| @@ -1,24 +1,32 @@ | |||
| %&tex | |||
| \chapter{Case study Method} | |||
| \chapter{Case Study: Method} | |||
| \label{chap:case_method} | |||
| The goal of this case study is to evaluta the design plan as presented in the previous chapter. | |||
| The evalutation is done by developing a system according to the design plan. | |||
| Ingeneral, the method of the case study follows all the steps of the design plan. | |||
| The goal of this case study is to evaluate the design plan as presented in the previous chapter. | |||
| The evaluation is done by developing a system according to the design plan. | |||
| In general, the method of the case study follows all the steps of the design plan. | |||
| Additionally, an evaluation protocol ensures that the development is evaluated consistently. | |||
| The last important thing is a subject of design that is developed in the case study. | |||
| The next sections present the evaluation protocol and the subject of design. | |||
| \section{Evaluation Protocol} | |||
| A survey is design to assess how the method is applied during the case study. | |||
| The survey specifies a list of questions. | |||
| All the questions will be adressed for each step in design plan. | |||
| Part of the questions will be answered before the step is performed. | |||
| The rest of the questions will be answered after the step is performed. | |||
| The questions are not soley to measure the effectiveness of the design method, but to investigate the usability as well. | |||
| To ensure the usable design plan, the step must feel intuitive and must not interfere with the workflow. | |||
| The evaluation protocol ensures that the different steps, decisions and changes of the design are consistently evaluated. | |||
| This protocol contains a questionnaire and model validation. | |||
| The full questionnaire is administered during each step in the design plan. | |||
| It covers questions about the design process as well as the design plan. | |||
| The model validation is performed at the end of the development. | |||
| This validation is done by creating a physical prototype of the design and comparing the operation with the designed model. | |||
| The duo questions, consisting of a before and after question are listed in \autoref{tab:prepost}. | |||
| The questions that focus on the design plan are listed in \autoref{tab:questionsmethod}. | |||
| \subsection{Questionnaire} | |||
| The questionnaire consists of two sets of questions. | |||
| The first set of questions is shown in \autoref{tab:prepost}. | |||
| This set consists of pairs of questions and focusses specifically on the execution of the design step. | |||
| Each pair embodies a theme, with one questions answered before, and the other question answered after the execution of the design step. | |||
| The goal of these pairs is to record the expected and planned execution with the results of the execution. | |||
| The second set of questions focusses on the described method of the design step. | |||
| These questions are shown in \autoref{tab:questionsmethod}. | |||
| To answer and record the questions consistently, there is a template document with these questions. | |||
| The document with the answers is stored in version control and is automatically typeset into a PDF document. | |||
| \begin{table*} | |||
| \caption{Table with questions to evaluate the steps. With corresponding questions ordered in pre and post step columns.} | |||
| @@ -38,13 +46,13 @@ The next sections present the evaluation protocol and the subject of design. | |||
| What is the protocol to review the result of this step? & How was the evaluation done? Did it reveal something new? \\ | |||
| \hline | |||
| \textbf{What is the expected workload?} & \textbf{Was the workload different than expected?} \\ | |||
| How many hours are required for the execution of the step? Also give a range in your incertainty. & How much time was invested in the step? Why was it more or less than expected? \\ | |||
| How many hours are required for the execution of the step? Also give a range in your uncertainty. & How much time was invested in the step? Why was it more or less than expected? \\ | |||
| \hline | |||
| \textbf{What is the expected result of the step?} & \textbf{Is the result as expected?} \\ | |||
| At the end of the step, what is the expected result? & Does the result match the description made prestep? Why does it not match? \\ | |||
| At the end of the step, what is the expected result? & Does the result match the description made pre-step? Why does it not match? \\ | |||
| \hline | |||
| \textbf{What is the expected feasibility?} & \textbf{Was the expected feasibility of the implementation accurated?} \\ | |||
| What are the problems you expect during implementation? Why? & Even if the implementation succeeded, the feasibility does not have to be 100\%. Give an estimate for the feasibility now that the implementation is finished. Explain the difference with the prestep feasibility.\\ | |||
| \textbf{What is the expected feasibility?} & \textbf{Was the expected feasibility of the implementation accurate?} \\ | |||
| What are the problems you expect during implementation? Why? & Even if the implementation succeeded, the feasibility does not have to be 100\%. Give an estimate for the feasibility now that the implementation is finished. Explain the difference with the pre-step feasibility.\\ | |||
| \hline | |||
| \end{tabular} | |||
| \end{table*} | |||
| @@ -66,78 +74,46 @@ The next sections present the evaluation protocol and the subject of design. | |||
| \end{tabular} | |||
| \end{table*} | |||
| \subsection{Reporting} | |||
| To answer all these questions and record all the steps a template was made. | |||
| This template is a markdown-document that contains all the questions. | |||
| The filled in documents will be stored in a git-repository. | |||
| With continuous integration the documents will be merged to a single pdf. | |||
| The development of the hardware will be done in a separate git repository. | |||
| Each step will have its own issue. | |||
| This issue has a description and a checklist for the evaluation. | |||
| Commits will be referenced to the issue, in that way all commits are grouped and can be tracked in the issue. | |||
| \subsection{Model validation} | |||
| The design plan focusses on the modelling of the system. | |||
| It is, however, not given that passing all the tests does also results in a working design. | |||
| If the tests are incomplete or complications in the design are overlooked, the design process is worthless. | |||
| Therefore, the model will be validated with a physical prototype of the design. | |||
| This shows whether the model is correct and whether all assumptions about the system are correct. | |||
| The prototype does not only show where the design process went wrong, it can also be used to improve the design plan to prevent these modeling problems. | |||
| \section{Subject of Design} | |||
