2D and 3D Visualization to Support Fieldwork in the Area of Utility Networks

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IN

DEGREE PROJECT CIVIL ENGINEERING AND URBAN MANAGEMENT,

SECOND CYCLE, 30 CREDITS STOCKHOLM SWEDEN 2017,

2D and 3D Visualization to Support Fieldwork in the Area of Utility

Networks

KLAS GUSTAFSSON

OSKAR BERG

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Abstract

Utility network fieldworkers of today want to access more information and can benefit a lot from new technical development. Today most fieldwork is conducted using paper plans or locally stored data on laptops as a visual aid. Therefore there is a need for improvement and development of new reliable software for fieldwork. Also the ability to use advanced Geographic Information Systems (GIS) solutions and enhanced visualization methods while out in the field could help improve fieldwork. In order to be as e↵ective as possible when carrying out di↵erent tasks in the field, di↵erent ways of visualizing the same network data are required. 2D and 3D visualization methods have di↵erent advantages and disadvantages when it comes to visualizing network data, which will be accounted for in this thesis.

There are three main objectives in this thesis. The first is to evaluate how suitable di↵erent visualization methods are for fieldwork users working with utility networks.

The second is to get a better understanding of what hardware and software that can be used for implementing the visualization methods. The last one is to use the first and second objectives to develop a prototype for utility network fieldwork.

To address the objectives, the first step is to understand the users that work in the field. By conducting interviews, information about the current workflow for fieldworkers and their opinions about how the systems currently work is gathered.

Based on this information the thesis is divided into cases and criteria which is the foundation for proposing a solution in form of mock-up sketches which is then implemented in form of a prototype. Finally the prototype is evaluated quantitatively and qualitatively using a web survey and presentations for potential end users.

The prototype is created using web technologies and is mainly intended for tablets.

Because of its mobility, screen size and adequate computational power the tablet is a good hardware choice for conducting fieldwork. The prototype presents network data in a 2D interactive map view, a 3D augmented reality (AR) view and a combined view. These choices are based on information gathered by studying related work and performing interviews with potential end users in the beginning of the study.

The results of the thesis highlights large possibilities in making field work more e↵ective for fieldworkers. This in concluded partly by the results of the interviews with potential end users, but also by the response of the survey and presentation of the suggested solution. It is shown that there are new ways to improve the work process out in the field and that AR can help in visualizing the network in a new informative way for fieldwork. However, several challenges remain, but rapid techno- logical development implies possible solutions to deal with these challenges.

Keywords: GIS, Open Source, Fieldwork, Utility Networks, Augmented Reality

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Acknowledgements

Ella Syk, Digpro AB, co-supervisor. For always being there when needed, asking the right questions and keeping us on track.

Gyözö Gidófalvi, KTH Geoinformatics, supervisor. For swift and great feedback.

Johan Lars´en, Digpro AB, senior-supervisor. For finding interviewees and contributing with task-related knowledge.

Christer Folkesson, Digpro AB. For the endless technical support.

Fredrik Hilding, Sweco. For help with the database implementation.

Mario Romero, KTH, Computational Science and Technology. For pointing us in the right direction.

Yifang Ban, KTH Geoinformatics, examiner. For critique and examination of the thesis.

Finally thanks to: Ulf Jensen (VA Syd), Bennie Ekenstierna (VA Syd) and Kertsin Zetterlund (Telge Energi) for taking part in multiple interviews and providing invaluable information regarding the daily routines of utility fieldwork.

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Declaration of Individual Contributions

The individual workload between the authors of this thesis was simplified by the fact that the authors have been working together in several projects before. The division of tasks is based on each of the authors strengths, interests and earlier skills. There have been few days that the authors have been working apart. The majority of the time has been spent at Digpro’s office and that made communication simple. In some parts of the thesis it is difficult to di↵erentiate which part has been done by who since both have worked equally much. The first part is the research done in the first month of the thesis, more particularly all the information gathered for the related work section and work to find suitable frameworks. The second part is the interviews and the implementation of an external server, which was completed with help by sta↵

from Digpro. Both these parts were worked on equally much by both authors.

Oskar has mostly focused on design and implementation of the front-end part of the prototype. He has also created all of the mock-up sketches in Adobe Illustrator.

Most of the interface of the prototype in HTML and CSS and some of the functionality in JavaScript has been done by him. Oskar has also been the one more focused on the augmented reality part of the prototype and the research of how to implement it. Klas has taken care of the back-end work which means the implementation of the database. He has done almost all work regarding OpenLayers and has done general functionality with JavaScript. Klas has also focused on and completed the work regarding the survey.

Regarding the writing of the thesis each author has been slightly more focused on the di↵erent part accounted for in the above description. Klas has focused more on writing than Oskar, mainly because it has come natural to write simultaneously while doing for example design work.

Even though the work has been divided between the authors in di↵erent categories each author has the been a part of what the other one have worked on with continuous feedback during each step. This mean that both the authors can describe and present all of the tasks completed in the thesis.

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List of Figures

1 The reality-virtuality continuum . . . 3

2 Shape-understanding versus relative-position tasks experiment . . . . 5

3 Augmented reality platform ARMOR . . . 8

4 2D view on mobile device . . . 10

5 3D view on mobile device . . . 10

6 Method described in a flowchart . . . 11

7 Screenshot of Digpro software product dpWater . . . 16

8 GE FieldSmart standard interface . . . 17

9 Trimble Field Inspector . . . 18

10 Core abstractions of argon.js . . . 21

11 Initial view of prototype . . . 24

12 The prototype with action buttons . . . 24

13 Sidebar menu in prototype . . . 24

14 Layer in prototype . . . 24

15 Mock-up of augmented reality view . . . 25

16 Mock-up of combined view . . . 26

17 Response to 3D visualization can improve fieldwork . . . 27

18 Response to di↵erent cases . . . 27

19 Response to preferred unit . . . 28

20 Response to operation orientation of a tablet . . . 29

21 The alternatives for a zoomed out map . . . 29

22 Response to background map preferred - zoomed out . . . 30

23 The alternatives for a zoomed in map . . . 30

24 Response to background map preferred - zoomed in . . . 31

25 Response to object information preferred . . . 31

26 Response to cross section feature . . . 32

27 Response to inclination feature . . . 32

28 Choice of preferred unit for fieldwork . . . 33

29 Choice of preferred background map when zoomed out . . . 34

30 Choice of preferred background map when zoomed in . . . 34

31 Choice of preferred operating orientation for a tablet . . . 35

32 What information is most important when selecting an object . . . . 35

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Terms and Abbreviations

GIS - Geographic Information System NIS - Network Information System 2D - Two-dimensional

3D - Three-dimensional AR - Augmented Reality VR - Virtual Reality

iOS - Operating system created and developed by Apple Inc.

