TRIBHUVAN UNIVERSITY
INSTITUTE OF ENGINEERING
ADVANCED COLLEGE OF ENGINEERING AND MANAGEMENT
DEPARTMENT OF ELECTRONICS AND COMPUTER ENGINEERING
KALANKI, KATHMANDU
[EX707]
A Major Project On
”REVERSE VENDING MACHINE”
Submitted By:
Aayush Bishwakarma ACE078BEI003
Akash Baral ACE078BEI005
Animesh Man Baisyet ACE078BEI007
Badri Rana Magar ACE078BEI015
A Major Project Proposal report submitted to the Department of Electronics and Computer Engineering
in the partial fulfillment of the requirements for degree of Bachelor of Engineering in Computer
Engineering
Kathmandu, Nepal
June 10, 2025
ACKNOWLEDGEMENT
We take this opportunity to express our deepest and sincere gratitude to our Department
of Electronics and Computer Engineering for his insightful advice, motivating sugges-
tions, invaluable guidance, help and support in this project selection and also for his
constant encouragement and advice throughout our journey till the date.
We express our deep gratitude to Er. Roshani Ghimire, Head of Department of Elec-
tronics and Computer Engineering, Er. Navaraj Banstola, Deputy Head, Department
of Electronics and Computer Engineering for their regular support, co-operation, and
coordination. We also like to express our sincere gratitude to Er. Rakshya Dangol for
her advice, help and support, invaluable guidance in this project selection.The in-time
facilities provided by the department are also equally acknowledgeable.
We would like to convey our thanks to the teaching and non-teaching staff of the
Department of Electronics & Communication and Computer Engineering, ACEM for
their invaluable help and support hitherto. We are also grateful to all our classmates for
their help, encouragement and invaluable suggestions.
Finally, yet more importantly, we would like to express our deep appreciation to our
grandparents, parents, siblings for their perpetual support and encouragement.
Aayush Bishwakarma ACE078BEI003
Akash Baral ACE078BEI005
Animesh Man Baisyet ACE078BEI007
Badri Rana Magar ACE078BEI015
1
ABSTRACT
Increasing international awareness of sustainability and waste management has indeed
highlighted the importance of recycled packaging. This report explains the
development of Reverse Vending Machine (RVM) where a bottle is being placed for
the reuse process. The final form of a RVM, which enhances the recycling process for
plastic bottles and aluminum can by picking up collected materials and converting
them into smaller pieces with one automated system.
The RVM takes the plastic bottle and aluminum can by users, identifies what and how
much material each type is in the sorted two parts, then returns a reward such as
money or coupons to them. It is a large contributor to the success of sorting, cleaning
and reproducing later on hence why it marks step 1 in recycling.
Keywords: Waste Management, Reverse Vending Machine,
Aayush Bishwakarma ACE078BEI003
Akash Baral ACE078BEI005
Animesh Man Baisyet ACE078BEI007
Badri Rana Magar ACE078BEI015
2
TABLE OF CONTENTS
1 INTRODUCTION 6
1.1 Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.2 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.3 Statement of the Problem . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.4 Project Objective . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1.5 Significance of the Study . . . . . . . . . . . . . . . . . . . . . . . . . 8
2 LITERATURE REVIEW 10
2.1 Plastic Waste Management and Recycling . . . . . . . . . . . . . . . . 10
Overview of Plastic Waste and Its Management Strategies . . . . . . . . 10
Current Recycling Practices and Challenges . . . . . . . . . . . . . . . 10
2.2 Reverse Vending Machines (RVMs) . . . . . . . . . . . . . . . . . . . 10
Design and Construction of RVM for Recycling . . . . . . . . . . . . . 10
Reverse Vending Machine for Plastic Bottle Recycling . . . . . . . . . 10
3 REQUIREMENT ANALYSIS 11
3.1 Project Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Hardware Requirements . . . . . . . . . . . . . . . . . . . . . . . . . 11
Software Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4 SYSTEM DESIGN AND ARCHITECTURE 12
5 METHODOLOGY 14
5.1 System Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
System Components . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
