Human Factors in System Design: Train Ticket Vending Machine Report

This report delves into the human factors involved in the design and usability of an automatic train ticket vending machine. It begins with an introduction to interactive systems and their importance, followed by a description of the specific system, its users, and their capabilities. The report outlines use cases, detailing aspects of system usage and providing descriptions of these cases. The evaluation methodology section discusses the evaluation procedure, user tasks, and debriefing procedures. The evaluation section presents performance and results, including a presentation of findings. The report then summarizes the evaluation results, assesses usability, provides a critical appraisal, and concludes with recommendations for improvement. The report emphasizes the importance of user-friendly interfaces and addresses usability issues such as ticket refunds and the overall ticket-buying experience. The analysis covers various aspects of the ticket vending machine, including the interface, payment methods, and user interactions. The report also highlights the use of heuristic evaluation to identify potential problems and improve the overall user experience.

Running head: HUMAN FACTORS IN SYSTEM DESIGN
Interactive System: Automatic Train Ticket Vending Machine
Name of Student-
Name of University-
Author’s Note-

1HUMAN FACTORS IN SYSTEM DESIGN
Table of Contents
Introduction......................................................................................................................................3
Part ONE: Interactive System and its Users....................................................................................4
Description of Interactive System...............................................................................................4
Description of User Populations..................................................................................................4
Assumptions about Capabilities of Users....................................................................................5
Part TWO: Use Cases......................................................................................................................6
Aspects of using the system.........................................................................................................6
Descriptions of the use cases.......................................................................................................6
Part THREE: Evaluation Methodology...........................................................................................8
Evaluation Procedure...................................................................................................................8
User Tasks...................................................................................................................................9
Debriefing Procedure...................................................................................................................9
Part FOUR: Evaluation..................................................................................................................11
Evaluation Performance.............................................................................................................11
Evaluation Results.....................................................................................................................13
Presentation................................................................................................................................14
Part FIVE: Findings of Evaluation................................................................................................18
Summary of Evaluation Results................................................................................................18
Assessment of Usability............................................................................................................19

2HUMAN FACTORS IN SYSTEM DESIGN
Critical Appraisal.......................................................................................................................19
Conclusion.....................................................................................................................................21
Bibliography..................................................................................................................................23

3HUMAN FACTORS IN SYSTEM DESIGN
Introduction
An interactive system is a system which takes input from the user and performed the
user-desired operation. Interactive systems are elementary to use. An end user can perform
required task easily to get their job done. Interactive systems have an attractive interface it guides
the user and gives directions to operate the system. Interactive system allows user interaction.
Interactive systems are computer systems characterized by adequate amounts of communication
between human and the computer. In olden days Interactive systems are command based, and
these are not user-friendly for some users feel difficulty to use these systems. Nowadays all the
systems are, and user interface based systems. Most of these are developed based on Windows or
Linux based systems.
Interactive systems are classified as per their user interaction.
1. Command based systems
2. Menu based systems
3. User interface systems
Usability evaluates interactive systems. Usability engineering is a methodology to assess
applications which include users, contributors, and developers. This report contains usability
issues of existing automatic train ticket vending machine. To analyze the usability of existing
train ticket vending machine considers user requirement and operations performed by the user.
To identify usability issues case studies are helpful.
In our report consider automatic train ticket vending machine (TVM), the general
purpose of this machine vending a train ticket to the user. Ticket vending machine is automated

