Graphical user interface for supporting process automation in ......a traditional process view...

Graphical user interface forsupporting process automation

in underground mines

Filip Lundeholm and David Jakobsson

May 8, 2012Master’s Thesis in Computing Science, 2x30 credits

Supervisor at CS-UmU: Helena LindgrenExaminer: Anders Broberg

Umea UniversityDepartment of Computing Science

SE-901 87 UMEASWEDEN

Abstract

The mining industry has recognized the need for streamlining the production using modernprocess control systems. In this thesis, a graphical user interface has been designed thatgives the mine operator an improved overview of the physical mine, its production andinvolved resources compared to current user interfaces.

A conceptual demonstrator was developed that implements essential features, includinga traditional process view showing production points and ore movement, an enhanced Ganttchart and a geographical mine view using a visualization technique for 3D to 2D mapping.In depth individual research has also been conducted, focusing on Gantt charts adapted forcontinuous mining processes and a design process reflection that discusses the difficultiesfaced by university students in real work environments and suggestions for overcoming them.

Contents

1 Introduction 1

1.1 ABB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

2 Methods 3

2.1 Assessing the User Context and Requirements . . . . . . . . . . . . . . . . . . 3

2.2 Idea generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

2.3 Concept generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

3 Results 5

3.1 Assessing the User Context and Requirements . . . . . . . . . . . . . . . . . . 5

3.2 Visualisation and concepts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

3.2.1 3D mine model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

3.2.2 3D to 2D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

3.2.3 Visualization of movement . . . . . . . . . . . . . . . . . . . . . . . . . 13

3.2.4 Vehicle and resource visualization . . . . . . . . . . . . . . . . . . . . . 13

3.2.5 Visualization of toxic gas . . . . . . . . . . . . . . . . . . . . . . . . . 14

3.3 Work scheduling using Gantt charts . . . . . . . . . . . . . . . . . . . . . . . 16

3.3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

3.3.2 Icons instead of text . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

3.3.3 Visualisation of progress . . . . . . . . . . . . . . . . . . . . . . . . . . 30

3.3.4 Visualisation of delays and schedule collisions . . . . . . . . . . . . . . 33

3.3.5 Activity chain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

3.3.6 Vehicle transportation time . . . . . . . . . . . . . . . . . . . . . . . . 37

3.3.7 Related work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

3.4 The Demonstrator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

3.4.1 Process Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

3.4.2 Process view layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

3.4.3 Ore tracking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

3.4.4 Map view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

3.4.5 Gantt view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

iii

iv CONTENTS

4 Discussion 47

4.1 Reflections on the workprocess . . . . . . . . . . . . . . . . . . . . . . . . . . 47

4.1.1 Human Computer Interaction . . . . . . . . . . . . . . . . . . . . . . . 48

4.1.2 User Centered Design . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

4.1.3 Action Research . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

4.1.4 Reflections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

5 Conclusions 51

6 Acknowledgements 53

References 55

List of Figures

3.1 The the roles as we understood them. The arrows represent the communica-

tion directions between roles. . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

3.2 The Gantt chart software currently used . . . . . . . . . . . . . . . . . . . . . 7

3.3 The physical map hanging on the wall behind the operator . . . . . . . . . . 8

3.4 The map software currently used . . . . . . . . . . . . . . . . . . . . . . . . . 8

3.5 A rendered image of the 3D mine model . . . . . . . . . . . . . . . . . . . . . 9

3.6 Screenshot from Blender showing a wireframe version of the 3D mine model . 10

3.7 Screenshot from ABB’s simulation software showing the imported 3D mine

model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

3.8 2D mine map created by flattening out the 3D model . . . . . . . . . . . . . . 11

3.9 Stacked 2D planes preserving some of the depth information . . . . . . . . . . 12

3.10 3D mine model after applying an automatic 2D graph layout algorithm . . . 13

3.11 Concepts for visualization of vehicle movement in a mine map . . . . . . . . . 14

3.12 Concept for vehicle and resource tracking . . . . . . . . . . . . . . . . . . . . 15

3.13 Gas concentration visualized as a point cloud . . . . . . . . . . . . . . . . . . 15

3.14 Bar chart visualization of gas concentrations . . . . . . . . . . . . . . . . . . . 15

3.15 A typical Gantt chart. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

3.16 One of the very first Gantt charts produced by Henry Gantt. . . . . . . . . . 17

3.17 Typical Gantt chart with progressbars. . . . . . . . . . . . . . . . . . . . . . . 18

3.18 Microsoft Project has an advanced implementation of the Gantt chart with

many extensions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

3.19 Reproduction of the Gantt chart used in the studied mine. . . . . . . . . . . . 19

3.20 Colors used in Gantt chart in the studied mine. . . . . . . . . . . . . . . . . . 20

3.21 Simulated colors as perceived by a color blind person. . . . . . . . . . . . . . 21

3.22 The idea of using icons was conceived during a brainstorming session. . . . . 21

3.23 Comparison of trash icons from LisaOS (1987) and Windows 7 (2010). . . . . 22

3.24 Downscaled and desaturated images used as first iteration of icons. . . . . . . 23

3.25 Complete set of icons from the first iteration of icon design. . . . . . . . . . . 23

3.26 First set of icons when inserted in a Gantt chart. . . . . . . . . . . . . . . . . 24

3.27 Common pictograms found all over the world. . . . . . . . . . . . . . . . . . . 25

3.28 Six of the trend setting pictograms from Munich 1972 by Otl Aicher . . . . . 25

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vi LIST OF FIGURES

3.29 Pictograms from the Olympic games in Beijing 2008. . . . . . . . . . . . . . . 26

3.30 Icons from second iteration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

3.31 Second iteration of icons inserted into a Gantt chart. . . . . . . . . . . . . . . 27

3.32 Example toolbar from the Mac OS X Human Interface Guidelines (page 108

in[14]) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

3.33 Third and final set of icons produced in the third and final iteration of icon

design. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

3.34 Icons from third iteration inserted into a Gantt chart. . . . . . . . . . . . . . 29

3.35 Summary of all three iterations of icon design. . . . . . . . . . . . . . . . . . 30

3.36 Gantt chart with progressbars and time line. . . . . . . . . . . . . . . . . . . 31

3.37 Gantt chart with a progress line instead of progress bars. . . . . . . . . . . . 32

3.38 Progress line with red and blue colored areas. . . . . . . . . . . . . . . . . . . 32

3.39 Collision in current Gantt chart results in stacked activitites. . . . . . . . . . 33

3.40 Stacked activitites. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

3.41 Delayed activity lifting the succeeding one like a wedge. . . . . . . . . . . . . 34

3.42 Delay visualisation resembling a car crash. . . . . . . . . . . . . . . . . . . . . 34

3.43 Delay extending vertically. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

3.44 Divergent color to highlight overlap. . . . . . . . . . . . . . . . . . . . . . . . 35

3.45 Shifting succeeding activitites forward in time. . . . . . . . . . . . . . . . . . 35

3.46 Final solution using both colored area and time shifting . . . . . . . . . . . . 36

3.47 Gantt chart used for delay scenario. . . . . . . . . . . . . . . . . . . . . . . . 36

3.48 Here a 30 minute delay have consequences on all three rows. . . . . . . . . . . 37

3.49 If the delay is 75 minutes long blasting is affected on the first row . . . . . . . 37

3.50 The activity chain shows the schedule for a selected machine in the Gantt

chart. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

3.51 Hotdog style visualisation of transportation time in Gantt charts. . . . . . . . 39

3.52 Default progress line in Microsoft Project 2010, shown in red color. . . . . . . 40

3.53 Our progress line. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

3.54 Process flow diagram of the mining processes . . . . . . . . . . . . . . . . . . 42

3.55 Process view objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

3.56 First version of the process view . . . . . . . . . . . . . . . . . . . . . . . . . 43

3.57 Second version of the process view . . . . . . . . . . . . . . . . . . . . . . . . 43

3.58 Third version of the process view . . . . . . . . . . . . . . . . . . . . . . . . . 44

3.59 Material tracking in the process view . . . . . . . . . . . . . . . . . . . . . . . 44

3.60 The two-dimensional map view in the concept demonstrator . . . . . . . . . . 45

3.61 Gantt view implemented in the concept demonstrator . . . . . . . . . . . . . 46

Chapter 1

Introduction

The mining industry has recognized the need for streamlining the production using modernprocess control systems. The goal is to increase the efficiency, save energy and reduce theamount of people needed to operate a mine. ABB is providing the engineering expertiseand technological development needed to achieve these goals.