System Integration . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5.2 Procedures and Algorithms . . . . . . . . . . . . . . . . . . . . . . . . 15
Bottle Detection and Verification . . . . . . . . . . . . . . . . . . . . . 15
Reward Issuance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
5.3 Block Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Sensor Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Control and Output Connections . . . . . . . . . . . . . . . . . . . . . 16
6 EXPECTED OUTPUT 17
7 TIME SCHEDULE 18
8 TOTAL COST 19
3
LIST OF FIGURES
Title Page
Figure 4.1: Block diagram of RVM 12
Figure 4.2: Flow Chart for RVM 13
4
LIST OF ABBREVIATIONS/ACRONYMS
HDPE High density polyethylene, Polyethylene
NPR Nepalese Rupee
PET Polyethylene terephthalate
PP Polypropylene
PVC Polyvinylchloride
RVM Reverse Vending Machine
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1 INTRODUCTION
1.1 Background
Waste is now a global problem, one that must be addressed if the resource and energy
crisis of the world is to be alleviated. The world’s most commonly consumed
substance today is plastic. Five major forms of plastic exist: Polyethylene
terephthalate (PET), High-density polyethylene (HDPE), Polyvinyl chloride (PVC),
Polypropylene (PP), and Low-density polyethylene (LDPE).
Along with plastics, glass is another widely used material—especially in beverage
containers. Glass is 100% recyclable and can be recycled endlessly without loss in
quality or purity. Recycling glass saves energy, reduces raw material consumption
(such as sand, soda ash, and limestone), and decreases landfill use. Despite these
advantages, glass containers are often discarded improperly due to a lack of convenient
and rewarding recycling systems.
Recycling is necessary to protect the environment through the reduction of waste,
preservation of resources, and prevention of pollution. However, the majority of
people still do not recycle enough, especially cans and bottles. The existing recycling
mechanisms that are in use do not give consumers adequate incentives to return used
cans, bottles, or glass containers, and this leads to a large amount of recyclable
materials being wasted instead.
And that is where reverse vending machines (RVMs) can help. The machines collect
used drink containers—plastic, metal, and now glass—and give a reward or cash back
in return, directly motivating users to recycle. They’ve already been successful
elsewhere and have generated some impressive recycling gains.
Experiments have confirmed the effectiveness of RVMs at raising recycling levels. For
example, a German study found that RVMs were a major contributor to over 90%
recycling of drink containers (Morris et al., 2012). The same positive impacts have
been recorded in other nations with established RVM programs (EPA, 2018).
This project aims to create a customized reverse vending machine suitable for our
community to accept plastic, metal, and glass containers—in order to encourage more
comprehensive recycling and significantly reduce our environmental footprint.
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1.2 Motivation
The idea behind the RVM is to tackle the problem of unmanaged waste, particularly
plastic waste, which not only degrades the beauty of our natural landscapes and oceans
but also affects the health of people, the environment, and every living thing on this
planet. By successfully implementing this project, we can make the concept of 3R
(Recycle, Reuse, and Reduce) more efficient. Key points of motivation include:
• Concern about the environmental impact of plastic pollution
• Desire to promote sustainable waste management practices
• Interest in the potential of technological solutions to address environmental
challenges
1.3 Statement of the Problem
Plastic waste has emerged as one of the most urgent environmental issues of our time.
The rapid increase in the production and consumption of single-use plastics,
particularly bottles, has led to a significant accumulation of plastic waste in landfills
and natural environments. Despite growing awareness and initiatives to combat plastic
pollution, the existing recycling infrastructure struggles to keep pace with the sheer
volume of waste generated.