4HUMAN FACTORS IN SYSTEM DESIGN
and functional with human interaction. The vending machine produces train tickets by taking
cash from the user. Ticket vending machine dispenses the tickets upon the user input. The
dealings consist of user exploitation the show interface to pick the destination and range of
passengers and kind of journey. The interface is user-friendly and provides an excellent user
experience.
Part ONE: Interactive System and its Users
Description of Interactive System: Ticket vending machine sells ticket upon the received
request from the user. The vending machine contains an interface which is good to use and create
a user-friendly experience. A user first selects the desired option from the given appeared
MENU. The MENU comprises different options, and each is used for some specific operation.
The menu contains enquiry, availability of tickets for reservation, purchase of tickets. So the user
may select any of these options/choices and follow the instructions of the vending machine. The
primary job of the device is vending tickets to the user or selling tickets to the user. To perform
this task user select the option of “Purchase ticket” from the MENU. In the next screen enters the
destination and source address in the respective fields and enter passenger number (how many
persons to be travelled) then proceed to check out and pay the money via bank credit or debit
card or pay cash by cash deposit machine which is available in the vending machine. Here the
user may have the problem because the user may not sufficient money or change to pay if the
user spends more than the cost how the user gets back the excess amount and if the user wants to
cancel the ticket how the user gets the cash back. These are usability issues in the existing
system.
Description of User Populations: This interactive system can be used by all the users
who want to purchase ticket online. This interactive system helps the users to buy train tickets by

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searching their trains. The target users of this interactive system is the users who want to buy
tickets from the automatics ticket vending machine.
Assumptions about Capabilities of Users: There are four assumptions that can be stated
about the capabilities of the users. The first assumption states that the usability is a basic
property for building of interactive digital technology. The second assumption states that
methods that are assumed are prepared by professionals of Interactive design and Human
Computer Interaction who will help to determine the usability of the system. The third
assumptions states that system that is designed is usable to all the users. The methods states
about how the interface is usable. The fourth assumption states that all the methods that are used
for this interface are all documented.

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Figure 1: Overview of the System
(Source: Created by Author)
Part TWO: Use Cases
Aspects of using the system: The aspects that are needed for using the system is
acceptance aspect which states that the application is accepted by all the users. The application
acceptance aspect involves technology enhanced learning and the usage of learning. Business
aspect is also stated in this while using the system of automatic vending machine. The business
aspects states holistic effectiveness as well as efficiency of the technology that is designed. The
benefits and the value of the technology and the difficulty is considered in the business aspect.
There is also instruction aspect which states that proper instruction should be provided to the
user who will use the interactive system.
Descriptions of the use cases:
 A ticket vending machine produces the ticket to the user/passenger. Generating train
tickets is the job of this vending machine. Here user or passenger is the actor. Ticket
vending machine is a combination of both hardware and software. The evaluation that is
done in this research paper is heuristic evaluation which states all the methods that are
used for building the user interface. The problems that are associated with this design is
that this ticket vending machine needs to have an attractive interface so that the user finds
the interactive system attractive to use. The vending machine instructs the user what to do
next, but there is no such written manual instruction for the users where users can check
the instructions. This is another disadvantage of using this automatic ticket vending
machine.

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 A user may do any of the operations such as searching for trains, purchase the tickets as
well as generate train ticket from the vending machine. The above diagram depicts the
use case diagram for the automatic train ticket vending machine. For purchasing a train
ticket, the user will have to give the correct input like destinations and source stations and
the total number of passengers so that the machine will calculate the price for all the
passengers and print a ticket to the user after payment of the transaction is successful.
Bank credit or debit cards are used to pay the price for tickets or by cash also pay and
collect the change from that machine. The biggest challenge faced by the user is
collecting change from the vending machine. The TVM train ticket vending machine is
working with user interaction.

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Figure 2: Use Case of Ticket Vending Machine
(Source: Created by Author)
Admin can perform only operations managing and monitoring the whole system.
The ticket vending machine also has a technician who look after the information system
of the ticket machine. He looks after if any part pf the system is not working. The technician also
looks after the printing system of ticket whether there is paper present in the system or not.
Ticket merchandising machines (TVMs) ought to give passengers with the chance to
create fast and straightforward rail price ticket purchases at stations. There are concerns that the
quality of information provided to passengers using TVMs is insufficient to enable them to make
purchasing decisions appropriate to their journey needs. The use case diagram of the automated
ticket vending machine is shown above.
Part THREE: Evaluation Methodology
Evaluation Procedure: There are mainly three evaluation procedure that can be stated for
evaluation. There is Heuristic Evaluation, Think Aloud Evaluation, and Pluralistic Evaluation.
For carrying out this research study, Heuristic evaluation is carried out in which the research
goes through different scenarios and tries to find out the errors that are based on the rule of
Heuristic Evaluation. The rules that are involved in Heuristic Evaluation is visibility of the
system status. In Heuristic Evaluation, it is also searched that the system that is designed matches
between the system and the real world. Heuristic Evaluation should also have user control and
have freedom for accessing the system. The errors that are found in the system should have the
prevention methods where the system is capable of handling all the errors involved in the
application. There should be flexibility and there should be efficiency for using the application.