Current process control systems are lacking many important features which preventseffective usage in future underground mines. Soon, sensors will be introduced undergroundthat can measure and track many different aspects of the mining processes. This will placehigh demands on visualization of resources, but also on effective work scheduling and simpleto use mine maps.

The future process control systems for the mining industry also requires an adaptedgraphical user interface (GUI) that is user-friendly yet innovative and technologically ad-vanced. The goal of this project is to develop a concept demonstrator with a GUI opti-mized for operators in future underground mines. The GUI should provide a comprehensiveoverview of all activities in the mine, including the progress of ongoing production processes,and provide a usable toolset for the mine operator when supervising humans, vehicles, min-ing activities and other resources. The end-result will be used as a platform for ABB whendiscussing internally and externally with partners, but it also represents an important step-ping stone for the development of future products in the field of process automation for themining industry.

Due to shortage of various resources, such as real end users, access to the currently usedsoftware and access to the real context, the preparatory work will be based upon field studiesthat ABB has done in beforehand. These studies include taped observations of an operatorperforming work at an underground mine and other important information. Evaluations ofthe end-result have not been performed because of these limitations.

Results include a user interface solution for multiple screens that contain a Gantt chartview for planning, a 2D geographical map of the mine for resource tracking and a traditionalprocess view for visualization of ore movement. These particular user interface solutions havealso been implemented in a conceptual demonstrator. Generally, a strong focus has beenplaced on concept generation and innovation which has resulted in a large amount of ideasand suggestions that has yet to be properly evaluated. Hopefully, these results can providea basis for discussion and future research in this area.

An action research methodology was applied in this thesis project, meaning that weacted both as designers and researchers, and the stakeholders were tightly involved in theprocess participating in design decisions. This way the design process and methodology

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2 Chapter 1. Introduction

applied including its limitations could be evaluated and discussed from the perspective ofthe dual and sometimes conflicting roles of being both designer and student/researcher.

1.1 ABB

Asea Brown Boveri (ABB) is a leader in power and automation technologies that enableutility and industry customers to improve performance while lowering environmental im-pact. The ABB Group operate in around 100 countries and employ about 130,000 people.ABB specializes in five major areas; Power Products, Power Systems, Discrete Automation& Motion, Low Voltage Products and Process Automation. Global ABB Corporate Re-search has the aim to develop technologies for future products and services for ABB’s corebusinesses.The main focus is on Process Automation with emphasis on providing customerswith products and solutions for instrumentation, automation and optimization of indus-trial processes. Customer’s key benefits include increased production efficiency and energysavings.

Chapter 2

Methods

The work of this thesis is roughly divided into three phases: the research phase, the ideageneration phase and the concept realization phase. The methods used during these phasesare described under the corresponding subsections below.

The first thought was to apply the traditional process of User Centered Design in thisthesis, but due to the lack of a definite problem specification and real end-users such processhad to be excluded. Instead, in order to satisfy both the need of the stakeholders (with aproduct) and the academia (with relevant research), an action research methodology wasapplied in this thesis. This way, both of the needs could be fulfilled.

2.1 Assessing the User Context and Requirements

Before the work could start it was necessary to acquire the related domain knowledge.Mining is a vast field that encompasses many different areas and we chose to focus onunderstanding the mining processes in a Swedish underground mine. We also identified theneed of finding an appropriate method or framework for tackling a complex project like this.

ABB had already done field studies in a mine which provided a good source of informa-tion. Included in these studies were recorded observations from a mine operator in his work,as well as role descriptions of the workers in the mine. These two parts were extremelyvaluable, since it helped us understanding the underlying problems and their sources.

First, we began to study the role descriptions. To clarify the paths of communicationbetween the people involved in the mine, a simple graph was created to visualize the roledescriptions. From this, we understood that the current relationships between the work-ers and the operator is unnecessarily complex which results in unnecessary and inefficientcommunication.

The other important source of analysis was the recorded sessions of a working operatorthat were available from field studies. Since we did not have access to real end-users,these videos very valuable because they provided a valuable account of an operator andhis work context. But since these recordings contained raw data, we needed to organizethe analysis in order to have a broad and useful basis without unnecessary information.The tool that helped us with this was the Activity Checklist [18] from the Activity Theory[17] [7], a cross-disciplinary framework for studying different forms of human practices asdevelopment processes, both individual and social levels interlinked at the same time [26].By using this, we could determine a number of questions to answer during the film analysis.The questions are listed below.

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4 Chapter 2. Methods

– How do they interact with the system?

– Are there any shortcuts they have to take for reaching certain features? If so, whatshortcuts?

– Is there any support in the system (e.g. colors, etc.) to achieve different goals or doesthe experience of the operator count? Or does a combination of them both have to beapplied?

– Do they have to use tools outside the system? If yes, what tools?

– Does conflicts arise between different actions?

– Are there any distractions? If yes, what?

– Other general observations

2.2 Idea generation

Brainstorming and other creative techniques were used to come up with innovative solu-tions to the problems experienced by the mine operators. In addition to classical brain-storming, imaginary brainstorming and negative brainstorming [25] was used to produce alarge amount of solutions. These ideas addressed the many different issues we had and werelargely independent.

ABB has a tradition of using scenarios, personas and use cases to define new functionalityand address both user needs and business goals when developing new products. In thisproject, the lack of target user involvement made the use of personas ineffective. Insteada limited set of key scenarios and use cases were created. Scenarios tell what happens in aspecific situation without concentrating on details, instead the goals and behaviors of thetarget user in the real world are taken into account [31]. With these, everyone involved inthe project could establish a common ground.

2.3 Concept generation

Inkscape, and open source vector graphics software, was used to draw new user interfacecomponents which were then exported to the XAML file format used by Microsoft ExpressionBlend. Using Expression Blend, these components were used to create the final conceptdemonstrator.

Chapter 3

Results

In this section, the results from the main phases of the project are described in detail. Onlyresults from the research phase and the idea generation phase are taken into account, sincethese were the productive phases.

3.1 Assessing the User Context and Requirements

The role descriptions were visualized in order to simplify analysis and find patterns in thepaths of communication. Figure 3.1 shows the resulting graph. Identified problems werethat the leadership is not outspoken and the responsibilities are not organized, resulting ina major problem: the communication between the workers and the operator is poor, leadingto incorrect decisions and duplication of work. This deficiency is further supported by theuse of a non-directional radio link as the only means of communication.

Using these questions when analyzing the films, a large amount of unstructured ideasand thoughts were produced. These were organized into a manageable set of areas countedas major problems. Some of the most important problem categories are presented below.

CommunicationWorkers are basically shouting out important information on the radio link without ad-dressing it to anyone special. The operator has to pay close attention to what is being saidand update the Gantt chart accordingly whenever the schedule for an activity is affected.Another common problem is that workers sometimes forget to report finished activities andother events, only to be recognized when their shift has ended. Such important informationis vehicle damage, delays of various kinds, etc.

Limited support by softwareThe operator’s experience is overlooked, the help received from the current software is lim-ited and it lacks many important functions that could support him when decisions need tobe made. For example, the operator is not getting any help to determine distances betweenlocations in the mine, or suggestions on what to do in case of delays. Colors are being usedin the Gantt chart to show the activity type and to signal if an activity is completed or not,but because of excessive usage of many different highly saturated colors, the user interface isvisually cluttered. Also, the choice of colors is poor and does not follow recommendations,such as representing danger or warnings using red color and blue for security etc.

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6 Chapter 3. Results

Production Foreman

Electrician

Mine Mapper

Rock EngineerOperation Center

OperatorMachine Operators

Production Manager

Construction Foreman

ConstructorsSubconstructors

Mobile Machinery Foreman

Storage responsible

Mobile machinery

group

Diamond Drill

Drillers

Ore Mapper

Mine Engineer

Environmental Coordinator

HQEnvironmental

worker

Safety worker

Figure 3.1: The the roles as we understood them. The arrows represent the communicationdirections between roles.

3.2. Visualisation and concepts 7

Manual updatesA static map software which has to be manually updated is used for monitoring an ac-tive production point, and a static Gantt chart with the time span of one week shows thescheduled activities for each production point in the mine. Beside showing activities at aproduction point, the Gantt chart has views for pockets and vehicles. All updates in theGantt has to be performed manually as well.

Non-integrated toolsThe computer system used by the operator consists of several non-integrated software ap-plications, each used for different tasks. Several physical artifacts are used as complementsto the computer system as well. This forces the operator to move focus away from the mostimportant tasks such as planning and monitoring activities.