| The choice in subject of design has a strong influence on the effectiveness of the evaluation of the design plan. | |||
| To ensure the best subject of design a list of requirements is composed. | |||
| Based on this list the best subject of design is a "Tweet on a whiteboard writer", which will be referred to as system. | |||
| Based on this list the best subject of design is a "Tweet on a whiteboard writer", which is referred to as system. | |||
| Other subjects were considered, but did not meet the desired requirements. | |||
| The most important requirement is that, while developing the system, the different aspects of the design plan are used. | |||
| Taking into account that there is a limited time budget and that the system must be within the scope of the design plan, the set of possible subjects of design is slim. | |||
| The time budget is set to 10 weeks of development and the system must have a dynamic system that can be controlled. | |||
| The time budget is set to 10 weeks of development and the system must have a dynamic system that is actuated via a software controller. | |||
| The tweet on a whiteboard fits within these requirement as it can have interesting dynamics and has multiple features. | |||
| Although the system could be seen as a simple wall plotter with simple XY-movement, it has alternative implementations that achieve more complex XY-movement. | |||
| %%%%%% Ligt toe dat er meerdere features zijn. | |||
| \subsection{Requirements} | |||
| The goal is to find a case study that can be used to evaluate the design method within a Master's Thesis. | |||
| Some requirements are defined to help the selection of a suitable case study. | |||
| To fit the design in the period of a Master's Thesis it should not require more than 10 weeks. | |||
| A fully-designed and constructed product is a nice result but is not required. | |||
| The case study can be terminated at the end of the period if all the elements of the design method have been sufficiently evaluated. | |||
| Although a finished product is not required, a partial prototype is part of the testing and validation procedure. | |||
| As the design method focuses on the physical component, a mechanical prototype is important. | |||
| The prototype would originally been constructed with the rapid prototyping facilities at the university. | |||
| However, the COVID-19 pandemic forced the university to close and to work from home. | |||
| This limited the rapid prototyping to DIY-tools and a 3D-printer. | |||
| To comply with the limited time and construction options it is tempting to go with a simple system. | |||
| Going for a simple system is not an option. | |||
| The goal of the design method is to reduce the complexity of the development. | |||
| Therefore, the case study should cover at least multiple features and interesting dynamics. | |||
| Multiple features allow for multiple design cycles. | |||
| Complex dynamics make multiple levels of detail possible. | |||
| \subsection{Tweet on a Whiteboard} | |||
| \label{sec:whiteboardwriter} | |||
| An example is for a system to be designed is a device that writes tweets on the white board. | |||
| That would be device that can write on white board. | |||
| This can be split in multiple features, with increasing complexity: | |||
| \begin{enumerate} | |||
| \item Moving the marker on the board: Simple XY-movement | |||
| \item Lifting the marker from the board: Z-movement | |||
| \item Erasing: End effector manipulation | |||
| \item Changing color: Switching Marker | |||
| \item Speed increase. | |||
| \item Direct input. | |||
| \end{enumerate} | |||
| Although it is possible that the system is seen as a simple wall plotter with simple XY-movement, there are alternative implementations that achieve more complex XY-movement. | |||
| This provides the required complexity and allows for different levels of detail needed for the variable detail approach. | |||
| The system can be split into more than one feature, which is required to evaluate the rapid development cycle. | |||
| One of the features is the XY-movement and other features are: | |||
| \begin{enumerate} | |||
| \item Lifting the marker from the board | |||
| \item Erasing: End effector manipulation | |||
| \item Changing color: Switching Marker | |||
| \item Speed increase | |||
| \end{enumerate} | |||
| Similar to the XY-movement, these features have multiple implementations that add complexity to the system. | |||
| This gives the possibility during the case study to go with a more or less complex design, allowing to fit the case study in the time budget without compromising the quality of evaluation. | |||
| The moving and change of color have multiple solutions, which satisfy the features requirement. | |||
| The complexity is also present in this example, the movement of the marker introduces multiple degrees-of-freedom. | |||
| Furthermore, the speed increase adds complexity as well. | |||
| The actuation of the system requires software. | |||
| However, instead of characters on the board it is possible to make basic figures, like squares and circles. | |||
| This minimizes the implementation of the software. | |||
| Although a finished product is not required, a partial prototype is part of the testing and validation procedure. | |||
| As the design method focuses on the physical component, a mechanical prototype is important. | |||
| The prototype would originally been constructed with the rapid prototyping facilities at the university. | |||
| However, the COVID-19 pandemic forced the university to close and to work from home. | |||
| This limited the rapid prototyping to DIY-tools and a 3D-printer. | |||
| It is expected that this set of tools is sufficient to construct a prototype of the tweet on a whiteboard system | |||
| \subsection{Decision} | |||
| The preferred case study is the whiteboard writer in \autoref{sec:whiteboardwriter}. | |||
| The Peg-in-Hole problem is mainly a control problem instead of a mechanical challenge. | |||
| Therefore the Peg-in-Hole problem disqualifies as a good case study for goal of this Thesis. | |||
| The RTK Calibration is a good case study. | |||
| However, as it is a calibration device it has to be accurate. | |||
| It is expected that this abstracts the complex dynamics from the design space. | |||
| Overall the whiteboard writer gave more possibilities and is also a better demo. | |||
| Sending a tweet to a robot has never been a bad demo. | |||
| Other options that were looked at was a 3D calibration system for a positioning system. | |||
| This idea was rejected because the complexity originated from the required accuracy instead of the dynamics. | |||
| In other words, choosing interesting dynamics would degrade the usability of the system. | |||
| A peg-in-hole problem, was also considered briefly as well. | |||
| But that is mainly a complex sensing and control problem, and not dynamically interesting. | |||