INTERNATIONAL JOURNAL OF LATEST TECHNOLOGY IN ENGINEERING,
MANAGEMENT & APPLIED SCIENCE (IJLTEMAS)
ISSN 2278-2540 | DOI: 10.51583/IJLTEMAS | Volume XIII, Issue VII, July 2024
www.ijltemas.in Page 181
Optimizing User Interaction and Notification Efficiency in Smart
Coin-Operated Printing Kiosk with Real-Time SMS Notifications
and Interactive Features
Geneveve C. Falcon
1
, Rosemarie Y. Saligue
2
, Emannuel T. Saligue
3
1
Department of Education, Division of Southern Leyte, Sogod, Southern Leyte, Philippines
2
Faculty of Computer Studies and Information Technology, Southern Leyte State University-San Juan Campus, San
Juan, Southern Leyte, Philippines
3
Faculty of Computer Studies and Information Technology, Southern Leyte State University – San Juan Campus, San
Juan, Southern Leyte, Philippines
DOI: https://doi.org/10.51583/IJLTEMAS.2024.130722
Received: 27 July 2024; Revised: 06 August 2024; Accepted: 08 August 2024; Published: 20 August 2024
Abstract: This study aims at designing and implementing a prototype coin-operated printing kiosk that will be able to run on
an SMS notification system and GSM technology in error management and user interaction monitoring. The prototype kiosk
was tested using a prototyping design with real customers to gauge accuracy, effectiveness, and learnability metrics. Data
collection was done using a modified Prototype Demo Form and questionnaires based on Whiteside, Bennett, and
Holtzzblatt's and ISO 9241 usability metrics. Results showed that the kiosk efficiently completes printing tasks and
documents copies are well accounted for, and that the kiosk is user-friendly. The findings were that the kiosk offers realistic
and convenient printing services within the school campus, therefore cutting down the number of times students need to leave
campus over their printing needs.
Keywords: Interactive Features, Printing Kiosk, Real-Time SMS Notification, GSM Device, Arduino Microcontroller
I. Introduction
Technological innovation has become essential in today's world, primarily aimed at enhancing community life. In this line,
present research into IoT in both academic and industrial sectors have focused on system architecture, communication
protocols, and sensor networks, with security and privacy protection taken into consideration, and many applications are
involved [1]. Among the numerous innovations jump-started by this technological evolution are smart coin-operated printing
kiosks. This new technology in kiosks embeds a number of advanced features to increase user convenience and operation
efficiency. Against the traditional vending machine, there are major improvements in terms of offering real-time
communication and interactivity to make user interactions easier.
These kiosks offer convenient on-the-go printing solutions, but their effectiveness relies significantly on optimizing both user
interaction and notification efficiency [2].
The modern student in school now greatly depends on technology to help the student complete tasks that include the printing
of various assignments, projects, and other important documents. The need for students to conveniently and prudently print
led to the initiation of the smart coin-operated printing kiosks, which enhance its advanced features to fit the needs of a
modern student.
Further, these smart kiosks far outperform the traditional printing methods with the aid of features such as real-time SMS
notifications and responsiveness in improving the overall user experience. The addition of real-time SMS notifications
against system status and user activities through GSM makes this very significant to smart kiosks. This improves not only the
user experience with timely feedback and error alerts to users, but also the operational management of the kiosks by means of
proactive error resolution and system maintenance.
These innovations have also been accompanied by challenges related to the optimization of user interaction and notification
efficiency. Real-time notifications in a user-friendly interface should be duly balanced. Efficient interaction design allows for
ease of use, while an efficient notification system will alert on time, always having relevant content without overwhelming
the user.
The challenges to be addressed in this work pertain to the optimization of real-time SMS notifications and interactivity within
a smart coin-operated printing kiosk. This piece of research evaluates the kiosk's performance on the bases of user interaction,
notification efficiency, and general effectiveness in establishing insights on how to improve both user experience and
operational efficiency for such systems. The findings in this study are expected to have an impact on the further development
of more intuitive and responsive smart kiosks and hence their utility in various settings and users' satisfaction.
INTERNATIONAL JOURNAL OF LATEST TECHNOLOGY IN ENGINEERING,
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ISSN 2278-2540 | DOI: 10.51583/IJLTEMAS | Volume XIII, Issue VII, July 2024
www.ijltemas.in Page 182
Research Objectives
The main objective of this study was to develop and implement a coin-operated printing kiosk designed to provide practical
and convenient printing services. Specifically, it aimed to:
1. Design and develop a prototype of an interactive coin-operated printing kiosk with an integrated SMS notification
system.