HTML - HyperText Markup Language JavaScript - Client-side scripting language CSS - Cascade Styling Sheets

GPS - Global Positioning System

GNSS - Global Navigation Satellite System RTK - Real Time Kinematic

IMU - Inertial Measurement Unit

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1 Introduction

New technology generates new opportunities in visualizing data for professionals working in many di↵erent areas. Today, many utility companies, such as those managing water or electricity infrastructure, rely on Geographic Information Systems (GIS) and Network Information Systems (NIS) to be able to manage their underground infrastructure. The established way to use GIS in the field is through paper plans, which are annotated manually on a certain construction site or maintenance site if changes are made and if there is a need to report.

To improve efficiency, notebook computers have replaced paper plans in later years. These are used in the field to directly consult the GIS or NIS. To represent the geographic data, a GIS database normally employs two-dimensional (2D) or three- dimensional (3D) models to represent the data. However, since the physical objects in the utility sector are normally hidden, the development of software using the latest technology with 3D for fieldwork has been limited. Lots of work tasks can be improved by enhancing and simplifying the utilization of the latest visualization technology in new customized applications.

Interactive maps is the most common visualization method for geographical information and is used in our everyday life with varying purposes. Although the supply of applications that uses interactive maps as their foundation has been increasing rapidly, there is still a demand for interactive map applications that uses di↵erent types of visualization methods. The introduction of a more common usage of Aug- mented Reality (AR) and Virtual Reality (VR) technology in mobile applications, opens a new world of possibilities for the development of new applications. One of the areas with a lot of potential for new ideas of new applications is the area of fieldwork. For instance, by including visualization in both 2D and 3D, the user gets a more general overview for localization purposes as well as a first-person view of how objects are located in a 3D space in the surrounding environment.

Digpro is a company that has a lot of experience in providing software for work conducted on utility networks. By providing office space, competence and possible contacts working with fieldwork, Digpro has enabled the possibility in accomplishing the goals of this thesis. Fieldwork is an area that Digpro want to make improved software for and this approach is therefore something that could help to serve as an interesting idea for the future.

1.1 Background

Fieldworkers of today want to access more information as well as be able to use advanced GIS solutions and visualization methods while out in the field. Today most fieldwork is conducted using paper plans or locally stored data on laptops as a visual

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aid. Therefore there is a need for the improvement and development of new reliable visualization software that is easy to use and has good performance.

“A study that consists of practical activities that are done away from your school, college, or place of work”, is the definition of fieldwork by Cambridge Advanced Learner’s Dictionary & Thesaurus (Cambridge University 2017). Since fieldwork is practical work conducted on the move, the usage of mobile applications should be common, but today this is often not the case. In the present, the accessibility of mobile applications on phones and tablets is very high for users in Sweden. However, the development of software adapted for fieldworkers using the latest technology is an area that few people has invested time in. Today most GIS/NIS solutions are designed for people working in an office environment while few are developed for people working in the field. The software that uses GIS/NIS technology is mostly designed for computers and the lightest device where it can be used is a laptop, which is not a suitable device to use in an outside environment. There are however obvious advantages that can be obtained by replacing paper plans and laptops with units more adapted for an outside environment.

In order to be as e↵ective as possible when carrying out di↵erent tasks in the field, di↵erent ways of visualizing the same network data are needed. 2D and 3D visualization methods have di↵erent advantages and disadvantages when it comes to visualizing network data. By determining what these di↵erences are and how one can make the most use of 2D and 3D visualization methods in order to visualize network data, mobile fieldwork applications using these methods can be produced.

The use of Augmented Reality (AR) as a 3D visualization method is rapidly developing in a lot of di↵erent industries with di↵erent purposes. In AR, virtual objects are added to the real environment to enhance reality by presenting additional information that the eye is unable to detect. AR is a part of the reality-virtuality continuum, illustrated in Figure 1, which is the spectrum between the real environment and the complete virtual environment. Location-based AR is one out of a few di↵erent types of AR that takes advantage of smart device’s features to detect location is useful for visualizing geolocated objects (iGreet 2017). AR requires a screen depicting the real world which virtual objects can be added to and is today used on phones and tablets in which the camera can depict the real world. It is for example used for tourist activities to show old or no longer existing buildings at certain spots as well as games for mobile phones (Eisenberg 2017).

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Figure 1: The reality-virtuality continuum. Source: Milgram et al. 1994

1.2 Research Question

This study aims to evaluate how data can be visualized in a simple and user friendly way for a specific type of user. More specifically the study aims to answer the questions:

• How can visualization techniques be used to enhance utility fieldwork in an efficient way with today’s available technology?

• What kind of information does a 2D or a 3D data visualization give the user?

• What hardware and software of today are suitable for visualizing utility networks in the field?

1.3 Objectives

The objectives of this thesis are threefold. Firstly, to evaluate how suitable di↵erent visualization methods are for fieldwork users working with utility networks. Secondly, to get a better understanding of what hardware and software that can be used for the visualization methods for 2D and 3D. Lastly, the results from achieving the first and second objective will be used in order to create a prototype for utility network fieldwork. This prototype will serve as a basis for evaluating the efficiency of using 2D and 3D visualization techniques for visualizing network data for fieldwork users.

1.4 Limitations and Delimitations

The focus of the thesis is to evaluate how visualizing utility networks for fieldwork can be done and therefore also focuses on the fieldworkers as users. The users referred to as fieldworkers in the study are considered as a generalization of people working in the field with utility networks. This kind of work is conducted by people with varying experience of GIS and works in di↵erent scenarios and roles.

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Since this thesis also involves the use of a prototype for evaluating 2D and 3D visualization methods, there are also some technical limitations involved. The work is limited to iOS only since the Argon4 browser only supports iOS at the time being.

Also, the prototype will be developed using HTML, CSS and several JavaScript libraries. Another aspect to consider is that visualized content can be seen di↵erently because of color vision deficiency. Even though this is an important aspect of data visualization, color blindness has not been considered in this thesis.

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2 Related Work

A wide range of information is needed in order to address the objectives of this thesis.

