Water covers about 70% of Earth’s surface, makes up about 70% of your mass, and is essential for life. Water is acquired by different people from different ways not all people get this water direct from their home only people who are able to afford the government tends to supply this water at their home, but other people buy water simply because they are not able to afford the system to be supplied water at their home by the government(DAWASCO). We know that the available water resources has initiated towards the end. This problem is quietly related to poor water allocation, inefficient use, and lack of adequate and integrated water management. Therefore water controlling system implementations have potential significance in the society. So as it is coin operated system, the required quantity of water and respective amount of money is decided that are affordable to many people.
PROBLEM STATEMENT
Due to the existing system of buying water for domestic activities , a person is employed so as to collect the money from the customers which is costly and time wastage , also there are times when the employed person is not around that place so the customers will have to wait for the service.
PROJECT OBJECTIVES
MAIN OBJECTIVE
To provide an automated water dispenser system that will be used to sell water with water wastage saving feature.
SPECIFIC OBJECTIVES
To design a circuit that will dispense water into a bucket automatically when a coin is inserted in coin acceptor.
To simulate the designed circuit.
To build the prototype.
To test the prototype
SIGNIFICANCE OF THE PROJECT
It will save water
Low cost system
The system will be reliable
METHODOLOGY
These are the ways to go through for my project to be completed.
Literature review
Data collection
Data analysis
Designing of the proposed system
Building the prototype.
Testing the prototype.
Report writing
LITERATURE REVIEW
EXISTING SYSTEM
The existing system involves customers paying the money directly to the person employed and this person controls the system by opening and closing the water tap and customers gets amount of water they paid for.
DISADVANTAGES
It adds cost of employing a person
No service when the employee is absent
Time wastage
Water wastage.
BLOCK DIAGRAM OF THE EXISTING SYSTEM
PROPOSED SYSTEM
In this system, it works on the principle of coin detection when you insert a coin in the slot it will be detected by the sensor and information will be sent to the microcontroller also the system detects if a bucket is present by using IR sensors if both conditions are fulfilled the microcontroller processes the information sent by sensors and on detecting a valid coin and presence of bucket below the nozzle a signal is given and accordingly solenoid valve gets activated and water will be dispensed. If the bucket is removed during the process system stops the water supply until filling utensil is encountered .Thus we here put forward a smart water dispenser system with water saving feature
BLOCK DIAGRAM OF THE PROPOSED SYSTEM
DATA COLLECTION
Number of customers per day =above 40 customers
Amount of money collected per bucket is 200Tshs
Amount of water lost or wasted due to the system of manually controlling the water tap is approximately up to 20 liters per day.
Number of people that misses the service due to absence of employed person = above 10
PROPOSED CIRCUIT DIAGRAM
OPERATION OF THE PROPOSED CIRCUIT DIAGRAM
It works on the principle of coin detection when you insert a coin in the slot it will be detected by the coin acceptor/sensor and information will be sent to the microcontroller also the system detects if a bucket is present by using IR sensors if both conditions are fulfilled the microcontroller processes the information sent by sensors and on detecting a valid coin and presence of bucket below the nozzle a signal is given and accordingly solenoid valve gets activated and water will be dispensed. If the bucket is removed during the process system stops the water supply until filling utensil is encountered .Thus we here put forward a smart water dispenser system with water saving feature and when a certain quantity of water is reached for a set coin the flow meter which measures flow rate senses pulses to the microcontroller and solenoid valve gets deactivated.
DATA ANALYSIS
RELAY AND TRANSISTOR Q1 ANALYSIS
BASE RESISTOR ANALYSIS R1
SELECTION OF SOLENOID VALVE
Solenoid valve is required so that it can be used to dispense water from the reserve water tank.
Due to availability a 3/4 inch 12V DC solenoid valve was selected
SPECIFICATIONS
Working voltage 12V DC
Working current 300mA
FLOW METER ANALYSIS
Flow meter is used to measure the flow rate of water passing from the solenoid.
The pulse signal is a simple square wave so its quite easy to log and convert into liters per minute using the following formula.
Pulse frequency (Hz) = 6.6 * flow rate in L/min.
Features:
Measurement flow range: 1 ~ 30 L/min
Working voltage: 4.7~15 VDC
Working current: ≤ 10 mA (DC 5V)
It gives 450 pulses per liter
So for 1000mL
450pulses=1L
?pulses=100mL
=45 pulses for 100 milliliters
SELECTION OF COIN SENSOR/COIN ACCEPTOR
A coin sensor or coin acceptor is used for customers to put their coins
A COM-11719 coin acceptor was selected as it can be programmed and it can be used for multiple coins.
SPECIFICATIONS
Its working voltage is +12v±10% DC
Its working current is 65mA±5%
Coin diameter is between 15mm -32mm
Coin thickness is between 1.2mm-3.4mm
SELECTION OF FLYBACK OR FREEWHEELING DIODE (D1)
Freewheel diode or Flyback diodes are basically connected across inductive coils to prevent from voltage spikes in case of power getting turned off to the devices. It protects the solenoid coil against back emf. Peak Inverse Voltage (PIV) of the diode has to be greater than system voltage.
For the system voltage of 12V DC
Therefore 1N4001 diode was selected because it has 50V DC since its Peak Inverse Voltage is greater than the supply voltage.
SELECTION OF ARDUINO MICROCONTROLLER
Arduino Uno was selected because of;
Easily available
Low cost
Simple to interface with other components
Effortless functions
SPECIFICATIONS
Operating Voltage 5V
Input Voltage (recommended) 7-12V
Input Voltage (limit) 6-20V
Digital I/O Pins 14 (of which 6 provide PWM output)
PWM Digital I/O Pins 6
Analog Input Pins 6
DC Current per I/O Pin 20 mA
DC Current for 3.3V Pin 50 mA
Flash Memory 32 KB (ATmega328P) of which 0.5 KB used by boot loader
LCD DISPLAY SELECTION
LM016L display was selected because
It is easily interfaced with Arduino Uno
It displays 16 characters with 2 lines
Easily available
SPECIFICATION
Power supply is +5V DC
It requires a variable resistor to change the display contrast.
CONCLUSION
The prototype works well and its performance is good. The implementation of the prototype at Kigamboni will provide an automated coin operated water dispenser system hence solving the problems caused by the existing system of selling water.
RECOMMENDATION
Since the technology changes any person having other methods and different technology is allowed to improve the project.