One of the physical artifacts is a physical map that is hanging on the wall behindthe operator’s seat. It is used primarily by new operators to determine distances in theunderground mine. Quote from an operator: “Conny [another operator] has never been in amine, he does not know how long it takes to get from one place to another. Me on the otherhand, I know such information because I have been working underground for many years”.The difference between the physical map and the digital map is that the former is used todetermine distances between points in the mine, and the latter is used for monitoring theproduction point that is currently active.

Post-it notes are used extensively as memos attached to the computer screen edges. Itcould be something the operator picked up from the radio, something he / she has not hadtime to update the system with at once, something that needed to be forwarded to the nextshift, etc.

Figure 3.2: The Gantt chart software currently used

3.2 Visualisation and concepts

The concepts shown in this section are based on the results from the research phase. Sinceeach concept is an attempt on providing an acceptable solution to one or several problemsfound during the research phase, they should only be considered as suggestions and not asfinal solutions.


Figure 3.3: The physical map hanging on the wall behind the operator

Figure 3.4: The map software currently used


The “3D mine model” concept presented in this section was initially not aiming to solveany specific problems other than acting as a reference for the thesis group when workingwith the project. But when the demonstrator was in development, this model was takeninto account and suggested to be used as a tool showing the main structure of the mine andshowing statuses of different parts in the mine with real time updates. Thus partly solvingthe “Limited support by software”, “Communication” and “Manual updates” problemsidentified during the research phase by giving the operator a real time overview of theoperations in the mine.

Problems with the system not being supportive to the operator was identified during theanalysis of the video tapes during the research phase, i.e. the operator does not get any helpto determine distances between locations in the mine, or get suggestions on what to do incase of delays. In such case, the “3D to 2D” concept would be an acceptable solution if it isdeveloped further. With the use of this map, the operator could get help with determiningdistances. Another problem that this concept would solve is the “Non-integrated tools”problem. With having a digital map as a part of the system, the operator would not haveto use an external physical map and thus not having to move focus away from the mostimportant tasks such as planning and monitoring activities. The system would be unified.

The concepts presented under the “Visualization of movement”, “Vehicle and resourcevisualization” and “Visualization of toxic gas” sections have been aimed at solving the“Limited support by software” and “Manual updates” problems. By visualizing the statusof important conditions in the mine, updated in real time, the system could support theoperator in different events.

3.2.1 3D mine model

A simple but representative 3D model of a mine was created from scratch to be used as areference point during the project. After trying out various 3d modeling software, Blenderwas chosen because it was open source and supported easy scripting using the Pythonprogramming language. Maya, 3D studio Max and Sketchup were some of the alternativesthat were rejected because of high costs or too limited features.

The studied mine was the main source of inspiration when creating the 3D model. Afirst prototype version was created without much care to the details. A rendered image withthis model is shown in Figure 3.5.

Figure 3.5: A rendered image of the 3D mine model

When presenting this 3D model, the idea of integrating it with an existing MatLabsimulation of a ventilation system was conceived. However, an evaluation showed that


in order to use it for simulations, large structural changes was needed to make it moreauthentic. A second mine model shown in Figure 3.6 was therefore created with a structurethat was adapted to the parameters of the ventilation simulation.

Figure 3.6: Screenshot from Blender showing a wireframe version of the 3D mine model

In this model, all nodes and sections have been tagged with a name that defines itsfunction or resource type. Fans, gates, storages, faces, crushers and hoists have been labeledto produce a mine model that could be used in an advanced mine simulation.

Using a Python script in Blender, all structural and logical information could be ex-ported. The screenshot in Figure 3.7 comes from the simulation software and shows thefinal 3D model running an ore tracking simulation.

3.2.2 3D to 2D

Navigating in three dimensions is easy for humans, but doing so on a 2D screen is oftenunintuitive and challenging for a novice user. Facing this, a method for converting a 3Dmap of a mine to a 2D image for easy browsing was investigated. Normally reducingdimensionality always leads to a loss of information. The goal is hence to find a mappingfrom 3D to 2D that retains as much usable information as possible.

Studying underground mines reveals that the individual levels often are relatively flat.This provides an excellent opportunity of reducing dimensionality while preserving most thegeographical information. By flattening the levels completely and laying them next to eachother, a 2D representation was created, as shown in Figure 3.8.

This technique was used to create a map view in the final demonstrator, but a fewalternative solutions was explored as well. The concept in Figure 3.9 is using 2D images ofthe individual levels that are stacked on top of each other to preserve some of the depthinformation. In a strict sense this would probably count as a 2.5D representation.

The 3D mine model was created in Blender using only straight lines and points, andcould therefore be interpreted as a graph. Realizing this opened up for automatic layouttechniques used in the field of graph drawing. Automatic layout algorithms are used to


Figure 3.7: Screenshot from ABB’s simulation software showing the imported 3D minemodel

Figure 3.8: 2D mine map created by flattening out the 3D model


Figure 3.9: Stacked 2D planes preserving some of the depth information


rearrange graph nodes to minimize edge overlaps while preserving large scale structures. APython script was created to export the 3D mine to the GraphML file format which couldthen be opened with Gephi, an open source 2D graph visualization software that implementsseveral automatic layout algorithms. The image in Figure 3.10 was created by running the‘Huyifan’ layout algorithm after importing the GraphML file in Gephi.

Figure 3.10: 3D mine model after applying an automatic 2D graph layout algorithm

The result is an organic two dimensional graph that bears little resemblance to its source.Even though most geographical data is lost, it was argued that this visualization techniquewas very interesting and could perhaps be developed to be a viable solution to the 3D to2D mapping problem. Many defining properties of the mine still remain intact. When usedfor navigation for example, the map’s most important function would probably be to showwhich direction to take when reaching an intersection. The map would also be a good toolfor estimating distances, but that would require the edge lengths to be preserved, which isnot done when using the ‘Huyifan’ layout algorithm.

3.2.3 Visualization of movement

The map view allows an operator to track vehicles in real time. Such feature obviouslyraise concerns regarding privacy and integrity, but it would certainly prove useful in casesof emergency. Eight concepts for visualizing vehicle movement is presented in Figure 3.11.They have been developed to show the recent path of movement for a selected vehicle.

3.2.4 Vehicle and resource visualization

The map view could be used to track resources, but showing all vehicles and personnel at thesame time would introduce a lot of visual clutter and compromise the privacy of the peopleworking in the mine. To solve this, a group based resource visualization was proposed.

This concept avoids singling out a particular person by merging people and vehicles intogroups. Groups are represented by circles with indications of how many people and vehiclesthey contain. Hovering the mouse over a group make it expand into smaller sub-groups


Figure 3.11: Concepts for visualization of vehicle movement in a mine map

which can be expanded again to show new sub-groups. The smallest subgroup represents asingle vehicle or person which can be identified in more detail.

This approach provides useful resource tracking while minimizing the intrusion on work-ers’ privacy. As a positive side effect, outliers are easily detected, which can be seen in theimages in Figure 3.12 where a single vehicle is moving outside the bigger sphere.

3.2.5 Visualization of toxic gas

Sensors are continuously measuring the levels of toxic gases to ensure high air qualitythroughout the mine. Fires and emissions from vehicles and are two common sources oftoxic gases that pose a threat to the health of the machine operators. The map view wouldbe a natural place to show the gas levels.

The concept in Figure 3.13 is visualizing three different types of gases using a pointcloud. Each type of gas has a different color so that high concentrations of gas is shown byan increased number of points in the corresponding color. This allows an operator to quicklyassess the geographical location of a gas outbreak as well as its magnitude and distributionof different gases. It also makes it easy to follow the movement of gas in real time to ensurethat the ventilation system is operating as expected.

Today the number of gas sensors in the studied mine are limited to one on each level, andthey are not fast enough to provide continuous live updates. When facing these conditions,the concept in Figure 3.14 could be a better solution. Small bar charts are displaying thegas levels and clicking one of them opens a more detailed view. This approach is moreflexible and could be used to visualize other types of resources as well, providing a smootherintegration with the map.


