Mission

Mission: Let's solve the password and reach the goal point!

- This mission is an team project

- Move the robot to the desired point through a combination of simple numbers.

- There may even be a reward if you arrive correctly!

How to Play

• Arrive at the goal point by freely moving the robot through a combination of numbers from 0 to 9.

• To move the robot, we use Python functions.

  • First, import the required Python modules.

  import rospy
  import json
  from std_msgs.msg import UInt8MultiArray, String
  from nav_msgs.msg import Odometry
  import time
  import math
  

  • Create nodes and publishers to deliver messages to robots using ROS.

  pub = rospy.Publisher('/robot_command', String, queue_size=1)
  rospy.init_node('zetabot', anonymous=True)
  time.sleep(1)
  

  • Write a function that goes forward by 1.

  def move_forward_1():
  tmp = {"MoveDelta": 1}
  msg = json.dumps(tmp)
  rospy.loginfo("Sent: %s", msg)
  pub.publish(msg)
  

  • Write a function that goes forward by 2.

  def move_forward_2():
  tmp = {"MoveDelta": 2}
  msg = json.dumps(tmp)
  rospy.loginfo("Sent: %s", msg)
  pub.publish(msg)
  

  • Write a function that goes backward by 1.

  def move_backward_1():
  tmp = {"MoveDelta": -1}
  msg = json.dumps(tmp)
  rospy.loginfo("Sent: %s", msg)
  pub.publish(msg)
  

  • Write a function that goes backward by 2.

  def move_backward_2():
  tmp = {"MoveDelta": -2}
  msg = json.dumps(tmp)
  rospy.loginfo("Sent: %s", msg)
  pub.publish(msg)
  

  • Write a function that turns 45 degrees to the right.

  def turn_right_45():
  tmp = {"TurnDelta": math.radians(int(-45))}
  msg = json.dumps(tmp)
  rospy.loginfo("Sent: %s", msg)
  pub.publish(msg)
  

  • Write a function that turns 90 degrees to the right.

  def turn_right_90():
  tmp = {"TurnDelta": math.radians(int(-90))}
  msg = json.dumps(tmp)
  rospy.loginfo("Sent: %s", msg)
  pub.publish(msg)
  

  • Write a function that turns 45 degrees to the left.

  def turn_left_45():
  tmp = {"TurnDelta": math.radians(int(45))}
  msg = json.dumps(tmp)
  rospy.loginfo("Sent: %s", msg)
  pub.publish(msg)
  

  • Write a function that turns 90 degrees to the left.

  def turn_left_90():
  tmp = {"TurnDelta": math.radians(int(90))}
  msg = json.dumps(tmp)
  rospy.loginfo("Sent: %s", msg)
  pub.publish(msg)
  

  • Write a function that turns 180 degrees to the left.

  def spin():
  tmp = {"TurnDelta": math.radians(int(180))}
  msg = json.dumps(tmp)
  rospy.loginfo("Sent: %s", msg)
  pub.publish(msg)
  

  • Write a function that stops in place.

  def stop():
  tmp = {"Stop": 0}
  msg = json.dumps(tmp)
  rospy.loginfo("Sent: %s", msg)
  pub.publish(msg)
  

Let’s Find the Right Password!

• Talk about how to enter your password.

• This code allows Jupyterhub to accept numeric input.

user_input = str(input("Password : "))

• After executing the cell by pressing “Shift + Enter”, enter a number and press “Enter” to save the password.

• The robot moves differently depending on the password, which is a combination of entered numbers.

for char in user_input:
    if char == "1":
        move_forward_1()
        time.sleep(4)
    elif char == "2":
        move_forward_2()
        time.sleep(8)
    elif char == "3":
        move_backward_1()
        time.sleep(4)
    elif char == "4":
        move_backward_2()
        time.sleep(8)
    elif char == "5":
        turn_left_45()
        time.sleep(3)
    elif char == "6":
        turn_left_90()
        time.sleep(6)
    elif char == "7":
        turn_right_45()
        time.sleep(3)
    elif char == "8":
        turn_right_90()
        time.sleep(6)
    elif char == "9":
        spin()
        time.sleep(12)
    elif char == "0":
        stop()
        time.sleep(1)
    else:
        print("Invalid input:", char)

• If you put in 1, it goes forward by 1, if you put in 2, it goes forward by 2.

• If you put in 3, it goes backwards by 1, if you put in 4, it goes backward by 2.

• If you put in 5, it goes 45 degrees to the left, and if you put in 6, it goes 90 degrees to the left.

• If you put in 7, it goes 45 degrees to the right, and if you put in 8, it goes 90 degrees to the right.

• If you put 9, it will rotate 180 degrees, if you put 0, it will stop in place.

• For example, if you enter the password “1290”, The robot will move in the following order: forward 1, forward 2, turn 180 degrees, and stop.

• Now, let’s make the robot arrive by entering the password suitable for the destination!