Fire Fighting Controlling Robots Used in Dangerous Situations

Robots can be used in many applications in industries, military, domestic. One of the major uses of Robots is an asset to human beings. Whether it is any kind of hazardous situations like a fire breaking out or a place full of landmines, Robots can easily work out a way out of these problems. So let us see these two types of Robots – A Land mine sensing Robot and a Fire Fighting Robot

Land Mine Sensing Robot

How to Sense Land Mine with Robots?

One of the most important applications of Robotics is in defense. A robot in military is actually a remote controlled vehicle with many unique features. It can be a robotic vehicle with a camera to spy, a robotic vehicle with a LASER gun to detect and destroy targets or a robot with a metal detector to detect the presence of land mines.

One of the traditional and conventional ways of mine detection is the use of trained personals that manually search for metals or mines using a metal detector. However this is unsafe and expensive and also slow.

To overcome this problem a far more advanced system is preferred.

A Couple of ways to Detect Landmines:

• Using a robot which can insert a probe into the ground which can detect the objects beneath the soil and determine the type of material.
• Using a robot with a metal detector which can sense the presence of conductive elements like land mines and alarm the user.

Before going further into details about the second type – i.e. the robot with metal detector, let us have a brief recall of the two important terms – Land Mines and Metal Detector.

A Land mine is an explosive device placed deliberately beneath the ground which explodes when triggered by pressure. According to a statistical report there are about 100 million landmines in 70 countries across the world. A landmine once placed can work upto 50 years. Isn’t it dangerous!!

A basic metal detector works on the principle of faraday’s law of induction. It basically consists of a coil which is energized to develop pulsating magnetic field around it. When the coil comes in vicinity of a conductive element like a metal (a mine), an electric current (eddy current) is induced in it. The induced eddy current causes development of electromagnetic field around the metal, which is retransmitted to the coil which develops an electric signal that is analyzed. Greater is the distance between the coil and the metal, weaker is the magnetic field.

A Simple Prototype:

A Simple Prototype of Robotic Vehicle with Metal Detector

Designing the Robot:

The robotic vehicle consists of the following units:

• A rectangular base to support the whole robot structure, attached with two wheels for motion.
• A couple of DC motors to provide required motion to the robot.
• A control unit consisting of a RF receiver which receives command signals from a transmitter unit to control the motor driver and control the motors accordingly.
• A metal detector circuit along with a buzzer alarm which is triggered once the metal is detected.

How does the Robot Works:

The metal detector circuit embedded on the robot control circuitry consists of a transistor which is driven by a tuned oscillator circuit consisting of the coil. When a metal is detected and the electric current is retransmitted through the coil, the transistor1 is in on condition and drives another transistor2 to off condition. This transistor3 in turn drives another transistor to off condition. This particular transistor 3is connected to another transistor4 which is connected such that it in on condition when its driver transistor3 is in off condition. The transistor 4 is connected such that in on condition, the buzzer and the LED are given proper bias and start conducting.

Block Diagram of Metal Detector Unit 

The LED starts glowing and the buzzer starts ringing. Thus when a metal is detected, the buzzer alarm will start ringing and the LED will glow.

Controlling the Robot:

The simple prototype can be controlled using RF communication, which is a short range communication system. The commands are transmitted using a transmitter and received by a receiver embedded on the robot circuit to control the robot motion.

Block Diagram of the Transmitter Section

The transmitter consists of a set of push buttons like forward, back, stop, left and right which are pressed to provide motion of the robot in any desired direction. The push buttons are connected to input port of the microcontroller. The microcontroller on receiving these signals develops a corresponding 4 bit signal in parallel form across another I/O port, to which an encoder IC is connected. The encoder converts these signals to a serial form of data. The RF transmitter modulates this serial data, which is transmitted through the antenna.

Block Diagram of Receiver Section 

The receiver section mounted on the robot consists of the RF receiver which demodulates this signal. The decoder IC receives this signal in serial form and develops a corresponding 4 bit parallel data at its output. The microcontroller receives this data and accordingly provides control signal to the motor driver IC LM293D, which drives both the motors.

Fire Fighting Robotic Vehicle:

The concept of fire fighting robotic vehicle is fighting in a fire. In recent years there have been number of serious accidents including fire and bomb blasts. We have been know about major fire accidents like nuclear power plants, petroleum, gas tank and chemical factories, large scale fire industrial companies in this places once started fire, can result is very serious. The thousands of peoples have been died in this incidence. That is fire fighting robotic vehicle technology.  This robotic vehicle used to find the fire and fight for the fires.

Fire Fighting Robotic Vehicle 

Working Principle of Fire Fighting Robotic Vehicle:

The robot vehicle loaded with water tanker. The pump is controlled by wireless communication (RF and Mobile communication). The transmitter end connected to the push buttons. Using this pushbutton commands are send to the receiver and control moment of the robot like forward, backward, left, right. The receiving end three motors are connected to the microcontroller.

Transmitter Block Diagram 

Receiver Block Diagram 

RF transmitter acts as RF remote control where range is 200 meters. In the home, offices and industries the fire sensors are kept in certain places, when fire occurs near a fire sensor. The sensors are sense that corresponding bit is transmitted to RF receiver. The RF receiver is integrated with microcontroller. When the RF receiver receives the signals that information is passing to the microcontroller the robot is moves towards fire sensors. The sensors locations are stored in the microcontroller. Once the robot reaches to the desired location then the robot stops and activates the sprayer to that fire. After firing the robot goes to initial position. The whole circuit is controlled by the microcontroller.

Types of Fire Fighting Robotic Vehicles:

Home Fire Fighting Robotic Vehicle:

The field action is constrained on the current Flore of house. This robot is using many house hold items catch fire when some one is sleep or away.  This robot is used to secure the home and using this application all doors are opened in the Flore because this vehicle is moving one place to another place in the home. The fire fighting area is must be safe not to cause a new accident. The additional feature of this robot is to operate at long distance.

Industrial Fire Fighting:

Most of industries are faced a fire accidents problems like gas, petrol, nuclear power plants, chemical industries huge amount of damage and more number of peoples is dead near surrounding areas. This robot has the strength to carry a fire around inside burning area to supply unlimited water. Fire causes lowered visibility, extreme heat and many more situations that can be lead to injuries.

Forest Fire Fighting:

Forest Fires is very dangers. It can be short time burning large amount of forest area. Even city fire departments have to deals with forest fires in the area surrounding city. Some years back about 152 fire fighters were killed in 1990s. The forest fire robotics are using to catch the fire and fighting on fire. This robot uses an external control device for wireless communication purpose. The module is connected with the ouput end of which is used for the forest fire extinguishing of the robot. The applications like pressure sensor, temperature sensor, smog sensor, infrared sensor, are used for controlling the forest fire fighting robot.

A la prompt!

While I have given a basic idea of the robot with a metal detector, a major question still exists- How to guide the robot on uneven terrains which are actually unknown, especially in environments subjected to heavy rains, dust and hot temperature range. So find an answer and do post your comments.