The related work section starts with an overview of how 2D and 3D visualization methods are generally used for visualizing data, this is described in Section 2.1. This is followed by a study of how to visualize pipelines in 3D in Section 2.2. After that the focus shifts to the challenges of implementing AR platforms for fieldwork in Sections 2.3 and 2.4. The chapter ends with the presentation of an utility viewer pilot project using mobile phones for fieldwork in Section 2.5.

2.1 Visualizing 2D and 3D Data

John et al. 2000 study how and when to use 3D visualization on flat screens in comparison on how and when to visualize in 2D. The study is performed by carrying out experiments where di↵erent tasks involving shape understanding and relative positioning are executed. Figure 2 depicts an image used for the first two experiments.

In both experiments the participants were given 10 images in 2D as well as 10 images in 3D. In the first experiment they were to decide which object that corresponds to which image. In the second experiment the participants were to decide which cube that a sphere was hovering directly above.

Figure 2: Material used during the first and second experiment where the top half of the image is the data given separately to the participants in the first experiment to decide which object it corresponds to. The objects are located in the bottom half of the image. In the top right there is an example of the second experiment with the sphere above the cubes. Source: John et al. 2000

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The results show that 3D visualization on flat screens are more useful for tasks such as understanding the shape of 3D objects and to comprehend the layout of di↵erent scenes. 2D has less distortion and excels when it comes to show precise distances and angles between objects. 3D visualization excels at presenting shapes since it can show all three dimensions in one view. It also has the ability to add supplementary depth cues as natural shadows, shading, object scaling and texture gradients. It is however not suitable for perception of an objects’ relative position because of distortions and projective ambiguities. Instead, 2D visualization excels at this by accurately representing an object with ambiguity confined to one dimension (John et al. 2000).

Tory 2004 studies and compares how displays using either 2D, 3D or combined 2D/3D visualization methods can can visualize 3D spatial data. The conclusion is that both 2D and 3D views have their own set of strengths and weaknesses just like John et al. 2000. discovered. A few di↵erences of 2D data and 3D is firstly, the possibility to present depth. Where 2D presents no or little depth cues while in 3D it is presented more natural with more many depth cues. Secondly, to study an image in 2D, it is more difficult to interpret symbols compared to 3D. Thirdly, a 2D visualization covers only a cut out part of a 3D space while 3D visualization covers the 3D space as a whole and it’s structure. A combination of 2D and 3D visualization is proposed as both methods can benefit from each other if their strengths are relevant for the task (Tory 2004).

The conclusions from the above-mentioned studies are highly applicable when building a prototype that includes 2D and 3D data to be visualized in an efficient way. Firstly, to choose dimension of data according to what is to be visualized.

Secondly, to combine visualizations with di↵erent dimensions if possible.

2.2 3D Visualization of Pipelines

There are several challenges when implementing functional visualization methods for fieldwork. Data of underground pipelines and cables are usually modeled in 2D with no or inaccurate information about the height level of the networks and the height di↵erence between pipes and cables underground. In “An Approach for 3D Visual- ization of Pipelines”, Du and Zlatanova 2010 discuss the challenges and problems with visualizing utility networks consisting of pipelines and cables. The study also presents a prototype for 3D visualization of utility networks which involves transformation of line segments for pipelines and cables to tiny cylinders in order to solve the problem that lines are difficult to visualize in 3D. The conclusions from the study show that the determination of z-coordinates for pipelines is essential in order to create the vertical segments that make up the model networks in 3D. Furthermore, the study also shows that 3D visualization of pipelines is much more appealing than 2D visualization when looking at the relationships between pipes and other objects. By

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including 3D symbols in order to show pipeline attachments, additional information is provided about function, direction of flow, connectivity etc. In future work it is suggested that specific functions for pipelines should be developed such as analysis of section, profiles and intersections, as well as analysis of probably malfunctioning pipes and connections. Also additional program developments for refining the 3D visualization are desirable (Du and Zlatanova 2010).

The theories presented in the article may not be directly applicable to the present study. However, it can be used to show how to visualize 3D pipelines and therefore act as additional support to why 3D visualizations are appealing when looking at the relationship between pipes and other objects in the near vicinity.

2.3 Civil Infrastructure System Applications

Behzadan, Dong, and Kamat 2015 reviews critical problems and investigates technical approaches in AR to address the fundamental challenges that prevent technology from being further used in civil infrastructure system applications. Two key challenges are associated with AR. The first regards spatial alignment of entities, a.k.a. registration.

The second is visual illusion of real world and virtual coexistence, a.k.a. occlusion.

How these challenges are managed is key for using AR.

The requirement to blend physical and synthetic objects distinguishes AR from other visualization technologies. The uniqueness is threefold. Firstly, it strengthens the connection between users and objects. Secondly, it allows the user to perform fieldwork with an awareness of both the physical and synthetic environment and finally it reduces the cost of 3D model engineering by including the real world background.

There are multiple examples of how research has been successfully deployed with large economic and social impact. One example includes an AR visual excavator- utility collision avoidance system that enables users to visualize buried utilities hidden under the ground surface which reduces the risk of accidental utility breakdowns.

Another example is an AR post-disaster framework that enables inspectors to evaluate the amount of damage done to structures and buildings in seismic events such as blasts or earthquakes.

A big advantage of using AR instead of VR is that AR preserves the user’s awareness of the real environment by visualizing both the real world and the virtual objects in a mixed 3D space. This provides users with hints to discover their surrounding environments and help them perform real-world tasks.

An example of an AR application includes a helmet with attached sensors and a backpack with additional hardware, see Figure 3. The hardware platform is named ARMOR, acronym for Augmented Reality Mobile Operation platform, and has a Global Position System (GPS) antenna, an electronic compass, a Head-Mounted Dis- play (HMD) and a camera attached to the helmet. The backpack carries a laptop, a

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Real Time Kinematic (RTK) rover radio antenna, a RTK rover radio, a RTK rover receiver and a power source for the HMD. The choice of hardware and software is motivated by three specific needs which are also considered prohibiting factors for AR applications in civil infrastructure These factors are: mobility, extensibility and scalability.

Figure 3: The AR platform ARMOR, acronym Augmented Reality Mobile Operation platform,from di↵erent perspectives. Source: Behzadan, Dong, and Kamat 2015 Further the article covers the challenges of underground utilities where water and waste water pipelines share the underground space together with gas pipes, communication lines, rail and road tunnels. Because of continuously growing underground infrastructure, it gets more and more difficult to know or visualize what lies buried in the vicinity that make utilities struck and damaged (Behzadan, Dong, and Kamat 2015).

