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\chapter{Conclusions and Future Work}

{In this final chapter, the conclusions of this work and suggestions to keep improving this work will be explained in the next two sections, respectively.}
\section{Conclusions}
{ This work was composed by three main objectives. The first objective was to developed an haptic interface for the right tele-operation of the humanoid robot. This objective was accomplish with success. Using one of the most important characteristic of the \acs{ROS} environment, its modular characteristics, a new firmware interface was created to control the humanoid robot in different tasks. This new interface can be generalized and with small alterations applied to other tasks.\paragraph{} The second objective was to study and treat the different conditions that can interfere with the control of the humanoid robot by the human operator. This objective was divided into two parts: Study and treatment of the data responsible for controlling the humanoid robot and the force rendering problem. This objective was done successfully, although some improvements can be added to achieve better results (see Future Work section). The filter applied to the data before the transformation into angle values allows that the desired action is actually executed and in cases of unexpected noise, the robot is protected. To solve the force rendering problem, one force function was created, this new force show capabilities and can be an improvement to the human operator.\paragraph{} The last objective of this work was to validate and prove that the use of force feedback can be an improvement for tele-operation. The two experiments, using the fanuc, prove that with force feedback the path done by the robot is more constant and stable than the one done using only vision feedback.\paragraph{} Using haptic devices with force feedback to control humanoid robots presents in this way a good solution to retrieve valid data to be used in the next major step, Learning by Demonstration.
}
\section{Future Work}
{This work can be considered as a preparatory step to achieve the ultimate goal of an autonomous humanoid robot with learning abilities. Before this is possible several other steps and improvements are required, such as:}
\begin{itemize}
\item \textbf{Systematic and repeated experiments:} The preliminary results achieved with a real humanoid robot are promising and relevant, even if the methodology has much to be explored. In particular, systematic and repeated experiments with different subjects are needed since the success of the haptic teleoperation system is highly related with the user's experience.
\item \textbf{Force generation:} Currently, the force feedback used in all experiments is based on the COP calculated from the load cells in the feet. Since the humanoid robot has available a set of inertial sensors, it would be interesting to include this sensorial information (complementary) when synthetizing the forces relayed to the human operator.
\item \textbf{New scenarios and tasks:} In this work, only simple tasks involving balance were tested. Exploring new scenarios towards more challenging tasks (\textbf{e.g.,} biped locomotion with two Phantom Omni joysticks) are within the next goals.   
 \item \textbf{Learning algorithm:} The next logic step is to use the recorded datasets to apply a learning algorithm that can help in developing sensorimotor strategies for humanoid behaviour without a \textit{priori} rigorous models.  
\end{itemize}

%{This thesis began to prove the utility of using tele-operation to obtain better paths in balance. Now, the next logic step is to use the data obtained to apply and study the effect of using learning algorithms. In this way, will be possible to test different algorithms, and for example, it will be possible to compare the behaviour of the human operator with the behaviour of the machine.}
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%\subsection{Sensors}
%{All force generation and tests were based in the COP calculated by the Load Cells. Since there is available a set of inertial sensors implemented in the humanoid robot for future work would be interesting to add the data of this sensors, to help generating the new forces and be an additional assistance when the learning algorithm is applied.}
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%\subsection{Motion}
%{In this work, only the balance of the humanoid robot has been tested, it is interesting to study now and prepare the humanoid robot to perform tasks such as motion, using, for example, two Phantom Omni joysticks and retest the validity of this experiments to apply learning algorithms.
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