 Hello everyone, in this video we are going to program a two-wheel drive RD-No-No robot using the Pictoblox application. The robot should move forward on pressing the up arrow key, it should turn left on pressing the left arrow key, it should turn right on pressing the right arrow key and it should come backward on pressing the down arrow key. Before we begin let's understand the anatomy of the robot. The robot has a chassis upon which the entire body is built, two DC motors with wheels attached to make it move, a castor wheel, a battery to power it up, a motor driver IC and an RD-No-No board that acts as the brain of the robot. Now let's have a look at its connections. The right motor's direction pins are connected to Uno's digital pin 4 and 5 and the enable pin to Uno's PWM pin 6. Similarly the left motor's direction pins are connected to Uno's digital pin 9 and 10 and its enable pin to Uno's PWM pin 11. Bluetooth module's ground is connected to Uno's ground plus 5 volt to Uno's plus 5 volt RX pin to Uno's digital pin 1 and TX to Uno's digital pin 0. To get the detailed instruction of the making, go to the link given in the description box. For now let's understand briefly how the robot will move. If we rotate both the wheels in the forward direction, the robot will go forward. If we rotate both the wheels in the reverse direction, the robot will go backward. If we rotate the left wheel in the reverse direction and the right wheel in the forward direction, then it should turn left. Similarly, if we rotate the right wheel in the reverse direction and the left wheel in the forward direction, then the robot should turn right. To program the RD-No-No board in the app and to control it in real time, it must have firmware uploaded to it. Let's upload the firmware using the PictoBlock stickstop version. Open PictoBlock on your computer. Connect the Uno board to it using a USB cable. Click on the board button and select Arduino Uno from the drop-down. Next, click the connect button and select the appropriate serial port. Then click the upload firmware button. Note that uploading the firmware is a one-time process. To connect the robot to the app, we'll need a Bluetooth module. We have our Bluetooth module already connected to Arduino Uno. Now open the app. Go to MySpace and tap the plus button to start a new program. Next, tap the board icon and select Arduino Uno from the list. Next, tap the connect icon. A list of nearby Bluetooth devices will appear. Select your Bluetooth module from the list. Now let's create the script to control our robot. From the actuators palette, drag and drop a connect motor block to define the pins to which the motors are connected. Define both the motors. Next, drag and drop an if-else block from the control palette below the connect motor block. To sense whether the up arrow keys pressed or not, drag and drop a key pressed block from the sensing palette. If the condition is true, the robot should move forward, that is, both the motors should rotate in the forward direction. Thus, from the actuator palette, drag and drop a run motor block and place it below the if-arm of the if-else block. Add another run motor block and select motor 2 from the drop-down. If the down key is pressed, the robot should move backward. Thus, duplicate the above two motor blocks and select reverse from the direction drop-down in both the blocks. Similarly, on pressing the right key, the robot should turn right. For that, motor 1 should rotate in the forward direction and motor 2 should rotate in the reverse direction. Finally, on pressing left, it should turn left. For that, motor 1 should rotate in the reverse direction and motor 2 should rotate in the forward direction. And if none of the keys are pressed, the robot should stop moving or stay at rest if not already moving. For that, drag and drop a free motor block for both the motors and place them under the if-else block. Now, to execute these actions continuously, drag and drop a forever block around the entire if-else tree. Finally, to trigger the script, drag and drop a well-flag-clicked hat block above the entire script. Now go to the stage, tap the green flag to start the script and use the arrow keys to control your robot. If the robot is not moving according to the actions assigned, then interchange the connections of the motor that is malfunctioning. That's it for this video. If you liked it, give it a thumbs up and share it with your friends. For more such educational videos, subscribe to Stempedia and follow us on Facebook, Instagram and Twitter. Bye!