In 2021, the global plastic market was worth approximately USD 600 billion (Merkl
and Charles, 2022). In 2019, plastics generated 1.8 billion tons of greenhouse gas
emissions, with 90% coming from their production and conversion from fossil fuels
(OECD, 2022). Every minute, around 1 million plastic bottles are sold. In Nepal
alone, approximately 4,900 tons of waste are generated daily, with 165,000 tons of
plastic products manufactured annually.
Current recycling systems face several challenges:
1. Inefficient Collection and Storage: The bulkiness of unprocessed plastic bottles
complicates storage and transportation logistics.
2. Consumer Engagement: Traditional recycling methods offer little to no
immediate incentive for consumer participation.
3. Processing Bottlenecks: Downstream recycling processes are hampered by the
need to sort and clean collected plastics, which is labor-intensive and costly.
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1.4 Project Objective
To design the mechanical and electronic components of the reverse vending machines
(RVMs) as a tool for improving plastic waste management and promoting recycling.
1.5 Significance of the Study
The significance of this study lies in its potential to bring substantial benefits to the
environment, economy, and society. The proposed reverse vending machine (RVM)
project aims to address the issue of low recycling rates for beverage containers by
providing incentives to users, thereby encouraging sustainable behavior and
contributing to a cleaner environment.
Environmental Benefits
• Reduction of Waste: The RVM motivates users to return their used beverage
containers and glass, resulting in less waste going to landfills. This helps reduce
pollution and conserve landfill space.
• Resource Conservation: By facilitating the recycling of beverage containers, the
project helps preserve natural resources. Recycling materials consumes less
energy and resources compared to producing new ones, which is beneficial for
the environment.
• Reduction in Carbon Emissions: Recycling processes typically generate fewer
carbon dioxide emissions than manufacturing new materials. By increasing
recycling rates, the project can help lower greenhouse gas emissions and combat
climate change.
Economic Benefits
• Cost Savings: Local governments and waste management companies can save
money on waste disposal as increased recycling leads to reduced waste volumes.
This can result in significant cost savings in waste management.
• Creation of New Markets: A higher availability of recycled materials can
stimulate the growth of industries focused on recycling and reusing materials.
This can lead to economic development and new business opportunities in the
recycling sector.
• Job Creation: The deployment, maintenance, and operation of RVMs can create
employment opportunities. This includes roles in machine manufacturing,
software development, logistics, and maintenance services.
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Social Benefits
• Public Awareness and Engagement: The project can enhance public awareness
about recycling and environmental conservation. By offering tangible rewards, it
encourages community members to actively participate in recycling efforts.
• Convenience and Accessibility: RVMs can be strategically placed in public areas,
making it convenient for individuals to recycle their beverage containers. This
accessibility can lead to higher participation rates in recycling and environmental
stewardship.
• Educational Opportunities: The introduction of RVMs provides an opportunity to
educate the public, especially the youth, about sustainable practices and the
importance of recycling. This can foster a sense of environmental responsibility.
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2 LITERATURE REVIEW
This review aims to identify the current body of knowledge, highlight gaps, and
establish the context for the RVM project. It situates the RVM project within the
context of existing research, highlighting the need for improved solutions in plastic
waste management and the potential benefits of RVMs.
2.1 Plastic Waste Management and Recycling
Overview of Plastic Waste and Its Management Strategies
N. Evode, S. A. Qamar, et al. (2021) have discussed the problems caused by the
inadequate processing of plastic waste and the possible solutions that can be provided
to ensure a good atmosphere and to reduce the causes of climate changes, which is
challenging to life on this planet.
Current Recycling Practices and Challenges
Recycling practices for plastic waste involve collection, sorting, cleaning, and
reprocessing. However, as noted by J. Hopewell, R. Dvorak, and E. Kosior (2009), the
efficiency of these practices is often hampered by contamination and the heterogeneity
of plastic materials.
2.2 Reverse Vending Machines (RVMs)
Design and Construction of RVM for Recycling
This research work is aimed at solving the problems of plastic waste management in
developing countries. R. Tomari, A. A. Kadir, et al. (2016) focused on the
development of a Reverse Vending Machine (RVM) Framework for Implementation to
a Standard Recycle Bin.
