BreakingBot

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Let's see how our robot navigates. Several functions are available to make navigation possible:

• move_sonar(distance)
• move_distance_forward(distance)
• make_distance_backward(distance)
• turn_right()
• turn_left()
• u_turn()

and some others to grab the ball or drop it. Most of these functions do what their name implies. Here is what some of them do:

void move_sonar(distance){
//moves to the position where the value given by the ultrasonic sensor is distance +/- 5 mm
}
		
void move_distance_forward(distance){
//goes straight on for distance millimeters
}

void move_distance_backward(distance){
//back-pedals for distance millimeters
}

These functions are used both in the small arena and the big arena. Let's see how they are used in the small arena. Firstly as the beginner.

void beginner_going(){}
	//Starting in the beginner starting area, looking at the bottom wall.
	move_sonar(930)
	//goes back until the center of rotation of the robot is at half of the height of the arena
	turn_left()
	//turns left in order to be horizontal and looking at the closest wall
	move_sonar(436)
	//going backwards until the robot is close to the ball area
	u_turn()
	//turns around itself in order to have the claw located in the middle of the ball area
	drop_ball()
	//drops the ball in the ball area
	//sends BALL message to the server
	move_distance_backward(100)
	//goes a little bit backwards
	u_turn()
	//turn around itself in order to watch the wall on the right of the arena
	move_sonar(230)
	//goes closer to the wall
	turn_left()
	//turns left in order to be in front of its destination area
	move_sonar(230)
	//goes forward until it is in the destination area
	
	//sends NEXT message to the server
	//waits for a NEXT message from the teammate 
	if NEXT_message_received {
		beginner_return()	
	}
}

void beginner_return{
	move_sonar(810)
	//goes backward until being a little bit higher than the ball area
	turn_right()
	//turns right in order to be horizontal and looking at the closest wall
	move_sonar(710)
	//goes backward in order to arrive on the top-left corner of the ball area
	scan_right()
	//looks at the ball on its right and grabs it
	//sends BALL message to the server 
	//goes horizontally again
	move_sonar(230)
	//moves horizontally until being closed from the right wall
	turn_right()
	//turns right in order to be watching at the beginner starting area (its direction)
	move_sonar(230)
	//goes forward until it is in the starting area
	beginner_going()
	//starts again
}

Here is a short representation of the trajectory of the robot as a beginner - following the code above.

In case BreakingBot is the finisher, the pseudo-code is the one below. Note that "finisher_going" is like "beginner_return" but with a central symmetry. Likewise, "finisher_return" is like "beginner_going" with the same symmetry. :

void finisher_going(){
	move_sonar(810)
	//goes backward until being a little bit higher than the ball area
	turn_left()
	//turns left in order to be horizontal and looking at the closest wall
	move_sonar(710)
	//goes backward in order to arrive on the top-left corner of the ball area
	scan_left()
	//looks at the ball on its left and grabs it
	//sends BALL message to the server 
	//goes horizontally again
	move_sonar(230)
	//moves horizontally until being closed from the right wall
	turn_left()
	//turns left in order to be watching at the finisher destination area (its direction)
	move_sonar(230)
	//goes forward until it is in the destination area
	finisher_going()
	//starts again	
}

void finisher_return{
	move_sonar(930)
	//goes back until the center of rotation of the robot is at half of the height of the arena
	turn_right()
	//turns right in order to be horizontal and looking at the closest wall
	move_sonar(436)
	//going backwards until the robot is close to the ball area
	u_turn()
	//turns around itself in order to have the claw located in the middle of the ball area
	drop_ball()
	//drops the ball in the ball area
	//sends BALL message to the server
	move_distance_backward(100)
	//goes a little bit backwards
	u_turn()
	//turn around itself in order to watch the wall on the right of the arena
	move_sonar(230)
	//goes closer to the wall
	turn_right()
	//turns right in order to be in front of its starting area
	move_sonar(230)
	//goes forward until it is in the starting area
	//sends NEXT message to the server
	//waits for a NEXT message from the teammate 
	if NEXT_message_received{
		finisher_going()
	}
}