+It is not surprising that input systems only sense a tiny part of the
+
+Buxton collection of interactive devices\footnote{\href{https://www.microsoft.com/buxtoncollection}{https://www.microsoft.com/buxtoncollection}}
+
%Pseudo haptics \cite{lecuyer01}
\section{Research questions}
projects / hdr.git / commitdiff