Reverse Vending Machine for Plastic Bottle Recycling
A Simple Approach to Design RVM by Aditya Gaur, Dilip Mathuria, Dr. R.
Priyadarshini (March 2018) describes the working of a Reverse Vending Machine
based on fraud detection sensors which start to work after inserting the plastic material
into it and that plastic is checked by a series of sensors.
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3 REQUIREMENT ANALYSIS
3.1 Project Requirements
Hardware Requirements
The hardware requirements for the RVM include:
• Microcontroller: The central unit that controls all operations within the system.
• IR Sensor: Detects the presence of a bottle to initiate the process.
• Capacitive Sensor: Verifies the material of the inserted item.
• Data Logger: Records data from sensors for monitoring and analysis.
• Counter: Keeps track of the number of bottles processed.
• Print Unit: Prints receipts or other information for the user.
• Control Room: Interface for manual control and monitoring, including display
and switches.
• Servo Motor: Moves the bottles/cans on the conveyor belt.
• Gearmotor: Shifts the bottle from entry to storage.
Software Requirements
The software requirements for the RVM include:
• Embedded Software: Software programmed into the microcontroller to handle
sensor data.
• Data Logging Software: Records and stores data from the system for analysis and
monitoring.
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4 SYSTEM DESIGN AND ARCHITECTURE
The system design involves multiple components of the RVM. The architecture is
summarized in the form of block diagrams and flowcharts. This design not only covers
software but also hardware to create an effective solution for plastic waste
management. The use of sensors enables accurate identification and authentication,
with the microcontroller providing centralized control and smooth interaction between
system parts. The incorporation of a simple interface and a rewarding recycling
approach enhances user engagement and contributes to a healthier environment.
Inductive Sensor IR Sensor
Weight Sensor Reward
Capacitive Sensor Microcontroller Counter
Storing
Control Room
Display Switch
Figure 4.1: Block Diagram for Reverse Vending Machine
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Start
Weight Sensor Insert Bottle/Can
NO
Capacitive Sensor Bottle/Can Received?
YES
NO
Counter Bottle/Can Quantity ¿0?
YES
Reward Dispense
Storing Process
Repeat
Figure 4.2: Flowchart for Reverse Vending Machine
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5 METHODOLOGY
This chapter elaborates on the steps and procedures followed to conduct the project,
detailing the sequence of work and the algorithms, procedures, and circuit diagrams
used. The methodology ensures the project meets its objectives effectively.
5.1 System Overview
System Components
1. IR Sensor:
• Function: Detects the presence of a bottle when inserted into the machine.
• Procedure: The IR sensor emits infrared light and detects the reflected signal
to confirm the presence of an object.
2. Capacitive Sensor:
• Function: Verifies the material of the inserted item to ensure it is a plastic
bottle or aluminum can.
• Procedure: The capacitive sensor measures changes in capacitance when a
bottle is placed near it, identifying the material based on its dielectric
properties.
3. Data Logger:
• Function: Records operational data such as the number of bottles processed
and transaction times.
• Procedure: Data is logged in real-time, stored locally, and can be accessed
for monitoring and analysis.
4. Control Room:
• Function: Manages the operation and monitoring of the machine.
• Procedure: The control room interface displays operational status and allows
manual control via a switch.
5. Microcontroller:
• Function: Acts as the central processing unit, coordinating all actions of the
system components.
• Procedure: Receives input from sensors, processes the information, and
sends commands to the output devices.
6. Storing Vault:
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• Function: Stores verified plastic bottles and aluminum cans for collection
and further processing.
• Procedure: The microcontroller activates the servo motor to process the
bottles and store them.
7. Counter:
• Function: Tracks the number of bottles processed.
• Procedure: The counter increments with each verified bottle, providing data
to the microcontroller.
