Learning C++, Arduino, and robotics for beginners - cross intersection in RCJ Line.

Line robot Overview Simplified assembly Standard assembly 1 Simplified installation Standard installation Standard Assembly 2 Hardware 1 Hardware 2 Skill Basic programming Line following Distance and color sensors Standard assembly 3 Gripper Program flow Advanced concepts For beginners Buy

Line Robot - Basic lessons - Exercises - Cross intersection

Another exercise inspired by RCJ Rescue Line.

Task: go over a crossing.

Make a full crossing on a white surface: stick 2 black stripes which intersect at 90°. The robot should follow a line, stop for 1 sec. on the crossing, then continue following the same stripe as before the crossing. The line-following code is here:

void RobotLine::loop() {
	if (line(5))
		go(10, 80);
	else if (line(3))
		go(80, 10);
	else
		go(60, 60);
}

Solution

void RobotLine::loop() {
	if (line(0) && line(8)){
		stop();
		delayMs(1000);
		go(50, 50);
		delayMs(500);
	}

	if (line(5))
		go(10, 80);
	else if (line(3))
		go(80, 10);
	else
		go(60, 60);
}

Remember that "&&" is logical "and". Second "if" - when both edge transistors find a black stripe, the robot is entering a crossing. Stop, wait 1 second, then go on for 500 ms, not minding the stripe below. 500 ms should be enough to exit the crossing. If not, change this parameter.

Index 8 denotes the last transistor in sensor. If You have MRMS reflectance sensors 8x, CAN, analog, I2C instead of MRMS reflectance sensors 9x, CAN, analog, I2C, the last index is 7.