The theories of this study is highly relevant when visualizing 3D data using AR and acts as support to why AR is relevant in the field of civil infrastructure and in utility fieldwork. The proposed fieldwork solution that the study supplies, serves as a solid base to understand the necessary features needed for implementation for a fieldwork application.

2.4 VIDENTE

In the VIDENTE approach a handheld AR system of on-site visualization and interac- tion is used, which is an approach also described in an article by Scahll, Schmalstieg,

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and Junghanns 2010 called “VIDENTE - 3D Visualization of Underground Infras- tructure using Handheld Augmented Reality”. The article covers the AR system VIDENTE, its potential fields of application and the benefits of the system. The system is described as having the potential of supporting mobile workforces in the complete life cycle of water infrastructure, thus revolutionizing traditional planning, operation, maintenance, on-site inspection, fault management and decision-making methodologies. Also, tasks concerning maintenance and operation in fieldwork are efficiently accomplished while improving general safety and reducing unintended damage on site. The article states:

“AR has the potential to remove the need for a mental transformation from map to reality. As the supply and utility grids get smarter, the need for smarter mobile systems grows. Mobile field information systems for supporting the mobile workforce in on-site tasks are increasingly vital.”

Three-dimensional representation and visualization of urban environments are em- ployed in an increasing number of applications, like urban planning and emergency tasks. A procedure to make use of large productive geospatial databases is called transcoding: a process of turning raw geospatial data, which are mostly 2D, into 3D models suitable for standard rendering engines (Scahll, Schmalstieg, and Junghanns 2010).

Scahll, Schmalstieg, and Junghanns 2010 pinpoint the need and applicability of AR in the area of utility networks and support the fact that the workflow of utility fieldwork is in need of technical development which acts as support for the theories in the thesis.

2.5 GeoSmartCity

GeoSmartCity 2017 o↵ers a platform for sharing and publication of geographical data. In one pilot project called the South Moravian Region by Intergraph CZ a mobile application is developed for public administration and utility companies. The application consists of two branches, one being a crowd sourcing application and the other a utility viewer application. The purpose of the second branch is to enable utility companies to visualize underground utility infrastructure on mobile devices with support from AR. The major functionality of the application consists of viewing infrastructure in a 2D map, see Figure 4, and a 3D AR view, see Figure 5. It also enables the user to get information from infrastructure objects and to use an external Global Navigation Satellite System (GNSS) device. The external GNSS-device uses Bluetooth to connect to the mobile unit and gets high precision positioning for the device (GeoSmartCity 2017).

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The second branch is not a finished product and is more a proof of concept regarding utility visualization. However, the application is applicable to the thesis as proof that location-based AR is possible when visualizing utility network and as a basis considering fieldwork applications.

Figure 4: 2D view on mobile phone showing 2D data. Source:

GeoSmartCity 2017

Figure 5: 3D-view one mobile phone showing 3D utility data in AR. Source:

GeoSmartCity 2017

3 Research Methodology

The objective of this thesis is to evaluate di↵erent visualization methods for field work on utility networks, as well as developing a prototype. A water/sewer utility network is used as test data used in the prototype. This section covers the main steps of the workflow for the thesis, see Figure 6 for the methodology described in a flowchart. The first part is about understanding the needs of the fieldworkers when performing their most important work tasks. This is mainly accomplished by conducting interviews and by studying related literature. Further, the di↵erent criteria for the visualization of utility network data is presented and the process of sketching mock-ups and developing a prototype is accounted for. Finally, the process of evaluating the prototype and the implemented visualization methods are explained.

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Interviews Feedback

Mock-up Study

related work

Back-end development

Evaluate prototype Implement

prototype

Front-end development

Quantitative feedback

Draw conclusions Qualitative

feedback

Figure 6: Method described in a flowchart.

3.1 Cases

The cases in focus when developing the fieldwork prototype are the three most common types of cases there are when working hands-on with utility networks. These three cases are:

• Emergency cases: This is usually a leak somewhere in the network that quickly has to be repaired in order for people to get a normal working and functional service. This can in some cases mean a matter of life and death depending on who and what services that are depending on a certain part of the damaged network as well as what kind of network that is out of order.

• Maintenance: The most common case is the on-going maintenance work on the utility networks in order to keep networks functional and avoid emergent breakdowns. The networks are inspected periodically and old and malfunctioning components can be found and changed before they cause any possible threat of an emergency. This work is usually based on filling in an inspection form of the controlled components in order to update the components status.

• Larger planned projects: Despite maintenance, parts of the network sometimes has to be reconstructed and this is usually something that has been planned for some time. Another type of planned projects is extension of the network.

3.2 The Users

As mentioned, the user group this thesis focus upon is fieldworkers working with utility networks. Their tasks can involve inspection, maintenance and also construction of new pipelines with associated components and couplings. The fieldworkers work mostly outside and are in need of software that is adapted for their work and is able to aid them in performing their tasks on the move. The most important tasks for

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fieldworkers working with inspection is basically localization of utilities and being able to fill in protocols. In more urgent cases, the possibility to change the status of the a↵ected components and to quickly get people with the right competence to the spot, is critical. The prototype created in this study is designed to aid fieldworkers in their work when encountering all these di↵erent scenarios.

3.2.1 Interviews with Potential End Users

To understand the everyday work of fieldworkers that work with water and sewer networks, a few people working at two di↵erent companies in two di↵erent cities in Sweden are interviewed. The focus of the interviews is to find out how visualization of the utility networks are used today, what the major issues are and how the workflow for a fieldworker looks like. The purpose of the interviews is also to understand how maps and GIS are used in fieldwork today in order to make decisions based on proper information and localize the main areas of interest. The interviews are conducted by talking to engineers that have an overall responsibility of how the maintenance of water systems is performed. The contacts are provided by and are customers to Digpro. The engineers work partly out in field but most fieldwork is performed by other employees. Since the interviewees have detailed knowledge about the workflow in the field, there was no immediate necessity for interviews with people that work in the field on a more daily basis.

The questions asked in the interviews focus on the users and their workflow and how they use maps for support when working in the field. Some examples of questions asked are:

• Can you describe your professional role - what is your role in the organization and what are your main responsibilities?

• Description of the workflow - how is the work for di↵erent networks most often conducted? (Both planned and emergency work)

• How do you use maps in order to make decisions?

• What are the biggest challenges in your work?

• What additional information would you like to have in the fieldwork that currently is not available in a simple way today?

