WEBVTT 00:00.000 --> 00:05.580 Ever wondered how your phone screen adapts to sunlight by getting brighter and dimmer automatically? 00:05.580 --> 00:10.280 Or how greenhouses are just lighting to help plants grow better throughout the day? 00:10.280 --> 00:14.320 That's all possible thanks to light-seeking technology. 00:14.320 --> 00:15.560 Welcome! 00:15.560 --> 00:19.660 In this video, we'll build an Arduino light-seeking robot. 00:19.660 --> 00:22.000 Let's see how it's built. 00:23.000 --> 00:28.840 Let's start with the first and most important component of our project, the Arduino Uno Board. 00:29.080 --> 00:31.600 It is the brain of our project. 00:31.600 --> 00:39.560 Arduino is a microcontroller board that allows us to control and connect different electronic components like sensors, motors, etc. 00:39.560 --> 00:44.160 Our second component is the L298N motor driver. 00:44.160 --> 00:48.040 This component is used to control motors in our project. 00:48.040 --> 00:52.360 Our third component is two DC geared motors with two wheels. 00:52.360 --> 00:56.440 These motors are responsible for moving our robot. 00:56.600 --> 01:00.360 Our fourth component is the LDR sensor module. 01:00.360 --> 01:04.800 It helps the robot detect and follow the light. 01:04.800 --> 01:16.440 Our fifth component is the robot car chassis, along with other components used to mount parts like motors, the Arduino, battery, and sensors. 01:16.440 --> 01:22.560 There are several components are used like a battery to supply power, a rocker switch for control, 01:22.560 --> 01:26.240 and jumper wires to connect different parts of the robot. 01:26.240 --> 01:34.080 With all these components, along with some essential, we're going to build a light-seeking robot with Arduino. 01:34.080 --> 01:40.360 Let's understand the principles and real-world applications of light-seeking robot car. 01:40.360 --> 01:46.040 The robot follows light using its LDR sensors mounted at the front. 01:46.040 --> 01:54.120 Once light is detected, it begins to move, guided by the difference in light intensity between the left and right sensors. 01:54.160 --> 01:58.800 If the left sensor detects more light, then robot turns left. 01:58.800 --> 02:02.920 If the right sensor detects more light, then it turns right. 02:02.920 --> 02:09.160 And if both sensors detect equal light, the robot moves straight ahead following the light directly. 02:09.160 --> 02:16.720 This continuous comparison helps the robot chase the brightest light source, like a flashlight or sunlight. 02:16.720 --> 02:23.920 The Arduino processes the sensor data in real time, adjusting motor speeds for smooth, responsive steering, 02:23.920 --> 02:32.400 ensuring the robot continuously follows the light source or path without hesitation, even as conditions change. 02:32.400 --> 02:40.080 Light-seeking technology is used in solar panels that turn to face the sun so they can collect more energy during the day. 02:40.080 --> 02:45.840 It's also used in greenhouse automation systems, where lights or plant trays adjust their position, 02:45.840 --> 02:50.640 to ensure crops get the right amount of sunlight for better growth. 02:50.640 --> 02:57.840 Let's explore the core components of a light-seeking robot and understand the science behind them. 02:57.840 --> 03:00.960 The Arduino Uno is the brain of the robot. 03:00.960 --> 03:05.000 It receives input from sensors and sends output to motors. 03:05.000 --> 03:09.040 We upload code to control how the robot behaves. 03:09.040 --> 03:16.320 Technically, the Arduino Uno is a development board based on the AT-Mega3-2-8P microcontroller. 03:16.320 --> 03:25.680 It includes digital and analog eye-opens, a USB port for programming, a voltage regulator for stable 5 voltage power, 03:25.680 --> 03:30.600 a crystal oscillator for timing, and a reset button. 03:30.600 --> 03:37.760 It runs C and C++ code and controls sensors and motors in real time. 03:37.760 --> 03:42.760 This LDR sensor helps the robot detect light using changes in resistance, 03:42.760 --> 03:48.360 just like how automatic street lights turn on when it gets dark and turn off when it's bright. 03:48.360 --> 03:52.880 The LDR sensor responds to the brightness of surrounding light. 03:52.880 --> 03:58.920 As more light falls on it, the resistance decreases, allowing more current to flow. 03:58.920 --> 04:09.200 When there's less light, the resistance increases, and the current flows more slowly. 04:09.240 --> 04:14.160 The motor driver acts like a power manager between the Arduino and the motors. 04:14.160 --> 04:20.280 The Arduino sends control signals, but those signals aren't strong enough to run motors directly. 04:20.280 --> 04:25.880 So the motor driver boosts the control signals and sends them to the DC motors. 04:25.880 --> 04:35.440 The L298N motor driver includes the main L298N IC, which controls motor direction and power. 04:35.480 --> 04:39.240 It has terminal blocks for motor and power connections, 04:39.240 --> 04:45.840 input pins for signals from the Arduino, and enable pins for speed control. 04:45.840 --> 04:51.920 A built-in heat sink prevents the chip from overheating during operation. 04:51.920 --> 04:56.080 Let us program and test our light-seeking robot. 04:56.080 --> 05:00.200 Begin by assembling all the required components. 05:00.240 --> 05:07.040 We'll start by soldering wires to each of the motor terminals, one for positive and one for negative. 05:07.040 --> 05:14.480 Make sure the solder joints are strong and clean to avoid any loose connections during operation. 