2. Estimate the effectiveness of the GSM device as an interface for handling system errors at the printing kiosk.
3. Express the level of user interaction provided by the printing kiosk concerning each of the following:
a. Accuracy: Print Job Accuracy and Error Management.
b. Effectiveness: It is the overall functionality and performance concerning the fulfilment of user needs.
c. Learnability: How easily a user can understand the kiosk and the tasks associated.
II. Literature Review
Digital printing technologies use bitmap images or patterns created by a computer to jet ink onto substrates. Over the years,
they have been predominantly employed for printing graphics and documents. Recent development efforts are focused on
production printing, with methods such as low-cost and high-frequency jetting, and high-resolution techniques. In addition,
intensive research has been underway to try and use digital printing for directly depositing functional materials. The reason
may be due to direct printing that offers advantages over conventional photolithographic methods and mainly reduces the
manufacturing costs since it is capable of additive manufacturing [12]. Automation's primary advantage is its ability to
enhance efficiency, simplify management, and enable multitasking across various contexts. This prototype offers a solution
for paper retailers and printing/photocopy shop centers at the University of Science and Technology of Southern Philippines,
catering to students who use bond papers, newsprints, and yellow papers for exams and other purposes. The vending machine
features a coin-slot mechanism and will automatically dispense the selected type of paper based on the amount of money
inserted by the student [13]. Traditional unmanned vending machines cannot bargain over prices and, simultaneously, cannot
provide personalized bargaining services [3]. Smart vending machines, as essential tools in the domain of unstaffed document
printing, will become prominent [4].
Vending machines are some of the machines in public places that dispense or vend products, including snacks, drinks,
newspapers, tickets, and cigarettes. According to these recent evolutions, they require control systems that have different
products of varying nature. According to Yang and Zhu, 2014 [6], a vending machine is an automated business device that
does not require help from a person; hence, it enjoys flexible operation hours.
While vending machines are more prevalent in private schools than public ones, the school stores a very common in both [7].
The internet is acting as a catalyst in these technological advancements and is therefore affecting most markets, including the
vending markets. The latest models of vending machines provide services such as mobile phone charging, offering free Wi-
Fi, and USB drive printouts [5]. These machines use several communication standards, and GSM is used for tracking sales,
users and machine operations, and sending multi-media messages [8].
It may further be capable of monitoring the availability of products and the health of the entire machine, thus keeping the
owner or user informed. Some recent trends in vending machines are high-definition touchscreens, cashless payment,
integration into IoT devices, and cloud services. A typical automatic selling machine is controlled by a Vending Machine
Controller, which normally controls all the basic tasks of an automatic selling machine, such as processing money and
managing refrigeration, lighting, and product dispensers [5].
The different elements of the vending machine communication system integrate to give a perfect experience to users. The
touch screen serves as an interface for multimedia, control, and communication. A standalone connection powers real-time,
two-way communication between the machine and users [8]. Data storage and processing servers tabulate statistical data for
easy management and stocking of vending machines. This brings a complete solution to the consumer's demand by enhancing
system efficiency [9].
III. Methodology
This study will follow the interaction design process which consists of 5 stages. The first stage was the establishment of the
requirements through interviews with the students, checking their work documents, and observation of them while interacting
with each other. Second stage was the analysis, which comprised the organization of the results from the observation to stress
the major issues to be addressed within the design phase. Third stage was the design phase itself where the requirements are
translated into detailed programs following the principles and rules of design, taking into consideration the different types of
users, all in an effort to ensure easy interaction and navigation.
In the fourth stage, a prototype of the coin-operated printing kiosk was developed and tested for evaluation. This was in
respect to the assessment of the prototype's design, functionality, and improvement segments by real-user testing. The
analysis of feedback was done in view of verifying the effectiveness, accuracy, and usability of the design. The study used
criteria from Whiteside, Bennett, and Holtzblatt, 1998; and the Prototype Demo Form from the Rochester Institute of
Technology. The results were used to base further improvements of the architecture and the design of the kiosk with respect
to accuracy, effectiveness, and learnability issues resulting from user evaluations.
INTERNATIONAL JOURNAL OF LATEST TECHNOLOGY IN ENGINEERING,
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The last stage was the implementation of the final design incorporating all necessary adjustments and enhancements.
Figure 1 Interaction Design Process of the study.