An interesting and important aspect to take into consideration when analyzing the results is the current software or map that is used for localization and visualization by the fieldworkers. Also what software or work method that has been used in the past.

The interviewee tends to compare their experience working with the newer technique

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compared to the older one when trying to describe pros and cons with their current technique. This did not influence the outcome of the development of the prototype, but was taken into consideration. It is favorable that the functions that currently works fine, works even better in the prototype and really highlight these features if it comes to presenting the prototype for the users. This is a way of getting the users to get something else to compare the efficiency of a certain feature instead of just compare to their old techniques.

3.3 Hardware and Software Criteria

Based on the interviews, literature and the authors’ own knowledge, criteria for hardware and software are determined in order to find the best solution for implementing a visualization of utility networks for fieldworkers. In the section below, criteria for both hardware and software are accounted for.

3.3.1 Hardware Criteria

There are multiple criteria for the hardware of the prototype which is based on the need of mobility and communication. The hardware device should:

• Be mobile and easy to carry

• Be robust and weatherproof

• Be able to visualize 2D and 3D

• Have a GPS receiver and an Inertial Measurement Unit (IMU)

• Have mobile communication

As fieldwork is conducted on the move the unit need to be mobile, fairly easy to carry, be robust and weatherproof. Most hardware units that were considered have di↵erent types of additional screen covers or other protective gear for additional pro- tection. The hardware unit need to have the possibility to visualize data in both 2D and 3D. Especially 3D visualization is demanding and needs a device with a fairly powerful processor to enable smooth 3D visualization. For positioning and orientation of the device it should have a GPS receiver and an IMU with an accelerometer, gyroscope and a magnetometer. Finally, the device should also be able to use mobile communication to receive information while out in the field.

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3.3.2 Software Criteria

When choosing suitable software for visualizing utility network data for fieldwork, a few important aspects are to be considered. The following criteria is decided for the prototype, the software should:

• Be open source

• Be able to visualize 2D and 3D

• Use an external server

• Have a database

Overall, the software used for producing a prototype should be open source. This is because it entails security, quality and customizability with all code being available and with a waste amount of people contributing. Further, the prototype should be able to visualize data in both 2D and 3D. Another criterion is the possibility to have an external server so the application can be accessed from anywhere. Lastly the prototype needs to have a database to store all the necessary data, especially network data.

3.4 Currently Used Technology Review

This section covers potential technology that can be used, or is being used for fieldwork today. The section is divided into reviews of hardware devices, their advantages and disadvantages as well as software used for fieldwork today.

3.4.1 Hardware

This section presents di↵erent hardware devices that can be used as basis for a fieldwork application. Their di↵erent characteristics are compared in relation to the criteria presented in Section 3.3.1.

3.4.1.1 Laptops

A laptop is suitable for processing large amounts of information and can be used to visualize data in both 2D and 3D. However, in most cases, it can not be used to visualize AR, since the camera of a laptop usually is located on the front side of the screen which is faced towards yourself. This could be solved by using an additional camera for that purpose. Laptops usually have less computational power than a desktop computer but most software a fieldworker needs works fine on a laptop. The mobility is said to be one of the biggest advantages of a laptop, though in later years,

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this advantage has been challenged by smaller units like tablets and mobile phones.

Laptops are perfect to use in comfortable environments like an office or a train, but has problems when it comes to functionality in more exposed conditions. Laptops today usually have an integrated GPS receiver, if not, there are a lot of additional receivers to get for a laptop with varying performance. A laptop can also be used for mobile communication if it can receive an internet connection.

3.4.1.2 Phones and Tablets

Mobile phones and tablets are smaller devices than laptops and are made to be more mobile in comparison to laptops. However, the computational power is significantly less compared to the power of a laptop. The main di↵erence between phones and tablets is the screen size, which of course can vary between di↵erent brands and editions. Most phones and tablets are equipped with sensors that satisfies the same needs. They also have an IMU and a GPS for determination of the position and orientation. Since the screen size vary it suits di↵erent users and objectives. Most phones and tablets have a front and a rear camera which is an advantage when it comes to modelling 3D by AR (phoneArena 2014).

The di↵erence in computational power between laptop and a phone or tablet is reflected by the di↵erence in size of the unit. This di↵erence is also an aspect between tablets and phones, where tablets usually also has larger computational power than phones. This means that tablets can manage larger amounts of data and handle more demanding processes. However, a problem that phones and tablets share is the performance of the integrated GPS receiver. The receiver usually has low accuracy which can be a problem when working with utility networks out in the field.

3.4.1.3 Goggles and Smart Glasses

Goggles, or smart glasses, is an alternative which di↵er a lot from the other types of hardware devices that is addressed in previous sections. There are a few di↵erent types of goggles out on the market today and they share several key characteristics.

Goggles are attached to your head and are operated by either gestures or voice com- mands. This makes goggles suitable for work that includes movement and in di↵erent environments as well as for mobile communication. However, goggles that are available for purchase today are also sensitive for di↵erent conditions such as rain. Today goggles do not include a GPS receiver in most cases, which can be problematic when trying to visualize and locate spatial data in the field. Another disadvantage with goggles is that they are not adapted for people that has issues with their eyes and maybe already uses glasses for that purpose. There are however possibilities to visualize data in both 2D and 3D. AR is common usage for goggles since goggles covers

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the eyes of the user which makes it suitable to project virtual objects on the screen in front of the eyes. The possibility to process larger amounts of data depends on external computer power for goggles, which can be problematic (Schweizer 2014).

An example of goggles that is available for purchase is HoloLens. HoloLens is a pair of smart glasses that is developed and manufactured by Microsoft and can visualize 3D. The glasses have an IMU, four sensors for understanding of the surroundings, a depth camera, photographic video camera, a microphone array and an ambient light sensor (Microsoft 2017).

3.4.2 Software

In this section, multiple software products are looked into in order to highlight what software are available for fieldwork on the market today. The products’ main func- tionally and how that relates to fieldwork is briefly covered.

3.4.2.1 Digpro Products

Digpro develops software clients available for di↵erent utilities. One example is dp- Water, see Figure 7, which is a web-based NIS for desktop computers and laptops which uses maps to manage water utility networks (Digpro Solutions AB 2017). dp- Water allows the user to plan, build, deploy and maintain networks and can be used for fieldwork.

Figure 7: Screenshot of Digpro software product dpWater.

