Objectives
There are a few objectives that need to be met to get this project done: These objectives will act as a guide and restrict the system to be implemented for certain situations:
- To develop a model of REAL TIME WIRELESS FLOOD MONITORING SYSTEM by using the ultrasonic sensor to measure the water depth in the river.
- To send this water level value from the transmitter module to the receiver module in the control room using the RF transceiver.
- To display the water level using LCD. Then Depending on the measurements of the previous years for the same river we also have a set of LEDs to show the current value of the water level located in which level (safe, medium, or risky).
- To use Keil (IDE) Micro Vision software to generate a computer program for the microcontroller to get signal in real-time.
Significance of the projects
This project aims to conceive a model of a water level detection system as a subsystem of the overall control system of the river flow management system.
- LED with a green color means that the water level is still at the safe level.
- LED with a yellow color means that the water level at the area between the safe level and the level of risk (medium level).
- LED with a red color means that the water level has reached the level of risk (flood level).
And then if the water level rises or falls rapidly to a dangerous level a buzzer shall be set to go off.
Proposed Approach and Methods to Be Employed
Some of the things that were done in the course of achieving the successful result of this project include the following: To achieve this project in the first instance, a lot of research work had to be done such as reading books and other reference materials, journals on flood monitoring system, and various internet sources, as well as the data sheets of the various components to be used for the successful completion of the project. Finally, the used components can be divided into two groups: hardware and software components of the system. Hardware part consists of some components such as Hardware part consists of some components such as:
- The Ultrasonic ranging module HC – SR04.
- RF transceiver.
- Microcontrollers.
- The Liquid Crystal Display (LCD).
- The Light Emitting Diodes (LEDs) and the buzzer.
The microcontroller is the ―heart of the whole system because it controls all the hardware components of the vehicle. where it takes input signals from the sensor and then translates them into the water level on the Liquid Crystal Display (LCD), controls the Light Emitting Diodes (LEDs), and the buzzer. These will be done based on the program without any compromise on the rules and regulations.
The software part includes the whole part of programming that is required to make the microcontroller work properly. Programs that are coded help determine how the microcontroller behaves and functions depending on the situation such as interpreting the signal from the sensor as well as control of the LEDs blinking and the buzzer as a warning when an alarm occurs. The micro-controller has the option of using Cprogramming or Assembly Language for the development of an exclusive main software application for the software application. In the case of programming this and the following goals, a lot of effort is needed to make software. Some of the activities that will be implemented in the course of the project include circuit designing, getting the components, constructing the prototype, verifying the simulation, testing the functionality of the particular prototype, and at the end, diagnosing the circuit and troubleshooting the defects.
Background of ultrasonic distance measurement
The ultrasonic distance sensor is one of the electronic sensors that are equally important in measuring the distance to a reflected object using high-frequency sound. Remember how bats can identify the nearness of the barriers by emitting shrill Sounds and then hearing back the echoes. These Ultrasonic distance sensors are used to send out a series of Supersonic waves and wait for the same type of waves to be bounced back. As the speed in the air is constant and equivalent to 340. 29 meters per second, the time difference between the transmitted signal and the received signal is calculated and thus the distance of the object is identified
Ultrasonic distance measurement depends on the speed property of sound, where an ultrasonic pulse is emitted from the first object and is reflected by the second object as it travels through the distance separating the two objects. Others with drenching impact, sound waves are shot out into the air more than once from the system. These are waves in an environment and upon encountering an object, they bounce off in what is referred to as an echo from the point of origin. These consist of the sound waves that are reflected (or echoed) back to the system. The time between getting the source to emit the sound waves and receiving the echo is calculated. 1. At time t0, through the vibration of a piezoelectric crystal plate or a diaphragm element, the transducer generates the required sound waves. At the first time; that is t1, sound waves interact with an object. At this particular time t2, the waves have somehow reflected off the object and are now moving back to the transducer. At point t3, the echo has lessoned on the transducer because these waves are felt by the transducer. The system subtracts t0 from t3 to determine the total time the sound takes to travel the distance as illustrated below.
The time taken by the sound to travel is then multiplied by the speed of the sound to determine the total distance the sound has been traveling. This distance is then divided by two to get the distance to the object that eventuated the echo. These are outlined in the following equation: Eq.(2). 1, where S is the distance in meters the sound wave has traveled between the transducer and the detected object, V is the speed of sound in meters per second and t is the time taken in seconds between transmission of the sound wave and receiving the echo back.
