In general all electrical and electronic devices or loads are to be controlled and operated using their switches and regulators. But, after the remote control technology has been developed, we have got used to operate many home appliances such as televisions, air conditioners, coolers, audio systems, DVD players, car locks and so on through their remotes. Even advancement in technology has developed a programmable remote control device which can be programmed to operate, monitor and control remotely.
Programmable Remote Control
Remote Control Switch is an electronic device used for operating and controlling frequently used electronic loads wirelessly using a wireless sensor within a short line-of-sight distance. In early 1973 ultrasonic tones were used in remote control devices. There are different types of remotes realized using different technologies such as IR remote (Infra Red), RF remote, remote implemented using Android mobile, and so on.
The remote control device is used for controlling the robots; robotic vehicles used in home; military applications using the communication technologies, such as radio frequency, infrared, and so on.
Many modern electronic devices are programmed for operations and control by using a remote control technology. You can observe- in case of below programmable remote control device- it is operated with TV remote for controlling its direction of motion. Many devices that we generally use in home, industrial, military applications are being controlled remotely for obtaining better control and safety.
The remote technology is primarily used for basic electronic appliances such as televisions, audio systems, personal computers (PC) and air conditioners. The programmable remote control devices are increasing in number with development in the technology.
Techniques Used for Implementing Programmable Remote Control
There are different techniques to implement a remote control switch circuit, but frequently used techniques are infrared (IR) and radio frequency (RF).
To control any appliance remotely, a transmitter is used for sending the commands or signals in order to control it, and a receiver is required for receiving the commands sent by the transmitter. For this communication, a medium or technique is required like IR light, RF, etc. And if RF is used for communication, then we must choose the legal radio frequency like 27MHz, 38MHz (such that we should not disturb the aircraft, radio, medical, police or any other registered frequencies).
Recent trends in technology have improved the remote control techniques and innovated the usage of Android mobile phones, touch screen displays and so on for implementing remotes to control different applications: War Field Spying Robot with a Night Vision Wireless Camera by Android Applications; Fire-Fighting Robot Remotely Operated by Android Applications; Pick-N-Place Robotic Arm and Movement Controlled by Android Wirelessly, and so on.
Infrared Remote Control
These remote controls use light and thus, requires line of sight with the operating device for their control. They consists of transmitter section, remote to transmit the command signals and receiver section which is in a stable position in the device intended for controlling to receive the signals.
The infrared light remote control has some limitations such as limited operating angle, line of sight is not maintained and this signal can be reflected by mirrors similar to other light sources. But, in front of the receiver by placing a matte transparent object the operating angle can be increased. By using the IR extenders, the control over the devices can be achieved even though there is no line of sight.
The figure shows the transmitter and receiver section blocks of the IR remote. The infrared light technology is majorly used in home remote control switches. A signal which is invisible to the human eye and which consists of infrared light pulses is used for communication between the remote and the device it is intended to control (television or air conditioner or PC).
But, using a digital camera or video camera or phone camera, we can see these infrared signal pulses (for example, take the TV remote, by pressing and holding any one button on the remote, see the IR led of the remote using your phone camera, you can see light in your phone camera screen which is invisible to the normal eye).
There are different real time project applications of a programmable remote control device and a few of them are as follows:
- Using TV Remote as a Cordless Mouse for the Computer
- RF Based Home Automation System
- TV Remote Operated Domestic Appliances Control
- Dish Positioning Control By IR Remote
- IR Controlled Robotic Vehicle
Infrared Remote (IR) Control for Directing Robotic Vehicle
The infrared remote such as normal TV remote is used to control the movements of the robotic vehicle. The remote is used to transmit control signals to the receiver placed in the vehicle and which consists of an IR sensor along with microcontroller. The command signals are transmitted from the transmitter to the receiver, and these signals are received by the microcontrollerwhich gives an output according to the input and operates the robotic vehicle to move forward, backward, left and right, respectively.
Motor driver ICs are used for interfacing the motors with the control unit. This project can be implemented to control robotic vehicle over long distances by using long communication DTMF technology.
RF Remote Control for Operating Electric Appliances or Devices
This system comes under home automation using an RF remote control switch and it is a centralized control system in which RF controlled switches replace the conventional switches. As the manual operation of conventional switches for all frequently used home appliances such as TV, fan, lights, coolers, etc., is very difficult for elderly and physically handicapped people. This system consists of RF transmitter and RF receiver circuits as shown below.
To overcome these difficulties RF based home automation system is developed. RF remote is interfaced with the microcontroller in the transmitter circuit to send control commands by encoding using an encoder, such as on/off commands to the receiver circuit at the loads, wherein the encoded data is again decoded using the decoder.
Opto-Isolators and TRIACS are used to interface the loads with microcontroller. Thus, an RF remote control switch is used for controlling all home appliances, remotely.
Do you know there are various recent advanced technologies like Android application also used for implementing the remote control? For more detailed information regarding these advanced remote techniques and many innovative real-time electronics and electrical projects using different remote controls such as Android, Bluetooth, DTMF, RF, IR, etc., can approach us by posting your doubts and ideas in the comments section below.