A. Research Design
This study fell under a developmental research design, which Richey defined as a systematic approach to designing,
developing, and evaluating instructional programs, processes, and products to ensure criteria for internal consistency and
effectiveness in 1994. In adherence to this approach, this researcher has designed, developed, and implemented an interactive
coin-operated printing kiosk. Testing of the kiosk was done early in its lifecycle with real users for assessing the accuracy,
effectiveness, learnability, and user experience. This research design has also allowed the researcher to collect data for
refining the design of the kiosk and its processes by focusing on the critical interface elements of the printing kiosk.
B. Research Environment
This research was conducted at Sogod National High School in Sogod, Southern Leyte. Being the only mega-secondary
school in the Division of Southern Leyte and being one of the bigger schools in Region VIII, it caters to a student population
of 4,005 served by 126 teaching staff. Because of its large potential user base, the prototype of the coin-operated printing
kiosk was pilot-tested in this location. These are the SPA, SPS, STEM, and the regular and senior high school classes. Where
in kiosks can be likewise deployed in other high-volume areas such as businesses or offices where printing is a regular need.
C. Research Respondents and Sampling Procedure
The respondents of the study consisted of the faculty, staff, and students of Sogod National High School. This sample size
was then proportionally allocated in every group using Slovin's formula, with a margin of error of ±0.05, as shown below:
where n = sample size
N = population size
e = margin of error (0.05)
Table 1. Distribution of Respondents
Respondents
Population Size
Sample size
SHS Teachers
45
41
JHS Teachers
89
73
Junior High School Students
2,740
349
Senior High School Students
1,265
304
TOTAL
4,139
767
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Table 1 gives the various categories of the target population, namely SHS Teachers, JHS Teachers, Junior High School
Students, and Senior High School Students with their actual population size and sample size. Almost all the SHS Teachers
were sampled since out of a population of 45 teachers, 41 of them were used thus accounting for 91.1% of the population. For
the JHS Teachers, 73 of the 89 were sampled, hence making up 82% of their population. For the Junior High School
Students, it had a population of 2,740, having 349 samples, accounting for about 12.7%. In relation, 304 of the 1,265 were
sampled from Senior High School Students, representing 24% of their population. In summary, the study sampled 767 of the
total population of 4,139, approximately 18.5%. It means a strong representation of teachers and many students are expected
in the study to ensure a complete dataset for analysis.
D. Research Instrument
Data was obtained through a modified Prototype Demo Form from the Rochester Institute of Technology, which was rated by
the specified research respondents. The form assessed the printing kiosk for attributes, such as functionality, performance,
robustness, and workmanship. A five-point scale was used: 100-90, Superior; 89-80, Above Average; 79-70, Average; 69-60,
Below Average; and below 59, Failing. Also, a questionnaire form revised with criteria by Whiteside, Bennett, and
Holtzblatt, 1998; Usability Metrics from ISO 9241 is a major instrument for data collection. There are two parts to the survey
questionnaire: Part 1 of the questionnaire targeted the assessment of the efficiency of the GSM instrument at system error
management, and Part 2 rated the accuracy, effectiveness, and learnability of the printing kiosk. Responses to these facets of
the kiosk's performance were rated on a four-point Likert scale.
IV. Results and Discussion
A. Prototype Designing and Development
The architectural framework of the smart coin-operated printing kiosk system as shown in Fig. 2 is designed for users to
interact more effectively and receive efficient notification by including real-time SMS notifications and interactive features.
Basically, in the system, users select documents for printing, then insert their coins for payment; a device verifies the amount
paid before processing the request for printing. The activities herein described are tasks of the central processing unit,
involving the microcontroller and server to ensure smooth running operations. Real-time SMS notifications are triggered at
the end of every transaction to users for verification and alert them in case there is a paper jam or any such issue. It is also
integrated with cloud storage and database that provide security along with scalability in managing data. There are some
interactive features by which users can give feedback or seek help directly from the interface of the kiosk. Therefore, the
above module becomes an all-in-one framework towards better efficiency, user satisfaction, and reliability; thus, this printing
kiosk system is very robust in efficiently managing the interaction of users and their notifications.
Figure 2. Architectural Framework of the study
B. System’s Interface
To achieve a user-friendly environment, there must be software use in printing documents. The software that manages a
vending machine or a system of connected machines must exchange information with the controllers of the machines to
monitor the availability of the products offered, to control the financial flows and operations of the users [10][11].
Fig. 3 shows the administrator connecting the Visual Basic program to the Arduino program to control the functionality of the
coin-operated printing kiosk.