The advantages of the ultrasonic distance sensor include; Since the ultrasonic distance sensor operates by using sound waves it is not influenced so much by the color or the material of an object. While it may not have such a tight field of view compared to the laser range finder that we looked at earlier it is still possible to measure distances within a meter with the tool. These ultrasonic sensors are made in a way so that they are not affected by external factors such as system vibrations, infrared radiation, loud sounds, and electromagnetic interference radiation. If it uses high frequency of the transducers it will offer a high cost of ultrasonic range finder. With a frequency of around 255 KHz, the ultrasonic range finder costs up to 100-200 dollars, but with a moderate frequency of 40 KHz, there is a way cheaper option.
Selection of the ultrasonic sensor
There are varieties of ultrasonic range sensors that can be categorized by the main differences in the aspects of the frequency and the power consumption. Ultrasonic sensors with high frequency will cover only a narrow area but can sense barriers at large distances. Some of the new sensors offer similar range detection and performance as older models but consume less power than the latter.
For this project, the ultrasonic sensor ranges shall be between 2cm and 400 cm to detect the respective obstacles or objects. As the whole system power supply will be from a battery supply hence it is desirable and necessary that less current should be consumed and also must function at low voltages. Therefore, due to the HC-SR04 has all these characteristics it can be used to meet the criteria of this project by detecting the obstacles within a short time after the research that has been conducted on the HC-SR04 and other ultrasonic sensors.
The radio frequency module (RF module)
What is an RF Module?
An RF module (radio frequency module) is well known as a generally compact electronic unit tendency and/or able to receive radio signals between two gadgets. In most of the embedded systems, it could be beneficial to exchange information with another device without using a wire. It may be a wireless communication using either an optical communication link or a Radio Frequency (RF) link. RF is a medium often used for many applications because it need not be a direct line of sight. RF communications use a transmitter as well as a receiver.
RF modules are characterized by integrating radio circuits in electronic design due to the complexity of designing the circuitry. Good electronic radio design is tough because of the geographical radio sensitivity and the reliability of quantities and arrangements necessary to operate on a certain frequency. Furthermore, the manufacturing of reliable RF communication circuits needs specific control to be put in place to minimize the chances of the fabrication process impacting negatively on the RF performance. At last, the radio circuits are generally exposed to some constraints on regulatory emissions; thus require Conformance and certification from at least a standardization body like ETSI or FCC. These reasons are further valid to explain why design engineers will design a circuit for an application that needs radio communication, and then ‘plug in’ a ready-made radio module instead of engaging themselves in the discrete mode of operation since this may consume much time and money.
RF modules are used in the mid to low-volume products that are required in different consumer-based products such as garage door openers, wireless alarm systems, industrial remote controls, smart sensors applications, and wireless home automation systems. Sometimes, they are applied instead of the more archaic infrared communication designs since these specific devices can operate without the need for a direct line of sight.
Different frequencies are found in typical commercially off-the-shelf RF Modules that operate within the ISM radio bands such as 433 MHz. Popular frequencies available are 92MHz, 315MHz, 868MHz, 915MHz, and 2400MHz Due to some national and international requirements required for the usage of radio for communication.
RF modules can operate at a fixed RF communication protocol that can be Zigbee, Bluetooth Smart, or Wi-Fi or can have a Custom employed RF protocol.
Types of RF modules
RF Module can refer to a wide range of very small circuit board-sized circuit modules, of various, shapes and sizes. This can also be extended toward modules virtually everywhere on functionality and capability scales. RF Modules generally include a Printed circuit board, transmit/receive circuit or circuitry, Antenna, and a Serial I/O for interfacing with the host processor.
Rich trendy electronic markets offer a broad variety of RF Modules & Solutions for diverse purposes. In our current stock list, we have several of these types that are classified using many parameters such as module type, data rates, range, RF band, certification, power consumption, packaging type, and several others. The parametric filters will enable research based on certain parameters or criteria that meet the specified standards.
Most standard, well-known types are covered here:
- Transmitter modules.
- Receiver modules.
- Transceiver modules.
- System on a chip module.
Transmitter modules
An RF transmitter module is a compact printed circuit board (PCB) component designed to transmit radio waves and modulate them to carry data. These modules are typically used in conjunction with a microcontroller, which supplies the data to be transmitted. RF transmitters must comply with regulatory requirements that set limits on transmitter power output, harmonics, and band edge specifications.
Receiver modules
An RF receiver module receives and demodulates the modulated RF signal. There are two types of RF receiver modules: super-heterodyne receivers and super-regenerative receivers. Super-regenerative modules are typically low-cost, low-power designs that use a series of amplifiers to extract modulated data from a carrier wave. However, they tend to be imprecise, as their operating frequency can vary significantly with changes in temperature and power supply voltage. Super-heterodyne receivers, on the other hand, provide better accuracy and stability across a wide range of voltages and temperatures. This stability is achieved through a fixed crystal design, which makes them more expensive compared to super-regenerative modules.