Figure 3.12: Concept for vehicle and resource tracking

Figure 3.13: Gas concentration visualized as a point cloud

Figure 3.14: Bar chart visualization of gas concentrations


3.3 Work scheduling using Gantt charts

The operators in the studied underground mine use a Gantt chart to create and maintainthe work schedule for all the machines that are part of the drill-and-blast cycle. This sectiondescribes the process of developing an improved Gantt chart which relies on icons instead ofusing colored backgrounds and text labels to indicate the type of activity. Three iterationsof icon designs are evaluated and discussed. A technique for showing the progress of Ganttactivities is also described, followed by a discussion on visualizing activity collisions anddelays. Moreover, a concept for tracking individual machines in the Gantt chart called Ac-tivity chain is presented, as well as an example of visualizing transportation time. However,before presenting these results, an introduction to Gantt charts is given.

3.3.1 Introduction

Increased automation and better resource utilization is central in the development of thefuture mining industry. This will have effects on all aspects of the production process,including schedule planning. Today planning is still performed manually by the operatorsin many mines. In the future, sensors will help them keep the schedule updated by providingposition tracking and live progress reports. In the studied mine, a Gantt chart is being usedfor schedule planning. This section describes the process of designing a new Gantt chart thattakes advantage of sensor data to enhance the user experience and create a more streamlinedscheduling interface.

The basic Gantt chart

A Gantt chart is a type of horizontal bar chart that is often used in project management tographically display the relationship between tasks in a project[32] . Gantt charts are usuallyconstructed with a horizontal axis for time and a vertical list of tasks, each represented bya single bar on the time line that shows the planned starting and ending time. Figure 3.15shows an example of a typical Gantt chart for a design project.

History

Gantt charts have been used in their current form for almost 100 years. In his seminal1913 book on work management, “Work, Wages & Profits”, Henry Gantt introduced thesecharts as a graphical approach to representing project management and work processes. Thebook was originally targeting employers in the manufacturing industry and describes howto optimize labor and maximize profit using a bonus system that rewards efficient workers.Gantt charts are used as a visual tool to organize and follow up on tasks divided amongworkers. Figure 3.16 shows one of Henry Gantt’s earliest charts used in a machine shopevironment producing parts for locomotives[9] .

Some sources credit polish engineer Karol Adamiecki for inventing the Gantt chart al-ready in 1896[22] . In Adamieckis “Theory of Work Harmonization”, a graphical solutionto production scheduling called “Harmonograf” is described that is very similar to Ganttcharts. Despite this, it was Henry Gantt that popularized the chart and it hence carries hisname today.

Modern Gantt charts

Gantt charts are a natural part of modern project management and have changed little sincetheir first appearance. Since 1913 a few extensions have made them even more powerful and

3.3. Work scheduling using Gantt charts 17

Figure 3.15: A typical Gantt chart.

Figure 3.16: One of the very first Gantt charts produced by Henry Gantt.


universal. One way of enhancing the functionality is to utilize the bar area more efficiently,for example by using it as a progress bar. This is an elegant visualization that is easy touse and understand. An example is shown in Figure 3.17, where light gray color is used torepresent the progress of unfinished activities:

Figure 3.17: Typical Gantt chart with progressbars.

The screenshot in Figure 3.18 shows the graphical interface of Microsoft Project 2010, aproject management software that has a Gantt chart implementation with many extensions.A few of them are visible in this screenshot, for example task grouping which used to simplifycomplex projects[32] - shown as a dark gray horizontal bar that span all subtasks. Anotherextension is the visualization of task dependencies using arrows to indicate that a task hasto be fully completed before the following task can start.

Gantt charts in mining today

Gantt charts are perhaps the most commonly used tool for production scheduling today[12].This section is based on recorded video information gained from field studies in a singlemine in Sweden where Gantt charts are a vital part of the mine operator’s work. Thestudied mine is relatively small with about 20 production points. It is managed from aground level control room by a mine operator using a proprietary Gantt chart software forscheduling and a handheld transceiver for communicating with workers. Because of theunpredictable nature of mining, delays are frequent. This makes it very difficult to createaccurate schedules for the machines involved in the drill-and-blast cycle. The mine operatoris therefore continuously listening to the radio communication between machine operatorsin order to track the progress and perform manual updates to the Gantt chart. Figure 3.19shows a partial reproduction of the Gantt chart used by the mining operators in the studiedmine. Each row corresponds to a production point with different activities represented asrectangular blocks placed on the horizontal time line.

The red vertical lines represent blasting. During this period of time, no personnel canremain near production points and must be evacuated to the lunch room. Blasting occursthree times every day with eight hours in between, an activity that cannot be postponed.


Figure 3.18: Microsoft Project has an advanced implementation of the Gantt chart withmany extensions.

Figure 3.19: Reproduction of the Gantt chart used in the studied mine.


This means that if a blasting gets delayed by only a few minutes, the whole mining processwill be delayed eight hours for that production point.

When used in project planning, Gantt charts usually have only one planned activity perrow. This results in low utilization of the available screen space, which is one of the usuallypointed out problems with Gantt charts. Here, the rows are representing production pointsand therefore contain several activities. This greatly improves the utilization of screen spaceand allows for a more compact and efficient visualization.

Gantt schedules in mining tomorrow

One of ABBs goals is to make the mining industry more automated. Fully automatedschedule planning will be possible some day, but until then, the studied mine will continuedoing their planning manually using traditional Gantt charts. Some parts of ABBs miningproject have come much further in their development and will be available in only a fewyears time. Making use of these features in a Gantt chart could simplify the work for theoperators, for example by providing live progress reports for assisted or semi-automaticrescheduling.

3.3.2 Icons instead of text

A brief evaluation of the Gantt chart currently used in the studied mine has been performed.Some of the problems found have been addressed in order to improve the usability of futureGantt charts used by the mining industry, notably by replacing text and color coding ofactivity types by icons.

Use of color current Gantt chart

Each activity in the drill-and-blast cycle is represented in the studied Gantt chart witha rectangular block, as shown in Figure 3.20. In total there are nine different activities.Besides a defining text, the background color of the blocks also maps to the type of activity.However, the choice of colors is poor. The colors used for “Charging” and “Shotcreting”are shades of pink that are hard to distinguish between. “Scaling” and “Scraping” suffersfrom the same problem using similar shades of turqoise-green. Viewed on an old computerscreen or in bad lighting conditions, these colors could be impossible to separate.

Figure 3.20: Colors used in Gantt chart in the studied mine.

Around 8% of the Caucasian male population is color blind [13] and have trouble discrim-inating red and green hues[30]. Several free tools exist for converting standard rgb-imagesinto a color space as perceived by color blind people. Viewing the image in Figure 3.20 inthe eyes of a deuteranopic reveals an even more subtle differentiation of colors which makesit hard to distinguish the background color of “Flushing” from the ones of “Charging” and“Shotcreting”, as shown in Figure 3.21.


Figure 3.21: Simulated colors as perceived by a color blind person.

Icons

The idea of incorporating icons in the Gantt chart came up during a productive brainstorm-ing session. Today, the operators are facing massive amounts of text when browsing theirGantt charts. Why not replace that text with small icons instead?

Figure 3.22: The idea of using icons was conceived during a brainstorming session.

Representing activity types using well-designed icons could eliminate the need of boththe describing text and the color coding. According to the Digital Accessibility Team[34] ,icons compared to text labels have the advantage of being:

– more distinctive;

– more efficient for denoting spatial attributes;

– easier to recognise and remember over long periods of time;

– easier and faster to learn when the size of the symbol set is small; and

– language independent

However, as pointed out before, good icons are very hard to produce, and in this case ittook three attempts before a suitable set of icons was developed.

Evaluation guidelines for icons

Since their public introduction in the 1980s desktop computers, icons have gradually changedfrom being low resolution black-and-white pixel bitmaps to the colorful and often near pho-torealistic vector images seen today. The image in Figure 3.23 demonstrates the evolutionof the trash icon, showing a screenshot from Apple’s 1983 operating system LisaOS, nextto a high resolution icon for the 2010 Microsoft Windows 7 recycle bin.


Figure 3.23: Comparison of trash icons from LisaOS (1987) and Windows 7 (2010).

Despite the dramatic visual differences, the original trashcan metaphor employed byApple almost thirty years ago is still being used unchanged. Even though Microsoft addsanother dimension to the concept by the notion of “recycling” the hard disk space usedby deleted files, this shows the timelessness of a well-chosen metaphor. There are manyguidelines for successful icon design and most of them point out the importance of findinggood metaphors. Other common recommendations include [20, 23, 14, 1, 15, 34, 29]:

– Make icons easily distinguishable. Icons with unique outlines are easy to identify.

– Simplify. Reduce the visual complexity by removing unnecessary details.

– Strive for consistency. Within a set of icons the visual style should be coherent.