Print Files
Coin-Slot
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Figure 3. Connect Visual Basic Program to Arduino Program
Fig. 4 shows that the administrator has to log in to the admin system to first set the paper in the printer's paper tray, adjusting
predefined watermark copy, and log machine transactions like paper jamming, out of paper alert, and low ink levels. The
other option available to the administrator is changing the password for the admin log-in.
Figure 4. Administrator Login
Fig. 5 displays the administrator page, where the administrator can add paper of different sizes to the printer by selecting the
options shown on the screen. The paper count for each printer tray is also displayed on this page.
Figure 5. Adding Paper
Fig. 6 shows a popup button after a flash drive is inserted into the USB port. Users can then view and select the document
types to print from their flash drive.
Figure 6. Users select file location
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The page shown in Fig.7 displays the required amount of coins to be inserted into the coin slot, as indicated in the subtotal
column. It also features a print button for MS Word documents, which becomes active once the correct amount of coins has
been inserted, allowing the user to proceed with printing their documents.
Figure 7. Printing File
C. Efficiency of GSM device in Handling system errors
Table 2. Efficiency of GSM Device
Efficiency of GSM device in managing system errors
Mean
1. Time to complete a task
3.5
2.Relativeefficiency compared with an expert user
3.62
3. Time to learn criterion
3.54
4. Time spent on correcting errors
3.70
5. Frequency of help and documentation used
3.72
6. Number of times the user is disrupted from a work task
3.75
7. Number of times users need to work around a problem
3.76
8. Number of errors
3.77
Overall Results
3.67
Weighted Mean Descriptive Interpretation
1.00 – 1.74 Not Efficient
1.75 – 2.49 Moderately Efficient
2.50 – 3.24 Efficient
3.25 – 4.00 Very Efficient
According to the teacher and student respondents, the GSM device of the printing kiosk is rated to be "Very Efficient" with a
Mean = 3.67, in handling system errors as was experienced during pilot testing and trials conducted by the respondents as
shown in Table 2. These findings are very similar to those obtained in a study by the AMA Computer Engineering
Department, which reported that 45% and 40% of its respondents rated the efficiency of coin-operated printing machines as
"Very Satisfactory" and "Excellent," respectively.
This proves that some of the mistakes which were identified during the pilot testing were actually noted by the system, which
sent an SMS to the researcher about the problems in the machine. All these errors were resolved on time by the researcher
following the notifications.
D. Express the level of user interaction in the machine
Table 3. Accuracy of Kiosk Printing
Accuracy
Mean
Interpretation
1. The number of pages to be printed is equal to the
amount requested by the printing kiosk.
3.12
Accurate
2. The number of coins inserted is correctly recognized and
2.62
Accurate
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counted.
3. The system correctly displays the file/s to be printed.
3.25
Very Accurate
4. The onscreen instruction is accurate.
3.08
Accurate
5. Ratio of success to failures
3.10
Accurate
6. Number of times user expresses frustration or
satisfaction
3.70
Very Accurate
7. Number of times user loses control of the system
3.20
Accurate
8. Number of available commands not invoked
3.23
Accurate
Overall Results
3.16
Accurate
Weighted Mean Descriptive Interpretation
1.00 – 1.74 Not Accurate
1.75 – 2.49 Moderately Accurate
2.50 – 3.24 Accurate
3.25 – 4.00 Very Accurate
As shown in Table 3, the teachers and students of both Senior and Junior High School in Sogod National High School have
responded that the printing kiosk is "Accurate" in printing documents in relation to the amount required by the system with an
overall mean of 3.16. The buttons on the screen were also said to be real-time, reflecting accurate functionality.
Moreover, it can be noted that all the respondents liked the accuracy of the printing kiosk's overall functionality when tested
for real applications. Even though there were some cases wherein the coins were recognized but not continually counted with
those already deposited in the coin collector, the system usually gave an accurate countdown and the correct number of
prints.
Table 4. Effectiveness of Kiosk Printing
Effectiveness
Mean
Interpretation
1. Percentage of goals achieved
3.35
Very Effective
2. Number of power features used
3.45
Very Effective
3. Percentage of functions learned
3.38
Very Effective
4. Percentage of errors corrected successfully
3.50
Very Effective
5. The printing kiosk process input data fast.
3.47
Very Effective
6. Error/s in the input data is easily corrected.
3.17
Effective
7. Printing of files is fast.
3.45
Very Effective
8. Viewing contents of the file/s to be printed is fast.
3.49
Very Effective
9. An SMS is sent immediately to the researcher if paper jam
and no paper fed were detected.