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The Heuristic Evaluation helps the user to recognize, recover as well as diagnose the functions
that are involved in the system and there should be involvement of undo function that can help
the users from making an error while inputting or performing the tasks. A last the Heuristic
evaluation should involve a documentation where all the methods and steps are clearly
mentioned related to the automatic ticket machine that is designed.
User Tasks: User Task is basically used for model work that are needed to be done by the
humans. When a particular process execution arrives in a User task, then a new task is created in
the list of user that is assigned to the task. Each task involved in the system application indicates
due date of the task. All the due dates of the task should be followed. The tasks that are involved
in the application system should be up to date. The initial date of the follow-up is to be created in
the user tasks. The user task is used by a single user or can be assigned to a list of users or list of
groups for using the automatic application software.
Debriefing Procedure:
 The main aspect of the machine is the Home page of the screen. It contains all the
functions and instructions that the user can see. This evaluation is based on the ticket
vending machine. In different countries, there are different vending systems. The options
and the pattern on the screen changes with different vending machines. As the languages
in different countries are different, so the options on the system also change accordingly.
The machines entry screen has different languages like local language and English
language. The user needs to select their desired language he/she prefers and proceed to
the next steps of searching trains, checking availability, booking tickets as well as
generating the tickets.

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The issues of the users are to be considered in evaluating the ticket vending machine.
There are many issues that the current vending machine offers. For mitigating the
problems in the existing vending machine, the interface of the new ticket vending
machine is evaluated so that there are no such issues faced by the user. So the problems
that are met by the user are given below
1. Ticket refund
2. Ticket buying facility
These are the issues faced by the user while buying a ticket.
The machine used for vending automated electronic tickets helps to generate the ticket
for train and supports all kinds of payment that the client is comfortable with. If the user
makes more payment than the amount of tickets, then the changing amount is returned to
the users in the cash dispenser. The extra amount of change comes in the cash dispenser
by the system. The machine is capable to take the currency of countries and accepts
denominations of all the types including the coins also. Means the machine should work
like cash deposit machine so that the end user can get the money if they pay an excess
amount on the ticket cost. Some railways also offers some discount on some tickets, as
well as discounts on senior citizen people. So, the machine considers all such cases while
printing the ticket and calculate the price accordingly. After successfully printing the
ticket the machine says happy journey to the user by showing a message on the screen.
The ticket also has written happy journey on it.
 By observing the design and functionality of the train ticket vending machine, the first
screen of the machine contains basic operations which are performed by the user. So, the
user may perform all the operations easily. Bullet points for every choice permit the user

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to drill-down into individual classes if needed. Additionally, the user who has a railway
card can insert the card in the card reader of the machine. Having a railway help the user
to get a high amount of discount for the railway tickets and sometimes can avail them as
free also.
Selecting destination and source stations of the user is typical when the user unable to
find the particular station. The station selecting screen provides facility to the user. As
the screen is sensor touched, so the user can drag the pointer on the map to choose the
particular place if the name of the station is not available in the list. This makes the
system more user-friendly and efficient in its work. If the user inputs any letter wrong
accidentally, then the suggestion of the correct word is shown by the machine. This is
visually emphasized by changing their colour and shading so that they no longer invoke
the affordance of pressing. The main aim behind this approach is that invalid inputs are
prevented and complexity is reduced as users only need to consider a subset of control
elements/input. This may be particularly useful in the case where the user is not entirely
sure about the spelling of a start or destination.
So finally confirm the destination and source stations, concession details and include
passenger details and calculate the price and print the ticket.
Part FOUR: Evaluation
Evaluation Performance: This methodology is mainly evaluated to get the interface of
the ticket vending machine. Evaluating an interface means whether the system is perfect for the
user to use. There are many factors that the evaluation methodology of an interface deals with.