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3.4.2.2 GE FieldSmart Products

MapFrame^TM FieldSmart is the name of several applications developed by General Electrics (GE) for any Windows supported device, see Figure 8. The applications o↵ers fieldwork users the ability to view not only GIS data, but also AutoCad data, raster data and aerial imagery. GE claims to reduce data entry by 50-80% and paper consumption up to 70% by using FieldSmart. The products are focused on inspection, management and design and the main purpose of the applications is to make field work processes more cost e↵ective with easy-to-use tools to service and maintain network assets (General Electric Company 2013).

Figure 8: The standard interface of GE Fieldsmart. Source: General Electric Com- pany 2013

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3.4.2.3 Trimble Field Inspector

Trimble has developed a software product called Trimble Field Inspector which runs on Trimble handheld devices and Android smartphones. The product works by com- bining desktop functionality with fieldwork by sending jobs and designing forms on the desktop which are then sent to the handheld device or smartphone when performing maintenance and inspection tasks out in the field (Trimble 2017). The product allows the user to view assets on Google Maps and gives the user the necessary information and possibility to fill out inspection forms on a handheld device or smartphone instead of using paper forms. The product also includes positioning functionality as well as functions for photos, sketches and barcode scanning.

Figure 9: Trimble Field Inspector shown on a Samsung phone. Source: Trimble 2017

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3.5 Mock-ups

Before the work on a prototype can start, a few mock-up sketches are made in order to present how the prototype should look and function. Mock-ups are sketches that are drawn to present how the prototype will look before anything is actually implemented, whereas a prototype is the actual implemented and functional pre-version of an application. The mock-ups includes three di↵erent views. First a 2D map view, secondly a 3D view to visualize the data with AR and finally a combined 2D and 3D view to show how the 2D respectively the 3D visualization supports each other as explained in Section 2.1.

The hardware device chosen for the mock-up sketches is a tablet. It is favorable to chose a device to use as an example since performing sketches for several devices is a time consuming task. The choice is based upon the review of di↵erent hardware units in Section 3.4.1 as well as information gathered from the interviews with potential users in Section 3.2.1 and the related work in Section 2. A tablet has much in common with a mobile phone when it comes to performance, but the fact that a tablet is a larger unit and has higher computational power makes it the top choice.

The interface of the mock-ups are inspired by OpenStreetMap, Digpro’s software dpWebmap and functionality from Google Maps. Other Digpro products like dpWa- ter inspired the design of forms and menu choices. The design was derived from these inspirational sources in order to feel familiar and be functional for users not experi- enced with other GIS software. The design is adapted for performing work tasks in an outside environment by making fewer di↵erent and specific buttons with larger icons that can easily be reached and interacted with in the field. The mock-ups are drawn in Adobe Illustrator and they can be found in Appendix 1. The first version of the mock-ups were presented to employees at Digpro as well as the potential potential users interviewed in Section 3.2.1. This provided useful feedback which is the basis for evaluating and modifying the mock-ups. The modified mock-ups are the basis for how the prototype should look when the features are implemented.

3.6 Prototype

The prototype is developed based on the mock-ups and the feedback received from presenting the mock-ups. One of the most critical tasks when developing a prototype is to find frameworks that can be implemented for programming a prototype. It is necessary that these frameworks meet the requirements of fieldwork, especially when it comes to the criterion that the application can be used on the move. It is also important that the used frameworks is open source, since it is easier to control and adapt the code to satisfy the needs of the prototype. Another aspect is for the prototype to cover for the di↵erent cases presented in Section 3.1. The prototype

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is built in order to cover for the requirements of the di↵erent cases as equally as possible. Emergency cases requires e.g. good mobile connection and the possibility to get data from external sources. Maintenance and larger planned projects requires the ability to store larger assignments with the possibility of direct-manipulation of data. Additionally these cases requires the possibility to fill in inspection forms with design adapted for di↵erent objects.

3.6.1 Implementation

The prototype functions as a web application with an interactive 2D map serving as the default interface. There are also possibilities for the user to switch to view their surroundings in 3D by with AR functionality. The 2D and 3D views are possible to view in a combined mode where half on the screen shows the 2D map and the other shows the AR view. The full source code of the prototype is available at:

https://github.com/Klabbeee/OskKla2017.

3.6.1.1 Frameworks

HyperText Markup Language (HTML) is the standard language when making web applications and web pages and is supported by all major browsers which strengthens its position in web development. HTML5 is the latest version of HTML and adds two di↵erent concepts. Compared to earlier versions, HTML5 comes with new ele- ments, attributes and behaviors and allows powerful and more diverse web sites and applications. Technologies generally used in unison with HTML to describe a web pages presentation or functionality are Cascading Style Sheets (CSS) and JavaScript (Mozilla1 2017).

CSS is the language mainly used for describing the presentation of a document that is written in a markup language like HTML. The main function of CSS is to separate the document content from the document presentation which includes aspects like choosing colors, fonts and layouts (Mozilla2 2017).

JavaScript is a scripting language commonly used to add functionality to web applications. JavaScript is object-based and supports declarative and imperative programming styles, which makes it a powerful tool in developing web applications of all di↵erent kinds (Mozilla3 2017). JavaScript has a large amount of libraries based on the language which makes it easier to implement more sophisticated functions since you do not have to build them from scratch. A few libraries are key in this thesis, particularly OpenLayers, argon.js, three.js and Cesium.js.

OpenLayers is a JavaScript library that makes the creation of dynamic maps in any web application easy and can serve as the foundation for interactive 2D maps.

OpenLayers can help display vector data, map tiles and use a wide range of markers.

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The latest version is OpenLayers4, which is also the version used for the development of the prototype. The OpenLayers API functionality makes it possible to get information about the users position, the accuracy of the position and has the possibility to show that on a map (OpenLayers 2017).

argon.js is a framework which with is associated with the Argon web browser. Ar- gon4 uses web technologies to create 3D AR applications that can deliver 3D graphics and geo-spatial-positioning. The main task for argon.js is to supply an abstraction layer for AR between the web-application and the Argon4 browser. The Argon4 browser is currently only available on iOS but will be available on android in the future. argon.js is defined by three core abstractions; a reality augmentor, a reality view and a reality manager, see Figure 10 (Georgia Tech Research Corporation 2017).

