Program the Viking Ship Robot

The Viking Ship Bot is programmed so that the left and right sensors check for objects. If they do, the bot will swing towards the object. If the Viking Ship Bot has swung back and forth for a hundred times, it will play a song!

This is the Viking Ship Bot’s pseudocode:

• Check the left and right sensors.
• If the left sensor senses an object, swing to the left.
• If the right sensor senses an object, swing to the right.
• If the Viking Ship Bot has swung a hundred times, play a melody.

The first thing you need to do is include the Smart Inventor library at the top of your code. Next, in void setup(), include your motors.

#include <SmartInventor.h>
 
void setup() {

 SmartInventor.DCMotorUse();

}

Next, set up variables for your left and right IR sensors, and use those variables in void setup() so the sensors will know if they’re seeing a value that isn’t normal. Add a buffer of 50 to leave some room for error.

#include <SmartInventor.h>

 
int baseLevelLeft = 0;
int baseLevelRight = 0;


 
void setup() {

  SmartInventor.DCMotorUse();

  baseLevelLeft = analogRead(19) - 50;
  baseLevelRight = analogRead(21) - 50;
}

In void loop(), set variables for each sensor so that they get and save the value that is being read from their corresponding pin.

#include <SmartInventor.h> 

int baseLevelLeft = 0;
int baseLevelRight = 0;

void setup() {

 SmartInventor.DCMotorUse();

 baseLevelLeft = analogRead(19) - 50;
 baseLevelRight = analogRead(21) - 50;
}

 void loop() {
 int leftSensor = analogRead(19);
 int rightSensor = analogRead(21);
}

Time for the main section of the code! You need to use an if statement to check if one of the sensors has detected an object.

Unlike the amusement park ride the Viking Ship Bot is modeled after, the Viking Ship Bot cannot swing up and around — it can only swing in the opposite direction of the last direction it went. To keep track of the last direction, you can create a variable named lastDirection in void setup() and then use it in void loop(). This will be updated when the code runs.

To count how many times the Viking Ship Bot has swung, create a variable named successCount, and then in void loop(), add += 1 to it. This will add 1 to the counter every time the bot swings back and forth.

#include <SmartInventor.h>

int baseLevelLeft = 0;
int baseLevelRight = 0;
int Right = 0;
int Left = 1;
int lastDirection = Right;
int successCount = 0;

void setup() {

  SmartInventor.DCMotorUse();

  baseLevelLeft = analogRead(19) - 50;
  baseLevelRight = analogRead(21) - 50;
}

 
void loop() {

  int leftSensor = analogRead(19);
  int rightSensor = analogRead(21);
 
  if(leftSensor < baseLevelLeft)
  {
    if(lastDirection == Right)
    {
      lastDirection = Left;
      SmartInventor.DCMotor(M1, CW, 100);
      delay(75);
      SmartInventor.DCMotor(M1, LOOSE, 0);
      successCount += 1;
    }
  }

  else if(rightSensor < baseLevelRight)
  {
    if(lastDirection == Left)
    {
      lastDirection = Right;
      SmartInventor.DCMotor(M1, CCW, 100);
      delay(75);
      SmartInventor.DCMotor(M1, LOOSE, 0);
      successCount += 1;
    }
  }

If the Viking Ship Bot has swung back and forth a hundred times, it will play a song! To do this, use the SmartInventor.Buzz command, which will play a note for a certain amount of time. We used 6 in our example, which means 1/6 of a second. You will also need to include a command to set your success count back to zero.

void loop() {

  int leftSensor = analogRead(19);
  int rightSensor = analogRead(21);
 
  if(leftSensor < baseLevelLeft)
  {
    if(lastDirection == Right)
    {
      lastDirection = Left;
      SmartInventor.DCMotor(M1, CW, 100);
      delay(75);
      SmartInventor.DCMotor(M1, LOOSE, 0);
      successCount += 1;
    }
  }

  else if(rightSensor < baseLevelRight)
  {
    if(lastDirection == Left)
    {
      lastDirection = Right;
      SmartInventor.DCMotor(M1, CCW, 100);
      delay(75);
      SmartInventor.DCMotor(M1, LOOSE, 0);
      successCount += 1;
    }
  }

  if(successCount > 100)
  {
    successCount = 0;
    SmartInventor.Buzz(NOTE_C5, 6);
    SmartInventor.Buzz(NOTE_E5, 6);
    SmartInventor.Buzz(NOTE_G5, 6);
  }
}

Your final code should look something like this:

#include <SmartInventor.h>

int baseLevelLeft = 0;
int baseLevelRight = 0;
int Right = 0;
int Left = 1;
int lastDirection = Right;
int successCount = 0;

void setup() {  
    SmartInventor.DCMotorUse();  
    
    baseLevelLeft = analogRead(19) - 50;  
    baseLevelRight = analogRead(21) - 50;
}

void loop() {  
    int leftSensor = analogRead(19);  
    int rightSensor = analogRead(21);   

    if(leftSensor < baseLevelLeft)  
    {    
        if(lastDirection == Right)    
        {      
            lastDirection = Left;      
        
            SmartInventor.DCMotor(M1, CW, 100);      
            delay(75);      
            SmartInventor.DCMotor(M1, LOOSE, 0);      

            successCount += 1;    
        }  
    }  

    else if(rightSensor < baseLevelRight)  
    {    
        if(lastDirection == Left)    
        {      
            lastDirection = Right;      

            SmartInventor.DCMotor(M1, CCW, 100);      
            delay(75);      
            SmartInventor.DCMotor(M1, LOOSE, 0);      

            successCount += 1;    
        }  
    }

  if(successCount > 100)
  {
    successCount = 0;
    SmartInventor.Buzz(NOTE_C5, 6);
    SmartInventor.Buzz(NOTE_E5, 6);
    SmartInventor.Buzz(NOTE_G5, 6);
  }
}

Still need help with the code or need to make sure your program is correct? Watch the video!