12HUMAN FACTORS IN SYSTEM DESIGN
The user using the system is to be satisfied while using the system. The system should work
properly and there should be no error in the system. The evaluation study involves usability
testing, expert reviews, the instruments that are needed to do the testing, and whether the system
is accepted by the user or not. All these factors are explained in the next section of this report.
The usability methodology mainly has three main factors like efficiency, satisfaction and
effectiveness. The evolution methodology is a usability methodology. In this section, a detailed
evaluation methodology of the ticket vending machine is described briefly. As per the evaluation
methodology, the primary factor is efficiency. An efficient vending machine produces accurate
results upon the user request and entered input by the user.
The interface of the machine should play the primary role in automated ticket vending
system. The interface is containing menu options which are possible to perform by the user.
When the interface works correctly, the system functionality also is accurate and gives accurate
results to the user. Machine selling tickets to the user when the user enters valid input in the
respective fields are source and destination stations. Then the user makes a payment for the ticket
by using the available payment methods like debit card/credit card or by cash. While paying for
the ticket in cash, the user will have to insert exact amount of money; otherwise, the machine
should give the change to the user. Exact change is one of the main problems in the existing
system of the ticket vending machine. Also, cancellation of ticket and payment reversal is a big
task in these current systems. Railway boards decide to develop accurate dispense of the cash by
cash dispense in the existing machine.
In existing machines, before generating the ticket, the user has to pay the exact amount of
money in the cash dispenser of the vending machine. The system cannot return the change, and
in that case, the user needs to cancel the ticket/journey. To overcome this issue, the new interface

13HUMAN FACTORS IN SYSTEM DESIGN
of these machines is designed that will be able to give change to the user. So the future systems
will not have the drawbacks of not giving change to the user.
In the evaluation methodology, the second factor is related to satisfaction. Satisfaction
depends on user experience. If the user is not comfortable with the system, then the system is not
efficient and need to change. System designing depends on the requirements of the user only. If
the ticket vending system fulfils all the requirements of the user, then the system functionality is
satisfied to the user. If the user purchases ticket he/she doesn’t have sufficient money he/she paid
more than the price and the remaining will be paid back to the user. In this case, the user will be
satisfied because of the functioning of the system. So the future system is fulfilling all the user
requirements.
The third factor is effectiveness; effective system effectiveness depends on the system
designing and development. When the user has good user experience while using the system,
then the system is considered as an effective system. When a system works correctly, then it
means that the design is perfect. When the system gives accurate results to the user, then the
system is mainly depended on the development and resource gathering of the data in the ticket
vending system.
Evaluation Results: Usability study involves both ends user; the admin and the user.
Usability mainly defines the possible operations done by user and admin and if they are facing
any problem while using the system. In usability phase, mainly the operations of the phase are
defined by the developers. Before developing any system, developers take the requirements of
the users and develops the system according to that.