Figure 10: The three core abstractions of argon.js. The reality augmentor augments a view of the reality, the reality view presents a view of the reality and the reality manager blends a particular reality view with one or more reality augmentor. Source:

(Georgia Tech Research Corporation 2017)

Both three.js and Cesium.js are integrated into the argon.js framework to visualize geocoded AR. three.js is a library for rendering 3D content and is used since argon.js does not prescribe any rendering. When content is rendered in three.js it is placed in three.js internal coordinate system. Therefore Cesium.js, a library to create and build 3D globes and maps, is incorporated to transform the rendered content to a global coordinate system (Georgia Tech Research Corporation 2017).

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3.6.1.2 Front-End Development

The goal of front-end development of a prototype is to get the user to understand the concepts of an interface. It is important that the tools and features look familiar and are easy to grasp for the intended users. It is also important that the user easily can navigate between di↵erent functions that can be either hidden and more visible in the interface.

The prototype is built as a web application where one goal is for it to function for any browser, but since AR is being used, the prototype only functions in the Argon4 browser on iOS. The first step of the front-end development is to build the interface which is based on the mock-ups. The interface is created using primarily HTML, CSS and JavaScript. When the visual appearance of the interface and the basic functionality is deemed as acceptable, further functionality is implemented. The 2D map functionality is built using the JavaScript library OpenLayers4. Simultaneously the basic 3D view with AR is built using the three Javascript libraries argon.js, three.js and Cesium.js. When the basic functionality of both views have been created, the combined view is implemented followed by more functionality.

3.6.1.3 Back-End Development

To complement the front-end interface, the prototype need to have a back-end com- ponent as well. To efficiently store network data, a PostGIS spatial database is used. The database is based on the database built by Hilding and Syk 2016. In this database, geographic data, such as information about customers and the network is stored. Much of this data are relevant to show as example data in the prototype.

The database has a simple structure and can not be compared in complexity with databases used to store larger amounts of NIS data. However it uses the relationships between nodes, arcs and customers that a NIS should be expected to have. By using a server written in Python which uses a framework called Flask, the web-client can communicate with the database. Flask is called a micro-framework, this means that Flask aims to keep the core simple but extensible (Ronacher 2017).

3.7 Feedback and Evaluation

To strengthen that the prototype meets the requirements and criteria, the last step is to obtain feedback and evaluate the prototype. The feedback is received in both a qualitative and a quantitative manner.

The qualitative feedback is received when the prototype is presented to a few expert users working both with GIS software for example Digpro’s products and in fieldwork. During these presentations, all functionality in the prototype is demon- strated and the purpose of each function is explained. Questions are also asked in

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order to get directed feedback for certain key features. This process is repeated during the project for both the mock-ups and the prototype. The questions asked are similar to the questions asked in the quantitative feedback approach. The major dif- ference between the approaches is that during the presentations, listeners receives a live demonstration of the prototype and has the possibility to give direct feedback anytime and discuss features and the process as a whole.

A web survey and a smaller survey during a presentation for potential end users is performed in order to get quantitative feedback. The group receiving the survey questions is a group consisting of both people working with Digpro’s products and people working with fieldwork in the area of utility networks. These group can have di↵erent experience in working with GIS applications, from a more novice level to expert users. The questions asked are focused on visualization of utility network data in 3D since this is a feature not existing in most of the software today. They are also asked to choose between di↵erent background maps and what hardware they think is the most suitable for fieldwork, to mention a few examples.

4 Result and Analysis

In this section, the results will be presented by showing images of the latest version of the prototype as well as the results from the survey followed by an analysis of the survey. Not all images of the prototype are presented here and the rest can be found in Appendix 2. Since the prototype was not fully finished some mock-ups are also presented in Appendix 2 to show how the prototype is supposed to look. A few selected questions will be presented in Section 4.2 and the full survey can be found in Appendix 3.

4.1 Prototype

The start screen of the 2D view of the prototype is shown in Figure 11 and shows the city center of Stockholm, capital of Sweden, using the terrain basemap from Stamen 2017. In Figure 12 the action buttons are displayed showing the two buttons to zoom to user position or to layer and the three buttons to switch view between the 2D, 3D and the combined view. The sidebar menu containing user information, mission information and layers is shown in Figure 13. In Figure 14 a utility layer is shown.

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Figure 11: The initial 2D view of the prototype on a tablet.

Figure 12: The prototype with action buttons. The action buttons are, from the top: Zoom to layer, zoom to user position, combined view, AR view and 2D view.

Figure 13: Sidebar menu in prototype showing user information, mission information and layers menu.

Figure 14: One layer showing utility data in the prototype.

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The 3D AR mock-up view is shown in Figure 15 and shows four layers, three for pipes and one for points of interest and in Figure 16 the mock-up of the combined view is presented showing the same data in 3D and 2D in two separate views next to each other. In Figure 16, an object is selected in one of the views and the corresponding object in the other view is also highlighted. The object in the 2D view is small but is in the center of the 2D view where the pipe layers cross each other.

Figure 15: Mock-up of the 3D augmented reality view showing four layers, three pipe layers and one with points of interests.

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Figure 16: Mock-up of combined view showing the same layer in both views.

4.2 Survey and Presentation

Results of several questions asked in a survey and during a presentation of the thesis for potential end-users is accounted for in this section. The participants that is asked questions have varying background and knowledge regarding GIS software and fieldwork. What they have in common is that all of them is somehow working with utility networks.

4.2.1 Survey Results

This section presents the first part of the quantitative feedback which is a survey that is sent by email to a varying set of companies working with fieldwork and with GIS software. The feedback comes in form of partly multiple-choice questions as well as questions where the participants are able to write a shorter answers. Nine people from eight di↵erent companies have participated in the survey.

4.2.1.1 Cases and Visualizing Fieldwork

The first questions of the survey is about if the users think that the approach of visualizing utility networks in 3D is something that they think can improve fieldwork.

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Also what cases the participating users’ companies are working with.

Figure 17: Response to 3D visualization can improve fieldwork.

As seen in Figure 17, almost all of the participants thinks fieldwork can be improved by visualizing utility networks in 3D. The users are also able to answer when and how this could be useful. One opinion that several of the users shares is that it would be useful to show the relationship between the di↵erent pipelines and cables below ground.

Figure 18: Response to di↵erent cases.

The second question is about which cases of fieldwork that the participants’ company work with. Almost everyone of the participants answer all of the di↵erent cases, see Figure 18, since it is possible to chose multiple answers. The question is designed to give a hint of how common di↵erent cases are. A minority of the participants

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answer none of the above. These participants do not work directly with fieldwork at their companies. To be able to cover for cases not treated by the thesis, a follow up question if the participant work with another, not yet covered fieldwork case, is answered. Examples of answers on this question was e.g. analysis of the existing utility network and surveying to determine terrestrial points.