– Restrict the use of color. Color draws attention and should signify a meaning ifpresent.

First iteration

The first icons were almost direct renditions of the machines responsible for the differentactivities. The motivation for this lied in the belief that the operator was already thinkingof the physical machines when planning the schedule. Laziness was another factor, since thepictures used were already available from earlier work, and coming up with new effectivevisual metaphors was considered too difficult and time consuming. One of the primaryrequirements for the new Gantt chart was to minimize the number of different colors andonly use vivid colors for critical functions such as alarms. Because of this, the icons weredecided to be desaturated or in grayscale.

The images in Figure 3.24 were originally drawn to be used in lo-fi prototype work, hencethe simplified graphical style. By reducing size and contrast and inserting white contours,these images were converted to grayscale icons. No further adjustments were made, exceptmirroring some of the images horizontally to ensure they were facing the direction of thetime line. The complete set of icons is shown in Figure 3.25.

Evaluation of first iteration

When evaluating icons it is important to do so in the context of the real user interface [27].Therefore, the icons were inserted into a Gantt chart shown in Figure 3.26 for a quick andinformal heuristic evaluation using the guidelines above.


Figure 3.24: Downscaled and desaturated images used as first iteration of icons.

Figure 3.25: Complete set of icons from the first iteration of icon design.


Figure 3.26: First set of icons when inserted in a Gantt chart.


The initial impressions were that the icons are easily distinguishable, but that they needmore work. Too much detail and inconsistent style are the main issues that need to be

corrected. There is also a problem with their size, the drilling machine for example is tootall and becomes very small when resized to fit the surrounding activity boxes. However,compared to the original text based Gantt charts, these icons were considered to be a bigimprovement which further motivated a second iteration of icon design.

Second iteration

When designing the second set of icons, pictograms were the primary source of inspiration.Pictograms are symbols that represent an object or concept and are often use in publicsigns. Unlike icons, pictograms are often designed according to official standards to ensurecomprehensibility, discriminability, learnability, legibility and recognizability[15]. Some pic-tograms have become universal standards, such as the ones displayed in Figure 3.27[1] .

Figure 3.27: Common pictograms found all over the world.

Olympic pictograms are used to symbolize the individual sports in the Olympic Games.They have been used since 1936 and are often created in a visual style that is representationalfor the hosting country. Figure 3.28 and 3.29 are examples of the classic pictograms fromthe summer games in Munich[24] 1972 and the designs from the 2008 Olympic Games inBeijing[8] which were inspired by written Chinese characters .

Figure 3.28: Six of the trend setting pictograms from Munich 1972 by Otl Aicher .

The activity icons were completely redrawn to resemble pictograms rather than moderncomputer icons. Instead of showing the actual machines performing their work, represen-tative aspects of the mining activities were visualized, e.g. a bolt representing the activityof bolting. Using common real-world objects in icons are often preferred by both noviceusers and experts [29], and in this case, it also provides an opportunity to reduce the visualcomplexity of the icons.


Figure 3.29: Pictograms from the Olympic games in Beijing 2008.

Only black and white colors are used with the goal of producing a more elaborate setof icons with a consistent style. Generally, increased contrast between icons and theirbackground also has the advantage of enhancing the distinctiveness and speeding up searchtasks [20]. Although the end result shown in Figure 3.30 is arguably more visually appealingthan the first set of icons, another heuristic evaluation was needed to determine their successin a Gantt chart.

Figure 3.30: Icons from second iteration.

Evaluation of second iteration

Placing the icons in a Gantt chart, as shown in Figure 3.31 reveals that some of the detailis lost because of their small size. They are not as easily distinguishable as the first set of

icons, in fact the icon for cleaning and shotcreting have a silhouette that lookvery similar when performing a simple squint test.

These icons make extensive use of highlights to imply three dimensional forms. Eventhough this has certain esthetical qualities, when viewed in this Gantt chart it also leads tovisual clutter. Reducing the use of white highlights and small details, as well as reducing the


Figure 3.31: Second iteration of icons inserted into a Gantt chart.


overall contrast, would probably be an improvement. No real user tests were made, but thenew icons were still considered to be easily recognizable by all people that were presentedwith this image. A third and final iterations of icon design was therefore performed tocorrect the issues found.

Third iteration

Both the first and the second set of icons were too detailed and had too complex shapes.One of the reasons for this is that the icons were designed at a much higher resolution thanwhen viewed in the Gantt chart. Ideally icons of this size should be created in a rasterimage editing software where one has full control over the individual pixels, such as AdobePhotoshop. There are special guidelines for designing small icons, namely those adapted fortoolbar icons. In the Mac OS X Human Interface Guidelines they stress the importance ofusing a straight-on perspective and keeping sharp and clear outlines when designing smalltoolbar icons[14] . They use the image in Figure 3.32 as an example

Figure 3.32: Example toolbar from the Mac OS X Human Interface Guidelines (page 108in[14])

Microsoft also has specific guidelines for toolbar icons. Besides stating that small iconsshould be simplified for increased readability, they also establish that “as an icon getssmaller, transparency and some special details found in larger sizes should be sacrificedin order to simplify and get the point across”[23] . When designing Action bar icons forAndroid mobile phones, Google recommends using “smooth curves or sharp shapes”[10] .Action bar icons are small (32x32 pixels) grayscale icons that correspond well to computertoolbar icons in both form and function. Using these recommendations the third and finalset of activity icons was created, as shown in Figure 3.33.

Figure 3.33: Third and final set of icons produced in the third and final iteration of icondesign.


Evaluation of third iteration

In these icons, shown in Figure 3.34, unnecessary details have been removed and the per-spective is flat. The overall shapes are simpler and there is a clear consistency within theset. The symbol for hauling has been changed from a loader bucket to a traditional mine

cart , providing a widely recognized silhouette that is easily distinguishable.

Figure 3.34: Icons from third iteration inserted into a Gantt chart.

Because of the simplifications, the meaning of some of the symbols is likely not as clearanymore. The drilling icon could perhaps be misinterpreted as a fallen tree, and the

cleaning symbol , which is supposed to look like rocks falling from a mine ceiling, could

also be hard to decipher. Moreover, the icon for shotcreting could easily be mixed upwith the icon for flushing .

Summary

Three iterations were needed to produce a good set of icons for representing activities in aGantt chart. This shows that icon design is hard and takes a lot of time, especially if youare not a professional graphic designer. The first set of icons was made up of downscaledversions of already existing images which resulted in too much detail and an inconsistentstyle. Small icons need to be carefully designed to optimize pixel usage by exaggeratingthe defining details[23] . The second set of icons was in a sense worse than the first one.Inspired by pictograms, these icons failed to communicate their message with the simplicityand clarity often seen in public signs and symbols. The third and final set of icons was createdwith the help of design guidelines for toolbar icons. Combined with the insights from the


earlier attempts, this approach was successful and resulted icons that were considered tobe simple yet easily discriminated. Unfortunately no evaluations with real users in a realwork context could be performed to confirm this. However, when presenting the resultsto a group of people from the mining industry, one of them could spot a planning erroronly a few seconds after seeing the Gantt chart for the first time. Combined with verypositive feedback, this could possibly indicate that the icons really are easy to recognize andunderstand. Figure 3.35 shows all three sets of icons for easy comparison.

Figure 3.35: Summary of all three iterations of icon design.

3.3.3 Visualisation of progress

In the near future, mining machines will be equipped with on-board sensors to measurethe performance and progress of the current activities. visualising this data in the Gantt


chart could provide an opportunity for the operator to perform early rescheduling and otheradjustments to the Gantt chart in order to optimize time and resources. A common way ofvisualising progress in Gantt charts is to use the background area of each activity to displaya progressbar. Figure 3.36 demonstrates how this could look using a dark gray color forfinished activities and white for unfinished activites. A vertical dotted line represents thecurrent time.

Figure 3.36: Gantt chart with progressbars and time line.

Experience gained during this project has shown that this way of displaying progressbecomes less effective when the number of rows in the Gantt chart increases. Getting anoverview of the general progress is difficult, even for small mines with only 20 scheduledproduction points. A possible explanation could be that this visualisation has a tendencyto steer focus towards individual lines rather than to the general deviation from the verticaltime line. Removing the small gap of air between the rows would improve this, but thenthe rows would become hard to separate.

Progress line

Facing this problem, a simple and effective solution was found. Instead of using progressbars, a second vertical line was inserted in to the Gantt chart which followed the progressfor the shown activities, as displayed in Figure 3.37.

