This robotic might be managed with a smartphone utilizing Bluetooth by way of an Android app.
Its three sensors can measure 4 parameters: temperature, humidity, soil moisture, and ambient gentle depth in greenhouses, farms, gardens, parks, and so forth.
Often robots like robotic hand, agriculture robotic, fire-fighting robotic, spy robotic, snake robotic, humanoid, bomb (or mine) diffusing robotic function mechanically with none human intervention or are remote-controlled. Distant-controlled robots are principally wi-fi.
There are various kinds of wi-fi remote-controlled robots like:
- Hearth-fighting robots, that are used as fireplace extinguishers for spraying water or cardon-dioxide on fireplace.
- Bomb (mine) diffusing robots, that are used to diffuse dwell bombs or mines in a battlefield.
- Snake robots, which might enter small tunnels or pipelines for search and rescue operations or to seek out out any drawback like leakage in pipelines
This robotic screens the ambient parameters in a discipline. The operator can manoeuvre the robotic in a radius of 10 to 30 metres and take measurements to pick out one of the best place for plantation. And if plantation is already finished, the above-mentioned 4 parameters might be checked to see whether or not these are inside the threshold ranges or not for taking any corrective actions.
This venture might be modified for another purposes additionally by simply altering the sensors. For instance, by equipping the robotic with MQ2, MQ3 or related fuel sensors, it may be used to detect leakage of any fuel like cardon-dioxide, methane, or LPG.
Working
Earlier than constructing the robotic, allow us to first perceive its working by way of the system block diagram proven in Fig. 1 and the circuit diagram in Fig. 2. The main constructing blocks of the system embody the three sensors (soil moisture, DHT11 temperature and humidity sensor, and LDR), an Arduino Uno growth board, Bluetooth module HC-05, DC servo motor, two DC gear motors, and motor driver chip L293D. Allow us to first perceive the position of the key parts used within the venture.
Soil moisture sensor (SM1) is used to measure moisture content material in soil and provides analogue voltage output as per the moisture degree. Its output voltage decreases as moisture content material will increase.
DHT11 temperature and humidity sensor (SM2) is a great sensor that measures atmospheric temperature and humidity and offers direct digital values for temperature in °C and for humidity in % RH.
The sunshine dependant resistor (LDR1) is a photo-conductive machine whose resistance decreases as gentle depth will increase, and vice versa.
Bluetooth module (HC-05) is used to command (to maneuver ahead, reverse, left, and proper) the robotic from a smartphone with the assistance of Arduino Uno microcontroller.
The Arduino Uno board (Board1) performs following duties:
- Reads analogue output voltage from soil moisture sensor and converts it into digital worth. Then it calibrates it between 0 and 100% moisture degree
- Reads temperature and humidity values from DHT11 sensor
- Reads analogue voltage output from LDR1 and calibrates gentle depth between 0 and 100%
- Will get totally different instructions from Bluetooth module and rotates two DC motors to maneuver the robotic ahead, reverse, left, proper, or cease it.
- Sends (transmits) readings of all three sensors to Android smartphone by way of Bluetooth module
Motor driver L293D (IC1) supplies adequate voltage and present to each the motors to rotate them. It amplifies the output of Arduino board (Board1) and drives the motors.
The DC motors (M1 and M2) drive left and proper wheels of the robotic and transfer it ahead, backward, left, and proper.
Soil moisture sensor (SM1) is hooked up to servo motor (M3) shaft. This motor strikes the sensor up and all the way down to insert it into the soil to examine soil moisture content material.
HC-05 module operates on 5V obtained from the Arduino board. It communicates with Arduino board with USART pins Tx (D1) – Rx (D0). So, its Tx pin is related to Rx pin of Arduino board and vice versa.
DHT11 sensor additionally will get its 5V provide from Arduino board. Its digital output is related to digital pin D7 of Arduino.
The analogue output of soil moisture sensor (SM1) is related to analogue enter pin A1 of Arduino board. Its 5V provide additionally comes from Arduino board.
LDR1 is configured in pulled-down mode with 10-kilo-ohm pull-down resistor. Its analogue output is given to analogue enter pin A0 of Arduino board.