System Integration
All components are connected to the microcontroller, which serves as the central hub
for data processing and control. The sensors send input signals to the microcontroller,
which processes the information and sends output commands to the appropriate
components.
5.2 Procedures and Algorithms
Bottle Detection and Verification
Algorithm for Bottle Detection and Verification:
1. Detection:
• The IR sensor detects the presence of a bottle, Can and Glass.
• If a material is detected, a signal is sent to the microcontroller.
2. Verification:
• The capacitive sensor verifies the material of the bottle or can.
• The AI Trained module verifies the material
• The microcontroller processes the sensor data to confirm if the item is a
plastic bottle or aluminum can.
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Procedure:
1. User inserts a bottle into the machine.
2. The IR sensor detects the bottle and sends a signal to the microcontroller.
3. The capacitive sensor verifies the material.
4. The weight sensor verifies if the bottle/can contains any liquid by measuring their
weight.
5. The microcontroller processes the data and confirms the bottle.
Reward Issuance
Algorithm for Reward Issuance:
1. Once the bottle/can is detected, the counter counts.
2. As the counter increases, a reward coupon is printed out.
5.3 Block Diagrams
The block diagrams illustrate the connections and interactions between the
components.
Sensor Connections
• IR Sensor Circuit: Connects the IR sensor to the microcontroller, detailing the
power supply, signal output, and ground connections.
• Capacitive Sensor Circuit: Shows the connection of the capacitive sensor to the
microcontroller, including power and signal lines.
Control and Output Connections
• Microcontroller Circuit: Central hub connecting all sensors and the printer.
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6 EXPECTED OUTPUT
The expected output of this project is a fully functional Reverse Vending Machine
(RVM) system that can accurately detect and segregate beverage containers using IR
sensors and capacitive sensors to identify the type of container. The system will also
classify containers based on their weight to determine their refundable value.
Additionally, it will incentivize users with monetary rewards or virtual credits for
recycling.
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7 TIME SCHEDULE
Gantt Chart Graph
Week
0 to 5 5 to 10 10 to 15 15 to 20 20 to 25 25 to 30
Integrate IR Sensor
Integrate Weight Sensor
Integrate Capacitive Sensor
Setup Control Room
Program Microcontroller
Connect To Reward System
Setup Storage System
Testing And Debugging
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8 TOTAL COST
The estimated cost for the project components is as follows:
S.N Component Quantity Estimated Cost
(NPR)
1 IR Sensor module 1 140
2 Capacitive Sensor 1 600
3 Servo Motor Mg90s 2 600
4 Gearmotor 630 Metal Motor 4 3,000
5 Inductive Sensor 1 600
6 Weight Sensor 1 700
7 Raspberry PI 4 Model B 1 4,000
8 7-Inch Raspberry Display 1 2,000
9 Lipo Battery 3000mah 11.1V 35C 1 3,000
(XT-60)
10 Lipo Tester 1 250
11 IMAX Lipo charger 1 700
12 Frame and Wires – 3,000
Total 30,000
Table 8.1: Estimated Cost of Components
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Bibliography
[1] N. Evode, S. A. Qamar, et al. (2021). Plastic waste and its management strategies
for environmental sustainability. Case Studies in Chemical and Environmental
Engineering, Volume 4, 100142.
[2] R. Tomari, A. A. Kadir, et al. (2016). Development of Reverse Vending Machine
(RVM) Framework for Implementation to a Standard Recycle Bin. 2016 IEEE
International Symposium on Robotics and Intelligent Sensors (IRIS 2016).
[3] Aditya Gaur, Dilip Mathuria, Dr. R. Priyadarshini (2018). A Simple Approach to
Design Reverse Vending Machine. International Journal of Electronics, Electrical
and Computational System, Volume 7, Issue 3.
[4] J. Hopewell, R. Dvorak, and E. Kosior (2009). Plastics recycling: challenges and
opportunities. Philosophical Transactions of the Royal Society B, 364.
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