It is now very easy to assess the overall progress simply by comparing the vertical timeline with this second progress line. If the progress line shifts to the left of the time line, anactivity is delayed, and equivalently, a shift to the right means that an activity is ahead ofschedule. This effect can be further augmented by coloring the areas between the time lineand the progress line, as shown in Figure 3.38.


Figure 3.37: Gantt chart with a progress line instead of progress bars.

Figure 3.38: Progress line with red and blue colored areas.


Unlike the traditional way of visualising progress in Gantt charts using progress bars,the progress line does not introduce any significant visual clutter. Thanks to the powerof human vision this solution scales extremely well and facilitates a deeper exploration ofunderlying trends of progress. One drawback is that all previous activities on the row needto be completed for this solution to work. However, in this particular context, each activityin the drill-and-blast-cycle is dependent on the previous one, making this problem highlyunlikely to ever occur in practice.

3.3.4 Visualisation of delays and schedule collisions

The mining process depends on many uncontrollable factors which makes planning extremelyhard. Delays happen all the time, in fact one of the main functions for the operators inthe studied mine is to continuously update the Gantt chart to accurately reflect the currentproduction status. When delays occur, two activities could end up occupying the same spaceon the time line. The Gantt chart software in the studied mine solves this by stacking theboxes that represents the concerned activities, as shown in the middle row in Figure 3.39.

Figure 3.39: Collision in current Gantt chart results in stacked activitites.

Alternative visualisation techniques for activity collisions in Gantt charts have beendeveloped in this thesis. Creative techniques were used to produce a large amount of differentideas which later could be sorted, merged and developed in to a few interesting conceptswhich are presented here. In the following images, dark gray color represents a delayedactivity that has been extended to overlap the succeeding activity which is represented bya light gray color.

Figure 3.40: Stacked activitites.

The first concept shown in Figure 3.40 is identical to the one already being used in thestudied mine. Delayed activities produce a collision that is similar to the way one would


expect two physical boxes to stack on top of each other. This solution has the advantageof standing out since it doubles the height of affected Gantt rows. It also makes it easy tovisually estimate the amount of overlapping time. The double row height is also one of thedisadvantages of this approach since it leads to inconsistencies in the Gantt chart.

Figure 3.41: Delayed activity lifting the succeeding one like a wedge.

The second concept shown in Figure 3.41 is similar to the first one. Here, the physicalproperties of the activity boxes are taken even further. The delayed activity pushes throughand lifts the succeeding activity like a wedge. By mimicking the laws of physics, thisapproach may at least in some sense be perceived as simple or even natural. In practicehowever, the non-orthogonal lines produced by this visualisation would probably cause visualclutter and distraction in a Gantt chart.

Figure 3.42: Delay visualisation resembling a car crash.

The third concept shown in Figure 3.42 is inspired by the collision of cars. It takes thephysical properties to the extreme by simulating a material that deforms in the collisionwith another activity. This visualisation is highly conceptual and would not be a viablealternative as it is, but the underlying idea is interesting and could be developed.

Figure 3.43: Delay extending vertically.

In the fourth concept shown in Figure 3.43 the delayed activity is extended verticallywhen it starts to overlap the succeeding activity. The amount of overlap is clearly visible and


it is easy to see which one of the activity that has been delayed. The biggest disadvantageof this concept lies in the fact that the protruding part is not following the direction of thetime line. This makes it unintuitive and ambiguous. Also, a lengthy delay would require alot of vertical screen space.

Figure 3.44: Divergent color to highlight overlap.

The fifth concept shown in Figure 3.44 uses an overlaid semi-transparent area in adivergent color to highlight the overlap. This visualisation requires little extra screen spaceand makes it easy to estimate the amount of time that overlaps two activities. Normallyred color is reserved to showing warnings and errors, but considering the implications ofmissing a scheduled blast, this could be an appropriate situation to use red color as well. Ifthe collision doesn’t affect blasting, yellow color could be used instead to be consistent withthe colors normally used in distributed control systems.

Figure 3.45: Shifting succeeding activitites forward in time.

Another way of dealing with overlaps is to avoid them completely. In Figure 3.45 , thedelayed activity shifts the succeeding activity forward in time instead of overlapping it. Anadvantage of propagating the delay forward in time like this is that the future implicationsof a delay can be seen directly. This would help an operator in an underground mine tobecome aware of delayed activities that risks causing conflicts with blasting later on.

Final solution

In the final demonstrator, a combination of the last two concepts for schedule collisions isbeing used to visualise the result of a delay. Instead of showing the amount of overlap,succeeding activities are shifted forward in time. This could be an appropriate solutionfor an underground mine where the activities at a production point always are sequentialand cannot be performed in parallel. The idea of using a semi-transparent colored area, asdemonstrated in the fifth concept above, has been used to highlight the delay rather thanthe amount of overlap. In addition, a text label has been inserted to show the actual lengthof the delay. This concept can be seen in Figure 3.46


Figure 3.46: Final solution using both colored area and time shifting

When used in a more complete Gantt chart, the ideas behind this visualisation can beextended to show the implications of a delay on other rows as well. Figure 3.47 shows anexample chart for three production points in an underground mine. In this image, only onedrilling machine is being used on all three production points, starting at production point3, then continuing to production point 1 and finishing at production point 2. After thedynamite is set, blasting occurs at production points 1 and 3.

Figure 3.47: Gantt chart used for delay scenario.

Figure 3.48 demonstrates a scenario where the drilling machine gets delayed for 30 min-utes while performing work at production point 3. As discussed above, this delay causesthe subsequent charging activity to be shifted forward in time. A corresponding delay hasbeen inserted just before the drilling activities at production points 1 and 2. Since blastingisn’t affected, yellow color is being used. The outlines are dashed to further distinguish thedelay visualisations from the activity blocks.

In case of a 75 minutes long delay, blasting will be affected. As shown on the top row inFigure 3.49 , the drilling activity at production point 1 is delayed 75 minutes, causing thesucceeding charging activity to interfere with blasting. Instead of yellow color, red is nowused to indicate the severe implications caused by this delay. Because of this the blastingactivity icon also has a red background color.

3.3.5 Activity chain

The operators in the studied mine use two Gantt charts when planning. One of them hasrows that correspond to production points where the activities in the drill-and-blast cycleare placed along the time line. The second Gantt chart is a reversed chart where eachrow corresponds to the schedule for one of the machines. Its main purpose is to allow the


Figure 3.48: Here a 30 minute delay have consequences on all three rows.

Figure 3.49: If the delay is 75 minutes long blasting is affected on the first row

operators to follow up on a specific machine to see its schedule and where it’s heading next.If the machine schedule could be incorporated in the main Gantt chart for production points,the need for a second chart would be reduced. One solution would be to draw connectinglines between the activities for a machine. Figure 3.50 show an example of this concept usinga thick gray line to represent the planned schedule for a machine responsible for blasting.

The smooth and organic curvature helps it stand out against the rest of the Gantt chartwhich mostly consists of straight lines. The part of the line that connects the second andthird activity box is colored red to indicate that something is wrong. In this case, it isa warning that there is not enough time for transportation between those two productionpoints. In the studied mine, failing to account for the transportation time needed is acommon problem that often leads to delays. This solution would not only reduce the needfor a second Gantt chart, but also help the operators achieve a more efficient planning byavoiding delays and clarifying dependencies between activities.

3.3.6 Vehicle transportation time

Before implementing the activity chain visualisation, an original idea for visualising trans-portation time was conceived during a brainstorming session. When using creative tech-niques, the resulting ideas are often silly and humorous, but with underlying qualities thatcan be developed further. The concept in Figure 3.51 was inspired by hotdogs to visualisethe transportation time needed for a machine to reach the next production point. Thesliced bun corresponds to a planned activity in a Gantt chart and the length of the sausageis proportional to the estimated time of transportation. When the operator responsible for


Figure 3.50: The activity chain shows the schedule for a selected machine in the Ganttchart.


planning has failed to account for enough transportation time, the sausage starts to bendagainst the succeeding bun. Even though this idea was left at a purely conceptual level, itis still a good example of how lateral thinking can help finding unexpected solutions to aproblem.

Figure 3.51: Hotdog style visualisation of transportation time in Gantt charts.

3.3.7 Related work

A majority of the ideas and visualisations found in this thesis are original work that wasproduced during a creative idea-generation phase with little help from existing literatureor research. However, history shows numerous examples of independent discoveries[36] andre-discoveries, and we make no claims of absolute novelty for the individual results presentedin this paper. In fact, one of the Gantt chart extensions has turned out to closely resemblea feature already available in Microsoft Project.