4.2.1.2 Hardware Unit

This section covers which hardware unit the participants think is most suitable for fieldwork and how they prefer working with a tablet, as covered by Figure 19.

Figure 19: Response to preferred unit.

A majority of the participants prefer working with a tablet. Goggles is the second most popular choice. Laptop also has a minority of the votes and mobile phone do not have any votes.

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Figure 20: Response to operation orientation of a tablet.

Almost everyone answering the survey prefer working with a tablet in a landscape position instead of a portrait position as seen in Figure 20.

4.2.1.3 Background Map

In this section, questions about di↵erent background maps are answered. In the questions, the first four maps in Figure 21 and Figure 23 are addressed respectively.

(a) Google Maps. (b) Stamen Maps, Terrain.

(c) Mapbox, Light. (d) Mapbox, Dark.

Figure 21: The alternatives for a zoomed out map.

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Figure 22: Response to background map preferred - zoomed out.

(a) Google Maps. (b) Stamen Maps, Terrain.

(c) Mapbox, Light. (d) Mapbox, Dark.

Figure 23: The alternatives for a zoomed in map.

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Figure 24: Response to background map preferred - zoomed in.

In both questions, presented by Figure 22 and Figure 24, the first alternative, representing a map from Google Maps has received the majority of the votes. The second alternative, a terrain background map from Stamen, was the second most preferred choice. Only two choices are displayed in the legend because the other two options were not chosen.

4.2.1.4 Object Information and Possible Features

This section covers results for questions about object information and possible features that can be added to the prototype. The first question asks the participants to chose what object information they think is the most important when selecting an object.

The second and third question asks if the participant believes that there is an interest in visualizing cross sections and inclination in 3D for utility networks.

Figure 25: Response to object information preferred.

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A majority of the participants answers that object ID is the most important information, as presented by Figure 25. A few participants prefer object name instead.

Figure 26: Response to cross section feature.

Figure 27: Response to inclination feature.

As seen in Figure 26 and Figure 27, a majority of the voters believe that cross sections and inclination would be good features to visualizing pipelines and cables. They are also able to give suggestions of when and how such features will be used. Examples of suggestions for potential use of the features were during excavation work and when performing plausibility assessments.

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4.2.2 Presentation Results

In this section, the results from questions asked at a presentation for users working with Digpro software are presented. The total number of voters on the presentation that are accounted for is 23, where the majority of the participants also work with fieldwork in the area of utility networks. Everyone did not vote for every question which results in a lesser number of voters for some questions. Furthermore, all alternatives did not receive votes, which makes the answers have fewer alternatives than the actual question. The questions are the same as some of the questions conducted in the survey. However, due to the time limit for the presentation, a few questions from the survey was not included during the presentation. The questions were asked before the actual implementation was presented, in order to avoid biased answers as much as possible.

4.2.2.1 Choice of Hardware

Which hardware unit that is preferred by the voters for fieldwork is presented in Figure 28. The choices the audience could choose between are a tablet, a mobile phone, a pair of goggles and a laptop.

Figure 28: Choice of preferred unit for fieldwork.

A small majority of the audience voted for goggles, 52.4% and the rest voted for a tablet, 47.6%. The other choices, phones and laptops, were not chosen by anyone in the audience.

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4.2.2.2 Background Maps

The choices for background maps presented for the audience is the same as presented by Figure 21 and Figure 23.

Figure 29: Choice of preferred background map when zoomed out.

Figure 30: Choice of preferred background map when zoomed in.

The majority of the voters prefer background map (a) from Google Maps in both zoomed in and zoomed out context. 65.2% for the zoomed out background maps respectively 76.2% for the zoomed in background maps. The answer for the second background map and the third background map was equal for the zoomed out version of the background maps, 17.4%. For the zoomed in version, the second choice had a small increase to 19% in popularity meanwhile the third choice decreased to 4.8%

compared to the zoomed out version. The fourth choice did not receive any votes by the audience.

4.2.2.3 Tablet Operating Orientation

This question is the same as in Figure 20 and presented to the audience.

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Figure 31: Choice of preferred operating orientation for a tablet.

The majority, 69.6%, voted for a laying position for a tablet as choice for work compared to a standing position.

4.2.2.4 Object Information

The question about what object information that is the most important when selecting an object during fieldwork was asked to the audience. The question asked is the same as the one presented in Section 4.2.1.4.

Figure 32: Choice of what information is most important when selecting an object.

A majority, half of the audience considered object ID as the most important object when marking an object. 27.3% preferred object name and 22.7% preferred another attribute than those given for choice.

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4.3 Quantitative Analysis

The participants in the survey as well as participants from the presentation are both groups consisting of a similar group of people. The participants are people working at companies working with GIS software and people working with fieldwork. Some of the participants works in offices while some work directly out in the field. What they all have in common is that they are working in the area of utility networks. The participants have di↵erent knowledge of how the actual prototype is implemented and what choices that already had been made. Some of the participants know that the choice of hardware unit for the prototype was chosen is a tablet, but the majority had no such information. It is important that most of the audience do not know about the implementations made or the di↵erent scenarios before they answered each question, since knowing beforehand probably would have a↵ected the result.

An interesting result is the participants’ choice of hardware for fieldwork. Goggles seem to be a popular choice, which is probably due to the possibility to have the hands free when conducting fieldwork. This is interesting since it would probably been the number one choice for the prototype as well if there was a suitable way to do programming, integrate with an interface and easy to receive a device available for testing. Furthermore, it is not possible to fill in forms using goggles. This is further discussed in Section 5.2.

The participants did not receive any information about the background maps besides that they were in zoomed in respectively zoomed out views. The preferred choice was obviously the first choice for both questions. This is interesting since the background map used in this choice is the background map from Googles Maps. Since the majority of the participants has been using Google Maps before, this could have influenced the participants. Another aspect can be that this map is the only one that has objects such as restaurants included in the map, churches and other points of interest.

Another interesting result is the choice of the most important information when marking an object. The most important information for a selected object in the prototype based on feedback during the process of the mock-ups, would have been the object name. Since such a large majority voted for object ID as the most important object information, this should be considered for further development of an application.

4.4 Qualitative Analysis

The qualitative part of the feedback is received during presentations of the prototype and mock-ups during several meetings during the development process and at a later stage when the prototype is being implemented. The participants received demo