14HUMAN FACTORS IN SYSTEM DESIGN
Usability testing involves checking the system that has already been developed before
using the system by the public. The system should be efficient enough to fulfil all the
requirements of the user. Once the system is made live, it is very difficult to alter the function of
the system. So, before making the proposed automated ticket vending machine live to the user, it
has to be checked whether everything works well in the system. All the parameters and other
resources are collected and test in different possible scenarios. So that the usability testing is
essential for developing an interactive system.
Presentation:
 The vending machines that are used for ticket generating are mostly screen touched. Most
vending machines are touch screen machines. A user uses these machines by sensitive
finger touch. After selecting the language, a user enters into the next screen that is menu
screen.
Menu screen as like below.
User goes with the desired selection of the menu. The user needs to select the option that
he/she wants to select. In the ticket vending machines next screen firstly offers the most
common destinations which are very popular. Or there is also an option of fetching the
map from where the user can select the source and destination where he/she wants to
travel. Selecting the place is a concession to the usability principle of potency. The
destination stations are listed in the system in chronological order, and the selected
options are save for other travel options. The labels on these price tag choices are shorted
for the sake of fitting into the allotted space associated there's most undoubtedly an
assumption of data derived from previous expertise. If the user doesn’t find the

15HUMAN FACTORS IN SYSTEM DESIGN
destination station in the appeared list of the screen the user can select the place by
clicking on the map option. The user will have to choose the location where he wants to
go. The vending machine also facilitates to view the list of stations between the source
station and destination station or the nearby station of the place entered. So the user can
quickly identify the stations if the user doesn’t know where to get down from the train.
Go deeply into the evaluation of the ticket vending machine, if the user wants to travel to
London, then he/she must choose the purchase ticket option from the Menu.
Then the next screen appears as a list of stations which are popular and then select the
station from the list of the stations. So London station is selected by the user from the list.
After choosing the station, the total number of passengers are to be entered who will
travel, pay the money and finally print the train ticket. There is a separate place for
selecting the number of passengers specifying adults and children. Once the selection of
station and passenger list is entered, the total price is calculated by the machine
automatically. The user selects the payment option by which he wants to make the
payment. There is basically two option for making the payment. Either amount is paid by
cash or credit card payment or by net banking.
Once the payment is successful, the ticket is printed and comes out. Payment made by
different options by the user. If the user selects payment through internet banking or
online banking mode, it will redirect to the next screen of that particular bank where the
user has an account. In that screen, the user makes the payment by his/her banking
credentials. The same procedure is also followed while making the payment through
credit card. Only the different thing that is to be selected is the option of paying. The

16HUMAN FACTORS IN SYSTEM DESIGN
options that are showed in that list comprises of debit card payment, credit card payment,
or by cash.
If the user uses the service of paying the amount by cash, the user can put the exact fare
in the cash dispenser or can put any amount of money if the user does not have that
particular exact cash that is to be paid. The machine is developed mainly to overcome
the problem of paying the exact amount of money in the cash dispenser of the machine.
 The testing results are shown below of the user design interface.

17HUMAN FACTORS IN SYSTEM DESIGN

18HUMAN FACTORS IN SYSTEM DESIGN
Part FIVE: Findings of Evaluation
Summary of Evaluation Results: When the user confirms the details of the passengers
and after all the procedure of payment is complete, a printed ticket for travelling is generated by
the machine. The vending machine prints the ticket only after confirming the details of the user.
The ticket vending machine is reliable and comprehensive. To make the system successful, there
should be a good communication in between the vending machine and the user. The

19HUMAN FACTORS IN SYSTEM DESIGN
communication should be done properly in between the system and the user. It works with an
interaction of the human and based on the input given by the user.
Most of the railways using the automatic train ticket vending machines at the stations
helps to reduce the complexity of vending tickets standing in line at the ticket counter and
therefore, simplifies the system of selling of tickets. All over the world, railways used ticket
vending machines. Some countries even issue railway cards. The railway cards help the user to
get more discounts on the tickets, passenger seasonal tickets and concession tickets these all
options are acceptable by the ticket vending machine. So many railways are introducing the
machines that are user-friendly. The machines for vending tickets are so much easy and user-
friendly that they can be used by the blind people as well. Ticket vending machines are based on
technology working machines. In some of the countries, there are also machines that connect
with the user over voice conversation. Designed machines with voice interaction mean that the
machine can take the instruction from the user over voice as input and the machine can validate
it by performing such actions. These type of machines are very helpful to blind people as well, so
that blind people can also purchase tickets or utilize the service of the automated ticket vending
machine that is offered by the ticket vending machine. Vending machines give high quality
services to the user.
Assessment of Usability: The application that is designed have helped the people to learn
about the design the application. The design application helps all the users to use the machine
efficiently. Task analysis of the application states about how the users uses the application and
also contains all the steps about what the people needs to do to for using the application. All the
problems that are related with the application are stated as Heuristic evaluation. The heuristic
evaluation is done from the human computer interaction.