Microsoft Project progress line

Microsoft Project offers a similar approach to visualising progress in Gantt charts as theprogress line described in the results section. Microsoft’s implementation is also called“progress line” but lacks some important features of the progress line described here. Fig-ure 3.52 shows a screenshot from Microsoft Project 2010 with an enabled progress line shownin red color.

The basic concept is the same as our progress line - a vertical connected line that followsthe shape of each task’s progress, but the implementation leaves much to be desired. Bydefault, both the progress line and the time line is only 1 pixel wide which makes themunnecessarily thin compared to the ample progress markers. Moreover, the peach color ofthe vertical time line provides little contrast against the white background. Progress is not


Figure 3.52: Default progress line in Microsoft Project 2010, shown in red color.

showed when a task is ahead of schedule, only when it’s delayed, which makes Microsoft’sprogress line less useful for determining the general progress in a Gantt chart.

Comparing it to our progress line reveals an essential difference. As can be seen inFigure 3.53, our implementation focuses on showing the difference between the time line andthe progress line. Only when these lines are compared the overall progress can be estimatedat a glance. This effect is reinforced by use of red and blue color to further distinguishthe delayed tasks from those ahead of schedule. In Microsoft Project however, oversizedprogress markers steers focus towards the individual tasks, and the vaguely displayed timeline makes a comparison to the progress line difficult.

3.4 The Demonstrator

Based on the results from the research and idea generation phases, a concept demonstratorwas developed. Ideas were organized, merged and developed into a more tangible set ofinterface suggestions described in this section.

The final concept consists of a modular system with a streamlined interface that isoptimized for multiple screens. Much of the functionality is new and innovative, but theprocess views and overall appearance has been designed to resemble the user interfacesin common distributed control systems. Moreover, the concept is an integration of thescheduling part and the tracking part of the systems used today.

3.4.1 Process Overview

Today no information about the mining processes is visible for the operator above ground.The progress and status of the production has to be communicated through radio which is

3.4. The Demonstrator 41

Figure 3.53: Our progress line.

considered to be far from optimal. In our concept we use underground sensors to automat-ically receive updates about the current activities and their progress. This information ispresented to the mine operators in real time on a dedicated screen.

The image in in Figure 3.54 shows the process view. It contains a flowchart visualizationof the mining processes as found in a traditional process control system. This allows anoperator to control and supervise various aspects of the mining process.

The process view contains different process objects that symbolize production points,interim storages, crushers, hoists and conveyor belts. Connecting lines between the processobjects show the transportation paths of ore and defines the logical structure of the mine.Each process object has one or two attached progress bars. These are used to indicate thecurrent phase in the drill-and-blast cycle as well as the amount of ore left to process. Thebars are updated in real time.

The images in Figure 3.55 show the graphical objects that correspond to the differentprocesses in the mine. Descriptions, from left to right:

– Hoist - an elevator for crushed ore for moving it to ground level

– Production point - the places where ore is extracted

– Crusher - where the ore is crushed into smaller pieces for better handling later on

– Storage - pits used as interim storage space for the ore

– Conveyorbelt - for transportation of crushed ore

The process view is segmented into four parts, showing the three active levels in the minesurrounded by a dashed frame and, in the bottom right, the sub-processes above ground.


Figure 3.54: Process flow diagram of the mining processes

Figure 3.55: Process view objects

3.4.2 Process view layout

In existing distributed control systems, designing process control diagrams has to be per-formed manually. In the future, this will probably be done automatically using graph layoutalgorithms, but until then it will remain being a task performed by an engineer.

Three layout suggestions for the process view were created with the goal of maximizingthe utilization of available screen space while keeping logical structures such as levels in themine spatially grouped. The process diagram in Figure 3.56 was the first version. It wasadapted to fit a wide screen display, but did this unsuccessfully since the process objectsended up being too small.

A second version was created to make better use of the pixels. By rearranging androtating the objects, the second version was better with slightly bigger process icons, asshown in Figure 3.57. Here the mine levels are easily discerned, but there is still room forimprovements.

The third and final version shown in Figure 3.58 was considered to be the best. It containsmuch less white space than the the two previous attempts and it manages to provide a clearoverview with distinctive separation of the mine levels.

3.4.3 Ore tracking

Today there is no way of telling the origin of a specific ore sample. Being able to track thesource of a high quality sample could improve the upcoming production, something thatprobably will be possible in the future.

In the concept showed in Figure 3.59, visualization of the flow of ore has been incor-porated directly in the process view by varying the line thickness between two processesproportionally to the amount of ore that flows between them. This allows an operator to


Figure 3.56: First version of the process view

Figure 3.57: Second version of the process view


Figure 3.58: Third version of the process view

track an ore sample back to its source and show which production points are contributingthe most.

Figure 3.59: Material tracking in the process view

In all mines it is important to be able to separate different types of ore. Today thisis handled manually which occasionally leads to mix-ups, but it also put an unnecessaryworkload on responsible operators. Using the visualization in Figure 3.59, different kind ofore types can easily be distinguished using different colors on the lines.

3.4.4 Map view

The map view in Figure 3.60 is a two-dimensional geographical representation of all thelevels in the mine. Having quick access to a map could simplify the work for an operator inmany situations. Today the operators in the studied mine rely on physical maps that areplaced on a wall behind their desk. A map view that seamlessly integrates with other partsof their computer environment have many advantages. For example, thanks to the trackingsystem the operators could use the map to quickly locate and guide people in case of an


emergency.

Figure 3.60: The two-dimensional map view in the concept demonstrator

A map view can also be used to visualize the movement of smoke. Toxic gases andgas explosions are two significant dangers associated with underground mining today. Inthis concept, data from gas sensors is used to visualize the flow of toxic gases in real time.This allows the operator to monitor any smoke development in order to instruct and guidethe underground workers into safety. If the ventilation system is manually controlled, anoperator could also adjust the fans to improve the air flow.

The map view can be used to visualize the position and movement of many different kindsof resources including vehicles and people. This functionality is tightly integrated with theother views so that clicking an activity in the Gantt chart would show its geographicalposition in the map view.

3.4.5 Gantt view

Gantt charts are used for planning the production in the studied mine. However, in theircurrent system the operator is not able to view the status of an activity in real time. Delaysare often not reported in until after an activity ends which makes it harder to make effectivereschedules. From a usability perspective the existing Gantt chart is visually cluttered withexcess usage of color and text labels. These problems have been solved using a new activityblock visualization where the usage of colors has been minimized and the text labels havebeen replaced by icons.

This results in a cleaner Gantt chart and allows the use of color to be reserved to morecritical functions, such as alarms. Figure 3.61 shows the implementation in the conceptdemonstrator. The icons are visually distinctive and are probably easier to recognize thanthe text labels used currently. They also have the advantage of being language independent.

The activity boxes have a progress bar at the bottom that show live progress updatesusing sensor data from the underground machines performing the activities. This allows theoperator to response to delays and perform early reschedules.


Figure 3.61: Gantt view implemented in the concept demonstrator

Chapter 4

Discussion

To summarise, the conceptual demonstrator presented in this thesis implements a selectionof the ideas and concepts created in the idea-generation phase. It tries to solve many ofthe individual problems that were identified when analyzing role descriptions and materialfrom field studies that were performed in a swedish mine, but perhaps the most importantfeature of all is that the user interface gathers and visualizes the information needed by amine operator in a single place.

Visualizing information will become more and more important in the future. Automationtechnology will reduce the number of people needed to operate a mine, but also increasethe need of supervision. This explains why tracking of resources has been so central in thisthesis. Main results include three graphical views that allows an operator to track almost allaspects of the mining process - including a Gantt chart view for scheduling and tracking theprogress of activities, a Map view that allows an operator to see the geographical positionsof workers and machines, and a Process view to track the flow of ore from production pointsto the stockyard above ground.

The Gantt chart view is using icons to define the different types of mining activities.This was concidered to be a big improvement compared to the text labels found in theGantt chart currently used in the studied mine. Icons was found to reduce visual clutterwhile having the advantage of being language independent and easier to learn. The Mapview showing a 2D representation of the mine that consists of the individual levels that havebeen flattened out and positioned next to each other. A few other techniques for mapping3D data to a 2D space is discussed as well, but this solution was regarded as the best onebecause it preserves most of the significant geographical information needed by an operator.The Process view is using the width of the lines between processes to indicate the amountof ore that flows between them. This visualisation allows an operator to quickly assess thestatus and progress of the current production.