3.62
Very Effective
Overall Results
3.43
Very Effective
Weighted Mean Descriptive Interpretation
1.00 – 1.74 Not Effective
1.75 – 2.49 Moderately Effective
2.50 – 3.24 Effective
3.25 – 4.00 Very Effective
As can be seen in Table 4, the printing kiosk, according to teachers and students, is rated as "Very Effective" in performing
its functions, with a general mean of 3.43. The need to correct errors on the input data was considered "Effective" with an
average mean of 3.17, which implies that the printing kiosk is very effective in viewing and processing input data, with very
minimal errors during actual operation. It also shows that the kiosk meets the expectations of the respondents insofar as it is
effective for doing their printing jobs.
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Table 5. Learnability of Kiosk Printing
Learnability
Mean
Interpretation
1. On-screen instruction is very clear and easy to follow.
3.54
Excellent
2. An “error” message will pop-up if wrong input is done.
3.62
Excellent
3. “Back” screen menu is available in the system to go back to previous
step.
3.62
Excellent
4. Instructions are simple and easy to understand.
3.66
Excellent
5. First time users can use the printing kiosk with ease and accuracy
3.70
Excellent
6. Simple instruction is provided for users to follow.
3.62
Excellent
7. The printing kiosk is generally user-friendly.
3.72
Excellent
8. Number of times interface misleads the user
3.72
Excellent
Overall Results
3.65
Excellent
Weighted Mean Descriptive Interpretation
1.00 – 1.74 Poor
1.75 – 2.49 Average
2.50 – 3.24 Good
3.25 – 4.00 Excellent
Table 5 reveals that respondents were able to manipulate the printing kiosk easily by simply following the instructions
provided and displayed on the screen. An overall mean of 3.65, with a descriptive interpretation of “Excellent,” indicates that
the printing kiosk was very easy to operate, even for first-time users. This further implies that both teachers and students were
able to use the printing kiosk effectively and admirably, even without assistance from the researcher.
E. Prototype Demonstration and Evaluation Form result
This section presents the results of the printing kiosk evaluation conducted by 10 IT experts from Southern Leyte, using the
adapted "Prototype Demonstration and Evaluation Form" from the Rochester Institute of Technology.
Table 6. Prototype Evaluation Result
Attributes
Percentage
Interpretation
Functionality
89
Above Average
Performance
90
Above Average
Robustness
89
Above Average
Workmanship
95
Superior
Overall Result
91
Superior
Weighted Mean Descriptive Interpretation
100.00 - 90.00 Superior
89.00 - 80.00 Above Average
79.00 - 70.00 Average
69.00 - 60.0 Below Average
59.00 - Below Failing
As shown in Table 6, the functioning and robustness of the printing kiosk were rated 89% by the evaluators, while
performance received a rating of 90%. Workmanship was rated the highest at 95%. The overall rating for the printing kiosk
was 91%. With these results, the kiosk has successfully met all the attributes it was evaluated on by the assessment of the IT
experts using the adapted "Prototype Demonstration and Evaluation Form" from the Rochester Institute of Technology.
V. Conclusion
Based on the findings, it is realized that the developed coin-operated printing kiosk is a reliable solution for the provision of
practical, instant, and convenient printing services within the school campus. This kiosk will greatly reduce the need for
students to leave the campus to print projects, assignments, and other school-related documents. Further, this study finds out
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that the accuracy, effectiveness, efficiency, and learnability of the kiosk are highly acceptable to users. This printing kiosk is
therefore targeted to benefit not just students and teachers at this particular school but the entire school at large and
prospective entrepreneurs that may be eying this kind of business.
V. Recommendation
Based on the findings and conclusions, a refinement of the printing kiosk design is proposed to include:
1. Integrated printer: be furnished with a single printer with a more versatile paper tray, accommodating short, long,
and A4 sizes, storing reams of bond paper for improved functionality and convenience.
2. Improved Payment Facilities: A paper bill slot/acceptor should be fitted in the kiosk alongside the coin acceptor.
This will enable the kiosk to accept paper bills and return change in case the amount inserted is more than that
demanded. Or may apply a cashless payment method.
3. Ergonomic and Aesthetic Improvements: Further research on the design should be conducted to ensure that the
printing kiosk is more ergonomically effective and more pleasing in appearance to potential users.
Acknowledment
The authors would like to extend their sincere appreciation to each one that made this piece of research a success. They are
overwhelmed with appreciation for Almighty Lord, Who kept them steadfast and directed through every challenge their
research encountered.
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