There are two methods to increase transmission range of 434 MHz RF Tx module. 1. Increase applied input power – transmitted power2. Attach an antenna to Tx module In previous article I have explained first method. Please refer previous article of this series. In this session we will see another method. That means we will attach an antenna to Tx and Rx module. Antenna is a special type of transducer, which can convert alternating current in to radio frequency fields and vice versa. Transmitting antenna generates RF fields, and receiving antenna converts RF fields in to alternating current.
There are many devices for visually impaired people. This project is also an attempt to develop an aid for visually impaired persons. This project is a smart stick which is capable of detecting any obstacle, detect water and corners and even allow the user to find the stick if anyhow missed by the user by pressing a remote switch.The device is designed with an intention to sort out common issues faced by the blind people while using traditional sticks. With the electronics embedded within the stick, it became a smart stick with the functionalities mentioned above. The smart stick is built on Arduino Pro Mini. This Arduino board is small enough to install on a regular stick and has buzzer, LDR sensor, Ultrasonic sensor and a water detector sensor interfaced to it.
Distance measurement is a part of the day to day life. Sometime, the size of a room need to be measured before shifting and adjusting furniture into it or the dimensions of a table need to be measured for selecting it for study. Measurement of distance is something that is often done in daily life. Usually, for measuring distances, a measuring tape is used. However, the use of measuring tape has certain disadvantages. First, it requires two persons to hold the measuring tape for taking a reading. Secondly, measuring tape requires careful alignment along the dimensions under measurement and the reading need to be taken carefully . Even sometimes measuring destination is not properly reachable or approachable. Considering these common disadvantages of the use of measuring tape, the idea of an ultrasonic distance measurer came up as a viable electronic solution for the problem.
Fire hazards are not uncommon. In order to avoid damage from fire accidents, smoke detectors are installed at high-security places. These smoke detectors detect smoke as the fire breakout and invoke an early alarm. This way, before the fire spreads to other parts of the building, people can be evacuated and countermeasures can be done immediately. In this project also a smoke detector has been designed. The smoke detector developed in this project not only invokes an alarm but also activates an exhaust fan so that smoke could be removed with immediate action. For the demonstration purpose instead of the actual exhaust fan, a DC motor has been operated in the project. The concentration of smoke is detected by the MQ-6 sensor and displayed on an LCD display.
Gas leakage has been a cause of severe hazards. Many fire accidents in hotels, restaurants, and houses have been due to leakage of LPG gas. Though the leakage can be detected by the smell of the gas, many times it is not possible to sense a leakage straight forward. That is why, hotels, restaurants and even in houses, it is wise enough to install an LPG gas leakage detector.This project is an implementation of the same using MQ-6 gas sensor. The sensor is commonly used for detecting gas leakage for various applications. The device generates a visual alert using LED on detection of a dangerous leakage. It also opens an outlet by driving a servo motor so that the leaked gas could be evacuated. The device also keeps displaying the leakage amount on an LCD display.
Stadium lights consume a lot of electricity. They are high beam lights with high wattage rating. A lot of electricity can be saved by controlling the intensity of these lights manually or automatically. For controlling the intensity of light, the voltage supply to the lights needs to be controlled. This project is a demonstration of the same application. In this demo project instead of actual stadium lights, LED lights are used.A series of 8 LEDs are used to demonstrate intensity control functionality. For manual control of light intensity, a variable resistor is used and for automatic control of light intensity, an LDR sensor is used. The LEDs are connected in two series via 2N2222 transistor. The transistor acts as an amplifier whose output is driven by the voltage at its base pin. A set of two switches is used to set the automatic or manual mode of project’s operation.
Alcohol detectors are commonly required by the law enforcement. The police need to catch and check people who drive after taking alcohol. Driving after taking alcohol can result in serious accidents. People who drive after consuming alcohol not only risk their own life but also of others. That is why police need to remain alerted and verify any person who they found suspicious of driving after drinking. For the verification, they use an instrument called alcohol detector. This project is aimed at building a similar device which will detect the consumption of alcohol by a suspect and display a digital reading indicating the level of alcoholic consumption. The device will also have a dial which will rotate and an LED indicator which glows to indicate a dangerous level of consumption by a suspect.
From the previous project, it has been already learnt to configure control parameters of a Bluetooth Module. In this project, it will be demonstrated that how two Bluetooth modules can be paired together and allowed to share data between them. For pairing of two Bluetooth modules, one of them needs to be configured to Master role and other needs to be configured to Slave role. Apart from this, both modules should be in Order Response Work Mode so that AT commands can be passed to them. The baud rate of the two modules also need to be same and SPP and INQ must be initiated in both the modules. In order start sharing data between the modules, both the modules should have communication mode enabled by setting CMODE parameter set to 1.
In the previous project, how Bluetooth module can be configured to operate in Order Response Work Mode was discussed. The previous project also detailed the AT commands available for the HC-05 Bluetooth module. The AT commands can only be used in Order Response Work Mode. The AT commands are very useful and can be used to change or set multiple control parameters of the module. In this project, some of the AT commands will be used and tested. The project will demonstrate using AT commands to change device name, password, mode and baud rate of the module. In the end of the demonstration, the default settings will be restored using the AT commands.