4.1 Reflections on the workprocess

This sections is meant to be a reflection of the work process of this thesis. Firstly, there willbe a description of what Human Computer Interaction is. Secondly, user centered design willbe described together with and how it is usually put through. Action research is describedas well. And lastly, there will be some reflections of the work process of this thesis and howsimilar processes could be handled by design engineer students in the future.

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48 Chapter 4. Discussion

4.1.1 Human Computer Interaction

Human Computer Interaction (HCI) is a research area that emerged in the early 1980s asa specialty area in computer science. It has since evolved rapidly into a multi-disciplinaryresearch area incorporating diverse concepts and approaches. Nowadays, HCI consists ofa range of fields of research and practice in human-centered information[3] with an aim atimproving user satisfaction by making systems more user-friendly. As HCI studies bothhuman and machine perspectives of interaction, it draws from supporting knowledge ofboth the human and machine sides - involving computer graphics, programming, cognitivescience, linguistics and human behavior etc[33].

Whether HCI is really needed or not, there are examples on how things have turned outto be disastrous due to badly implemented systems that totally disregarded HCI aspects.Such as, when a bus driver misinterpret the road sign indicating a closed road which wasconfounded with a sign indicating passenger vehicles, ending up in an accident causing sevendeaths[35].

4.1.2 User Centered Design

In order to develop usable products, it is quite obvious that users need to be involved fromthe beginning throughout the process, which is also the definition of a user-centric design(UCD). In broad terms, UCD is a process in which the needs, wants, and limitations of finalusers of a product are taken into consideration during every stage of the design process.

As a whole, UCD can be seen as a multi-stage problem solving process, beginning withdesigners trying to analyze and foresee how users are likely to use a product, propose solu-tions and later commit user tests with actual users in order to make additional iterationsof specific process cycles towards a finalized product. What it differs from other productdesign processes is that UCD attempts to optimize the product around how the users can,want, or need to use the product rather than making them adapting to a certain product.

4.1.3 Action Research

Action Research (AR) is an explicitly democratic, collaborative, and interdisciplinary re-search approach with two goals, to improve both the subject of the study (the stakeholders)and the academic goals of generating knowledge, achieving both at the same time[19]. Thefocus is set on creating research efforts ”with” people experiencing real problems and not”for”, ”about”, or ”focused on” them[11]. This is done by putting both the researchersand the stakeholders in the center of the process, and taking advantage of their valuableknowledge when dealing with an issue.

The process itself could be represented as a spiral with progressing circles of planning,action, and reflection - the goal being not to find the solution to given problems at once butto iteratively find solutions that are ”better” than the previous solutions.

4.1.4 Reflections

The way to work during this thesis has not been easy to comply with all the time. Therehave been many times that we have had difficulties with knowing what to do or how toperform a task.

Before the work could be initialized the thesis group used a period of approximately sixweeks to get a grip of the span of the project; which field the project was in, what wasactually the problem that needed to be solved, what the role of ABB was in the current

4.1. Reflections on the workprocess 49

situation, and even what our roles were in the project. This way we were able to narrowdown the whole to a more manageable entity, or at least we tried to do so.

But due to a limited project time span of about 3 months, consisting of a large amount ofdeliverables towards ABB (our stakeholders) which needed to be taken into consideration,some important stages of the design process had to be skipped, others be merged andstripped (Evaluation was skipped, Design and Development were merged into one stage).The focus was set on producing and delivering concepts as the main work, i.e. we had tojump directly to the Design/Development stage. This resulted in working with creativetechniques to come up with and refining new ideas and concentrating on how to implementthem; rather than firstly spending time on research through academic papers and traditionalliterature study to get a correct view of the nature of the problem and with that in mind tryto come up with solutions for the different problems met. This way to work was problematic,since the process was not like any other that we had worked by. Just by not conductingevaluation of the parts, we could not decide whether our decisions were feasible or not. Wehad to rely on our collective experience with every decision that had to be made. To add toit all, due to the limited project time we had not access to end-users - making the reliabilitytowards each others experience crucial. Worried thoughts about if we are on the right trackat all, or worrying about concentrating on details too much was something recurring duringthe project. Later on, we could back up this process with research and found that it couldbe defined as Action Research[11][19].

A reason that the project was felt messy and uncertain, that we very often were concernedabout the decisions taken and completed operations, or if the work could be supported byresearch at all, could be explained by how we as design students have traditionally beentaught to deal with HCI design projects. Since the main objective is new knowledge beinggained for students when conducting HCI projects during the period of studies, a normativeprocess (as described in the paragraph below) is traditionally being taught when dealingwith HCI design projects. The product itself is rather used as the means.

Human Computer Interaction (HCI) design methods, such as the User Centered Design(UCD) which we originally thought would best be applicable to our situation, are commonlydepicted as a cyclical process of analysis, design, development, and evaluation. Usually it is alinear process with the four parts seen as essential stages, each stage being iterative[11][16].It is a traditional normative process[16] and could be accounted to as being a process-oriented conservative approach in HCI. Meaning, there is a defined problem specificationto be solved and by following the stages in detail, according to structured steps describinghow to deal with a situation and in what order, solutions would be found that comply withdifferent constraints of the project. Such as time, cost, etc[4][21]. In conclusion, the designengineers are perceived as researchers.On the contrary, design engineers involved in HCI projects in the industry are usually in-volved personally in the projects and are perceived more or less as ’creative geniuses’[4]. Aprecisely defined problem is not really available in the beginning, resulting in the focus beingmore on the creativity of the designers rather than methodology and research. Thus, manyideas and concepts are created in parallel and counted as the outcome. Research is moreor less a tool used to back up the results in retrospect[4][21][5]. Instead of using UCD, amore appropriate method to use in this case is Activity Centered Design (ACD). In contrastto UCD, ACD is a method originating from activity theory focused on the activities to beperformed when using the desired product rather than on the users of the product. Thus,products developed this way could be used during an extended period of time and not onlydepending on a specific situation[28].

50 Chapter 4. Discussion

To summarize, as a student one has knowledge of only one approach to design in HCIand when getting to work one often encounters a different view of design in HCI, resultingin major complications in the work - difficulties to get started with projects, not reallyknowing what to do and/or how to do it. The student has to cautiously thrive forward andput trust in the outcome being feasible, no matter what. Thus, it conflicts the way of workone has been trained to follow.

In order to facilitate for future students and help them avoid the trouble we have faced,a compromise is needed. Schools and universities have an important part to play here. Bymaking a change in the teaching approach, students would be prepared to face challengesin the best ways. As a bonus, the university in question would be better recognized amongthe industry and the academia[6][2]. A suggested solution could be to not only rely on oneapproach in HCI design but to emphasize other approaches in addition to the traditionalnormative process.

Chapter 5

Conclusions

A graphical user interface solution has been created that gives the mine operator in anunderground mine an improved overview of the physical mine, its production and involvedresources. Since this undertaking represents the bleeding edge technology in this field, theamount of publicly available research was found to be negligible. Presumably, most of thebig mining companies are performing similar work, but not readily publishing their resultsbecause of patents and the financial potential of the research. This has limited the workdone in this thesis, but also provided an opportunity for innovation.

Most of the ideas and visualizations have deliberately been left at a conceptual leveland need to be developed, evaluated and refined before considering using them in a realapplication. Being conceptual and spanning a wide range of topics, the results shouldpreferably be used as a basis for discussion and future research in the area of process controlsystems for the mining industry. Some of the results, such as those concerning Gantt charts,are more general in nature and could be applicable to other fields of research as well.

Increasing the amount of transparency in an underground mine also introduces a wholenew set of privacy issues. In a future mine where sensors are ubiquitous and the operator isable to track the position of everyone and everything in real time, these issues will becomeeven more pressing, and solving this without compromising security is an important researcharea that could greatly impact future development of process control systems.

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52 Chapter 5. Conclusions

Chapter 6

Acknowledgements

We would like to thank the following people:

Costudent Diamond Dong for doing this thesis work with usSupervisor Christine Mikkelsen at ABB for her support and encouragementSupervisor Helena Lindgren at Umea University for her support and patienceCoworker Isak Savo at ABB for his open-minded attitude towards designers

Filip wants to especially thank his wife Linda Lundeholm for enduring their first fivemonths of marriage which were spent living apart because of this thesis work.

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54 Chapter 6. Acknowledgements

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