20HUMAN FACTORS IN SYSTEM DESIGN
Critical Appraisal:
 The machines for automated ticket vending is very different from the counter ticket
vending. The ticket vending machine works for 24 hours a day and 365 days in a year.
This helps the user to avail service from the railway at any time they want to. The
services of the system can be utilzed by the citizens who frequently travel on the train.
The systems of the automated ticket vending machines are based on Linux. Technicians
or software engineers troubleshoot the machine if the machine is not working properly.
These machines are touch screen calibrating and voice-based interactive machines. High
end scalable and secure machines. It works in any kind of general environment or
weather conditions. It has access to all the railway stations across the country. Some
countries design their machines support multiple languages to ease of the usage for the
local people. Because local people know only local languages, the railways thought of
that matter and introduced multi-language supported machines. In India, these machines
issuing platform tickets also, and officials of Indian railway board believe that it reduces
the burden on the ticket counters and as well as reduce the complexity of the work and
manpower. Vending machines are performed the user required action in a fraction of
seconds with accurate results, so the passengers and people are interested in using the
machines. By attracting the people railways earning more money than the usual
 The below stated are the findings of the evaluation of the automatic train ticket vending
machine. Steps for designing a user-friendly train ticket vending machine.
1. A user selects the language in the entry screen of the ticket vending machine.
2. After selecting the user found services or basic operations which are
performed by the user.

21HUMAN FACTORS IN SYSTEM DESIGN
3. User goes with any of the available operations and follows the guidelines of
the machine.
4. User select purchase ticket option if the user wants to buy the ticket.
5. User select availability option if the user wants to check the availability of the
trains.
6. In the new vending machines make video or user guide to the user to perform
the operations.
7. A user may enter input manually for the selecting source and destination
stations.
8. User select stations from the appeared list of stations also.
9. The machine should also accept railway concession cards or eligibility cards
etc.
10. A machine should accept cash and as well as dispense cash if the user paid
excess amount than the price of the ticket.
11. A user may pay the price to the ticket by online pay or credit or debit card the
machine should support this functionality.
12. Provide the ticket cancellation facility to the user and at the same time, the
amount is transferred or refund to the user so the machine should work like
cash dispense machine.
13. To print the ticket the machine asks for confirmation.
14. The machine should have capable to guide the handicapped persons like blind
and deaf people also.
15. The machines front screen should be user-friendly.

22HUMAN FACTORS IN SYSTEM DESIGN
16. Each and every step in developing the machine should be, and the user
doesn’t feel difficulty while using the machine.
Conclusion
From the above discussion, it can be concluded that an automated ticket vending machine
is very much useful for the user who travel by train frequently. The ticket vending machines are
basically screen touched that are operated by Smart cards most of the time. The passengers can
avail the tickets from the machines at all time he wants to. The system gives service for all 24
hours in a day and for all days in a year. The train ticket vending machine is an example of
interactive machine.
The main purpose of developing the machine is generated or print train ticket
automatically by the user. The drawback that the current system avail is that the payment is to be
made only with the exact amount of fare for purchasing the ticket. To mitigate this drawback
basically, this system is proposed. This proposed system of the Automatic Ticket Vending
Machine mitigates the drawback of the current systems. This is the common issue that is faced
by the user while fetching the ticket. When the user enter the input like source and destination
stations and pay the ticket. This proposed machine is expected to overcome all the present issues
of the Automatic Ticket Vending Machine.

23HUMAN FACTORS IN SYSTEM DESIGN
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24HUMAN FACTORS IN SYSTEM DESIGN
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