Digital pins D8, D9, D10, D11 of Arduino board drive DC motors M1 and M2 utilizing L293D chip. These pins are related to inputs of L293D, and two motors are related to output of the chip. Servo motor sign (sig) enter is related to PWM output pin D6 of Arduino board. The motor will get 5V provide from Arduino board.
The motor provide pin Vss of L293D (pin 8) will get 12V from battery. The Arduino board additionally will get 12V enter at its Vin pin from battery. That’s, Vin pin will get 12V enter and offers 5V output to all different parts.
Circuit and operation
The circuit operation begins when 12V battery is related to Arduino Uno board and L293D chip. Initially, each motors (M1 and M2) are at relaxation and so the robotic can be at relaxation. The servo motor (M3) is at 0° place and soil moisture sensor is in upward place.
To maneuver the robotic in any course, command is required from smartphone by way of Bluetooth based mostly Android utility, referred to as Bluetooth Terminal HC-05 by mightyIT. To do that, open (begin) Bluetooth Android utility in smartphone and seek for HC-05 Bluetooth module. As soon as the cellphone detects HC-05 module, pair it with the smartphone’s Bluetooth app. Enter passkey 1234 or 0000 the primary time to pair with HC-05 module.
Now you may ship instructions from the smartphone to robotic to maneuver utilizing the app. Following instructions given within the desk are used to maneuver the robotic (all these instructions are already set in Android utility):
When any of the above instructions is shipped (by sending the character in capital letter), it’s obtained by HC-05 module. The module additional offers this command to Arduino serially by way of its Tx-Rx pins. Arduino will get this command and compares it with set instructions. In the event that they match, the robotic strikes within the desired course.
As soon as robotic is in movement, it retains shifting (inside the vary) till command ‘S’ is shipped to cease it. When robotic stops, it strikes the servo motor by 90° in order that soil moisture sensor can go down into the soil to seize soil moisture worth. On the identical time, it begins studying sensor values from DHT11 and LDR. It reads analogue voltage output from soil moisture sensor and LDR and converts it to the vary of 0-100%. It additionally reads digital values of temperature and humidity from DHT11 sensor.
Robotic transmits all 4 values of those sensors to the smartphone by way of Bluetooth module. It retains transmitting these values each three seconds until it’s stopped by urgent ‘S’ command. When any of the instructions (F,B,R,L) is given, the corresponding servo motor strikes from 90° to 0° and the soil moisture sensor strikes up. The robotic stops transmitting sensor readings and begins shifting. Thus it offers an thought of ambient temperature, humidity, soil moisture, and lightweight depth within the space.
Operation of the circuit is managed by this system embedded in Arduino Uno microcontroller ATMega328.
Software program
This system code (BT_controlled_robot.ino) is written in Arduino programming language. It was examined utilizing Arduino IDE model 1.8.18. Earlier than compiling and importing the code, be sure you embody the related libraries, similar to DHT_sensor_library-1.4.2 and DHT sensor library model 1.4.3. Throughout testing it was discovered that with out these libraries the code couldn’t be compiled.
Obtain Supply Code
Building and testing
The circuit might be assembled on a breadboard or general-purpose PCB. The writer’s prototype is proven in Fig. 3. On connecting the circuit to a 12V DC provide, the onboard LED on Bluetooth HC-05 will begin blinking at a quick charge. Whenever you pair it efficiently along with your Bluetooth app in your cell phone, the LED will blink at a slower charge (two blinks per second). Open the Bluetooth Terminal HC-05 app from the cell phone, choose HC-05 once more.
If the whole lot’s nice, you may enter management instructions (F,B,R,L) within the app to maneuver the robotic. On getting into ‘S’ command, the robotic will cease and all of the sensor knowledge might be seen in your cell phone, as proven in Fig. 4.
Soil moisture sensor SM1 must be correctly fastened to the servo arm/horn utilizing both glue gun or screws. When servo motor pulls out soil moisture sensor from the soil, you may see the moisture degree drastically reduces to five, as proven in Fig. 5, indicating that the sensor is out of the soil.
Ashutosh M. Bhatt is M.Tech in embedded methods. At the moment, he’s lecturer of electronics and radio engineering at Authorities Polytechnic, Jamnagar, Gujarat