Servo motors are commonly used for precise rotational motion. The rotational motion can be directly utilized like in the speed dials of cars or converted to linear or translational motion with the help of gears. However, the servos may be used in a project, their precision of motion is their prime advantage. The angle of rotation of a servo can be acutely controlled to a single degree of rotation. The servos are controlled by pulse width modulation technique. Usually, servos can rotate between angle 0° and 180°. Like if the pulse width applied to the control terminal of a servo be 2 milliseconds for which it rotates to 180°, then for a pulse width of 1 millisecond, it will rotate by 90°.
Humidity and temperature monitoring systems are quite common in industries. These environment factors need constant supervision to maintain reliability and efficiency of the industrial devices. The monitoring systems used in industries are generally wired where sensor unit and the sensor monitoring system connects through a cable wire.The humidity and temperature monitoring systems can be made wireless using the 434 RF modules. With wireless connectivity, the sensor and the monitoring systems can be installed separately and industrial equipment can be remotely supervised. Plus, the cost for extensive cable installation is also saved.
Personal computers are usually connected to each other through network cables in a LAN based office network. Connecting two computers using USB cable or RS – 232 cable for data communication is feasible option when the two systems are placed nearby. Also, a single network cable connects a PC to only another single PC. If computer systems in an office are made to communicate data wirelessly, the cost to install elaborate network cable wiring can be saved and the entire setup looks more neat and clean. This way any computer can be connected to any other computer without any fuss. A single computer can also be easily connected with any number of other computers at a time.
There have been continuous innovations in the automotive industry whether it be the use of Near Field Communication in the upcoming car models or the futuristic self-driving cars. These innovations are driven by one motive and that is to make the drive more and more comfortable and smart or safer. This project is also a similar attempt to make the car drives safer by modifying the headlights to adaptive headlights.In this project, this innovation has been realized using the Arduino boards and connecting the servo motor circuit to the control circuit installed at steering through 434 RF Module. Instead of modifying a car’s body to the change Headlight’s assembly, the project has demonstrated the application using the LEDs mounted over RC servos.
It is common to use display screens at railway stations, airports, bus stands and other public places to show messages or alerts. Like at railway station, display boards are installed at the platform to show the alert of train coming to the platform and show the coach numbers at the particular spot of the platform. Similar displays are used at airports and bus stands to display useful information for the travellers. Even in banks and offices, displays are used to show current token number or other customer relevant information. These display boards get the information to be displayed through a computer. Often the computer and the display board are connected through a cable wire for data transmission.
Temperature monitoring and control is one of the most common applications used in the industries. A lot of industrial equipment require constant supervision of temperature like boilers and chemical containers need continuous supervision of equipment or the ambient temperature. Many times, the operating temperature range of the system under supervision is in limits where hardwiring the sensor circuit with the control circuit is not feasible. In such a case, the temperature sensor can be made to transfer temperature readings to the control circuit using wireless mode.This project is an implementation of wireless temperature reading using the 434 RF module. It has a range of 50-60 meter and can be extended to 300-350 meter using the antenna with RF module and increasing its transmission power.
Distance measurement has important applications in automotive and industrial applications. The distance measurement through sensors is useful in detecting obstacles and measuring the fluid levels in automotive tanks and containers. It is the distance measurement feature that allowed to imagine of self-driving cars and robots. Without a technology that may have allowed to measure distance from an object or obstacle, self-driving concept would have never been thought.The distance measurement application is also used in industries to check fuel levels in aircrafts and commercial transport vehicles. The application is used in robotics to equip autonomous robots detect obstacles and find an accessible path. This project is also a distance measurement application using ultrasonic sensors.
The transmission of digital data over an RF module is quite common. The 434 RF modules are capable of transmitting 4-bit data along with the address byte. The circuits using RF modules for digital data transmission are simple and uses HT12E encoder and HT12D decoder ICs for parallel to serial and serial to parallel data conversion respectively.In real-life situations, the source of digital data are only the computers, microcomputers or digital ICs. The real world isn’t the digital, it is analog. Like, the most sensors actually are analog sensors and they are capable of transmitting the analog data to a digital form only when a microcomputer process it from analog to digital form.
Water is the first necessity of all mankind and humans have been smart enough to keep storage of it. Water tanks have been common in the households since the civilizations started advancing. Almost all the modern households have underground or roof-top water tanks these days and these tanks are filled with water through AC motors. An AC motor does its work but is not smart enough to detect water levels and start or stop on its own accordingly. This project is all about adding the intelligence to the water regulation system of a household.
The intruder alarms are quite common in the industries, offices and high-security homes. One such kind of alarms can be made using LDR (Light Dependent Resistors). A lot of LDR based alarm systems use wired connection between the sensor and the alarm circuit. This project uses a wireless RF module to connect the sensor circuit with the alarm circuit of the intruder alarm system. The benefit of using an RF module for triggering the alarm circuit through sensor circuit is that many alarm circuits installed at different places in a building can be interconnected to a common sensor circuit. Therefore, it becomes possible to send alert to many security guards standing at different places in a building when an intruder tries to violate access to a secured block of the building.
Home automation is the new trend picking up these days in many households. With home automation every electrical and electronics appliance used in home gets remote controlled. Along with remote controlling lights, fans, air conditioners and kitchen appliances, regulation of water supplies is also a part of home automation projects. This project is a demonstration of similar automated water supplies regulation by placing an electronically automated valve to the water tanks. The valves at the opening of the tank’s pipeline restrict the flow of water from it by contracting and closing the pipe’s opening. The typical valves need to be operating manually by opening or closing the valve through rotating the valve handle.