Underground land mines represent a significant threat to human lives and can have adverse effects on a nation’s economy. The manual detection and removal of these mines is a perilous task that carries the risk of accidents. In such scenarios, robots can play a crucial role in locating land mines. These robots possess the capability to detect not only land mines but any metal concealed in the ground. This article introduces the Metal Detector Robotic Vehicle employing RF technology. To gain a comprehensive understanding of this metal detector robotic vehicle, it’s beneficial to first grasp the fundamentals of how a metal detector circuit operates.
Outline
- Wireless Metal Detector Robot Circuit Principle:
- Wireless Metal Detector Robot Circuit Diagram:
- Transmitter Circuit:
- Receiver Circuit:
- Circuit Components:
- Circuit Design of Metal Detector Robot using Microcontroller:
- RF based Metal Detector Robot Circuit Simulation:
- Wireless Metal Detection Robot Circuit Working:
- RF Based Metal Detection Robot Project Output Video:
- Metal Detector Robot Circuit Algorithm:
- Microcontroller based Metal Detector Robot Applications:
- Limitations of the Circuit:
Wireless Metal Detector Robot Circuit Principle:
The proposed system comprises two distinct circuits: one serving as the transmitter and the other as the receiver. The transmitter circuit is responsible for transmitting the instructions required for the robot’s operation. Meanwhile, the receiver circuit receives these instructions via radio frequency and directs the robot’s movements accordingly. Within the receiver circuit, a metal detector is linked to the controller. Consequently, whenever metal is detected, the robot ceases its movement, and a buzzer is activated, signaling the detection.
Wireless Metal Detector Robot Circuit Diagram:
Transmitter Circuit:
Receiver Circuit:
Circuit Components:
Hardware Components:
- AT89c51 microcontroller.
- RF encoder and decoder
- RF transmitter and receiver pair.
- Push buttons.
- Buzzer.
- Robot.
- L293d
- Rs 232 cable.
Software Components:
- Keil software
- Flash magic
- Proteus.
Circuit Design of Metal Detector Robot using Microcontroller:
The metal detection robot project can be segmented into two key sections: 1) The Transmitter section, and 2) The Receiver section.
The Transmitter component comprises an RF encoder, RF transmitter, and push buttons. In this application, we employ the HT12E RF encoder IC, an 18-pin integrated circuit. The encoder receives input through push buttons and converts it into a 4-bit binary format, which is then relayed in parallel to the RF emitter. This data is subsequently transmitted serially to the RF receiver. The address pins A0-A7, which are vital for secure transmission, are grounded in the transmitter circuit. The RF pair operates at a frequency of 434 kHz.
The Receiver section encompasses the AT89c51 microcontroller, RF decoder, RF receiver, metal detector, buzzer, L293d IC, and the robot itself.
The received data is channeled into the RF decoder, with the HT12D RF decoder IC being employed. The decoded inputs are connected to the microcontroller’s port 2, specifically, Port P2.0 – P2.3, corresponding to the four data pins D0-D3. The deciphered data is then processed by the microcontroller to control the robot’s movements. If any metal is detected along its path, the buzzer connected to port 3.4 is activated.
The metal detector, linked to the microcontroller’s pin 3.2, is a crucial component of the circuit. This detector features an oscillator, which generates an alternating magnetic field by passing an alternating current through a coil. When a metal object is in proximity to the coil, it creates a magnetic field disturbance, which can be detected using another coil designed to sense these changes.
Furthermore, the L293d IC, functioning as a motor driver, is employed to drive the motors within the robot. This IC incorporates an internal H-bridge for motor control. For more detailed information about this IC, please refer to the L293D Datasheet.
RF based Metal Detector Robot Circuit Simulation:
Wireless Metal Detection Robot Circuit Working:
- Initially burn the code into the microcontroller using flash magic.
- Now switch on the power supply for the circuit.
- Now send the command ‘1’ using the transmitter.
- This is transmitted to the receiver.
- At the receiver side receiver receives these commands and moves the robot according to the commands.
- The following commands moves the robot in the specified directions
- Forward
- Backward
- Left
- Right
- While robot is moving if any metal is detected in its path, the robot stops there ringing the buzzer.
- Again it starts moving when the commands are sent from the transmitter.
RF Based Metal Detection Robot Project Output Video:
Metal Detector Robot Circuit Algorithm:
- Initially, declare port2 as input as this is connected to the decoded input.
- Now declare port1 as output as the motor pins of the robot are connected to the port1.
- Enable the external interrupt.
- Now check the input of port2.
- If the received value is equal to 1 then move the robot in forward direction by making port value as 0x01.similarly move the robot according to the input value.
- When interrupt occurs make the output pins to the motor low. This is written in ISR.
Microcontroller based Metal Detector Robot Applications:
- These robots are used in detecting landmines.
- Robots are used for in detecting the minerals present in the ground.
- These robots are used for detecting the bombs.
- These can be used in construction industry for locating steel bars present in concrete.
- They are used in airports and building security to detect the weapons.
Limitations of the Circuit:
The transmitter can operate the robot only in the range of RF that is approximately 30 metres.
