# Use

Build a robot and drive into the world of robotics!

In this project we will guide you through building a Driving Base Robot and programming it to move straight and turn. You will also build and Object Detector Module, and program it to detect an object. It’s a good idea to have done the Try sequence first.

## Connect

What if your school had a multipurpose robot? How would you use it?

Would you use it to clean the school or plant trees?

## Build Your Driving Base Robot

Build the robot driving base:

If clicking the above image doesn’t open the instructions, right-click on the image and choose “Save link as…” to download the PDF.

## Make It Move

Code it: Create a program that makes the Driving Base move forward and stop at the finish line, which is `1` meter away.

Start by building this program:

``````brick.buttonEnter.onEvent(ButtonEvent.Pressed, function () {
motors.largeBC.steer(0, 50, 1, MoveUnit.Rotations)
})``````
• Drag a `||motors:steer large motors B+C||` block inside an `||brick:on button||` block.
• Click on the (+) sign.
• Change to `1` rotation.

Hint: You will have to modify the number of rotations until you find the number that matches the robot moving forward 1 meter and stopping.

## Make It Turn

Code it: Create a new program that turns the Driving Base 180 degrees.

``````brick.buttonEnter.onEvent(ButtonEvent.Pressed, function () {
motors.largeBC.steer(-50, 50, 1, MoveUnit.Rotations)
})``````

Hint: You will have to modify the turn ratio and the number of rotations until the robot reaches 180 degrees.

Build and attach an Ultrasonic Sensor to your driving base:

If clicking the above image doesn’t open the instructions, right-click on the image and choose “Save link as…” to download the PDF.

## Detect an Object

Code it: Create a program that moves the Driving Base and makes it stop `6` cm from the Cuboid.

Create a new program:

``````brick.buttonEnter.onEvent(ButtonEvent.Pressed, function () {
motors.largeBC.tank(50, 50)
sensors.ultrasonic4.setThreshold(UltrasonicSensorEvent.ObjectDetected, 6)
sensors.ultrasonic4.pauseUntil(UltrasonicSensorEvent.ObjectDetected);
motors.stopAll()
})``````
• Drag a `||motors:tank large motors B+C||` motor block inside the `||brick:on button||` block.
• Drag the Ultrasonic Sensor threshold `||sensors:set ultrasonic 4||` block and place it below the motor block.
• Drag a `|sensors:pause until ultrasonic 4||` block and place it under the threshold block.
• Drag a `||motors:stop all motors||` block and place it below the sensor block.

Hint: You will have to modify the values of the Ultrasonic Sensor block until the robot reaches the desired position.

``sensors.ultrasonic4.setThreshold(UltrasonicSensorEvent.ObjectDetected, 10)``