05:14.480 --> 05:18.480 Assemble the chassis by securely mounting DC motors in place, 05:18.480 --> 05:23.240 ensuring proper alignment for smooth movement of the robot. 05:23.240 --> 05:29.440 Then attach the third wheel to the chassis, using screws and brass spacers. 05:29.480 --> 05:35.640 Next, attach each wheel firmly to the shaft of the DC motors. 05:35.640 --> 05:40.120 Use screws or double-sided tape to securely attach the motor driver. 05:40.120 --> 05:45.400 Carefully mount the L298N motor driver onto the chassis. 05:45.400 --> 05:52.120 Choose a flat and central spot on the chassis to keep the wiring neat and balanced. 05:52.120 --> 05:57.080 Since we're using two motors, we'll connect one motor to each motor channel on the driver. 05:57.120 --> 06:01.360 Refer the circuit diagram and chart for connections. 06:01.360 --> 06:05.040 Now it's time to mount the Arduino board onto the chassis. 06:05.040 --> 06:11.760 Choose a central or rear area of the chassis where the board is safe and accessible for wiring. 06:11.760 --> 06:18.760 Now, connect the Arduino to the L298N motor driver by wiring the control pins. 06:18.760 --> 06:24.560 Connect ENA to digital pin 5 on the Arduino to enable speed control for the left motor. 06:24.560 --> 06:32.240 Then, connect IN1 and IN2 to pins D6 and D7 to control the direction of the left motor. 06:32.240 --> 06:39.680 Next, connect IN3 and IN4 to pins D8 and D9 for the right motor's direction. 06:39.680 --> 06:44.680 Finally, connect ENB to pin D10 to control the speed of the right motor. 06:44.680 --> 06:50.200 This setup, let the Arduino control both the direction and speed of the motors, 06:50.200 --> 06:54.400 using digital and PWM signals. 06:54.400 --> 06:59.360 Now, make the connections using jumper wires as shown in the circuit diagram, 06:59.360 --> 07:06.800 ensuring proper links between the LDR sensor, the servo motor and the Arduino board. 07:06.800 --> 07:12.600 Use a single red wire to supply VCC to both sensors, sharing the same power line. 07:12.600 --> 07:17.000 Then, connect a single black wire from the GND pins of both sensors. 07:17.000 --> 07:22.320 Next, connect a purple wire to the A-open of the right LDR sensor 07:22.320 --> 07:27.000 and a green wire to the A-open of the left LDR sensor. 07:27.000 --> 07:33.880 Now, attach the LDR sensors to the chassis, using double-sided tape to keep them secure. 07:33.880 --> 07:39.280 Next, attach the red VCC wire to the 5V pin on the Arduino 07:39.280 --> 07:43.600 and the black GND wire to one of the GND pins. 07:43.600 --> 07:49.120 Then, connect the green wire from the left LDR sensor to Arduino pin A1. 07:49.120 --> 07:54.280 Connect the purple wire from the right LDR sensor to Arduino pin A0. 07:54.280 --> 07:59.840 These connections allow the Arduino to read light levels from both sensors. 07:59.840 --> 08:05.120 Now, power the Arduino using the L298N motor driver. 08:05.120 --> 08:10.160 Connect the VIN pin of the Arduino to the 5V pin on the motor driver. 08:10.160 --> 08:17.080 Then, connect the GND pin of the Arduino to the GND pin on the motor driver. 08:17.120 --> 08:21.600 Mount the battery on the robot chassis to power the robot. 08:21.600 --> 08:27.720 We'll connect the battery using a switch button to the L298N motor driver. 08:27.720 --> 08:33.200 Connect the positive terminal of the battery to the VCC pin on the motor driver 08:33.200 --> 08:37.120 and the negative terminal to the GND pin. 08:37.120 --> 08:42.480 This will supply power to both the motors and the Arduino. 08:42.480 --> 08:45.000 Now that all the components are connected, 08:45.000 --> 08:51.800 our light-seeking robot is ready for programming and testing. 08:51.800 --> 08:56.680 Let us program and test our light-seeking robot. 08:56.680 --> 09:03.240 Connect the robots Arduino to the laptop using the Arduino USB cable. 09:03.240 --> 09:10.800 Open the Arduino IDE, then go to File, open and select your line following robot code. 09:10.800 --> 09:15.120 In the Tools menu, select Board and then Arduino Uno. 09:15.120 --> 09:20.080 Then, go to Port and select the correct COM port. 09:20.080 --> 09:24.720 Next, click the Verify button to check for any errors in the code. 09:24.720 --> 09:29.720 Once it's verified, click the Upload button to send the code to the Arduino. 09:29.720 --> 09:35.200 Finally, wait for the done uploading message to confirm the process is complete. 09:35.200 --> 09:41.240 Now, you can safely disconnect your laptop from the Arduino. 09:41.240 --> 09:45.840 Now, let's adjust the LDR sensors for accurate light detection, 09:45.840 --> 09:48.840 place the robot in a dark area, 09:48.840 --> 09:51.120 and use a torch to test the sensors, 09:51.120 --> 09:55.280 shine the torch on the right sensor, then the left. 09:55.280 --> 09:59.120 When light hits the sensor, both LEDs should turn on. 09:59.120 --> 10:01.160 Showing that light is detected, 10:01.160 --> 10:04.480 repeat to make sure both sensors respond properly. 10:04.480 --> 10:09.880 This helps the robot follow the brightest light accurately. 10:09.880 --> 10:13.000 Now, let's see the robot in action. 10:13.000 --> 10:16.560 Place it on a flat surface and turn on the switch. 10:16.560 --> 10:21.280 The robot stays still until light falls on its LDR sensors. 10:21.280 --> 10:25.120 As soon as it detects light, it begins to move toward the source. 10:25.120 --> 10:28.280 The sensors constantly compare light levels, 10:28.280 --> 10:31.920 and the robot adjusts its direction to follow the brightest path, 10:31.920 --> 10:35.280 all guided by simple sensors and smart logic.