updated code for ROS Noetic package

README.md

@@ -1,4 +1,22 @@
-# ros_essentials_cpp
-This repository contains the code needed for the Udemy course entitled
-ROS For Beginners: Basics, Motion and OpenCV
-https://www.udemy.com/ros-essentials/
+# ROS For Beginners: Basics, Motion, and OpenCV - Udemy Course (ROS Noetic Version)
+
+This repository contains the source code and materials for the Udemy course **ROS For Beginners: Basics, Motion, and OpenCV**. Learn the fundamentals of the Robot Operating System (ROS) and gain practical experience in robot motion and perception using OpenCV.
+
+[![Course](https://img.shields.io/badge/Udemy-Course-blue)](https://www.udemy.com/ros-essentials/)
+[![Discount](https://img.shields.io/badge/Discount-Coupons-green)](https://www.riotu-lab.org/udemy.php)
+
+## Package: Assignment
+
+- **topic01_basics**: ROS Basics and Foundation - Learn essential ROS concepts, such as topics, services, messages, and nodes.
+- **topic02_motion**: Motion in ROS - Apply the concepts from the basics section to control robot motion and develop various trajectories using a cleaning robot simulation.
+- **topic03_perception**: Perception in ROS - Discover how a robot perceives its environment using a camera, and how images are collected in ROS and processed in OpenCV.
+- **topic04_perception02_laser**: Arduino Integration - Learn how to use Arduino boards and sensors with ROS using the ROSSERIAL Arduino interface, enabling integration with various Arduino sensors and boards.
+
+### ROS Noetic and OpenCV4
+
+This repository is updated for ROS Noetic, which uses OpenCV4. There are some differences between OpenCV4 and the previous versions (OpenCV3) used in ROS Melodic and Kinetic. The code in this repository has been updated to compile seamlessly on a fresh installation of ROS Noetic.
+
+## Enroll in the Course
+
+To enroll in the Udemy course, visit [ROS For Beginners: Basics, Motion and OpenCV](https://www.udemy.com/ros-essentials/). 
+For discount coupons, check [https://www.riotu-lab.org/udemy.php](https://www.riotu-lab.org/udemy.php).

include/readme

@@ -0,0 +1 @@
+Noetic version

src/topic01_basics/service/add_client.py

@@ -12,19 +12,19 @@ def add_two_ints_client(x, y):
         add_two_ints = rospy.ServiceProxy('add_two_ints', AddTwoInts)
         resp1 = add_two_ints(x, y)
         return resp1.sum
-    except rospy.ServiceException, e:
-        print "Service call failed: %s"%e
+    except rospy.ServiceException(e):
+        print ("Service call failed: %s"%e)
 
 def usage():
-    return "%s [x y]"%sys.argv[0]
+    return 
 
 if __name__ == "__main__":
     if len(sys.argv) == 3:
         x = int(sys.argv[1])
         y = int(sys.argv[2])
     else:
-        print usage()
+        print ("%s [x y]"%sys.argv[0])
         sys.exit(1)
-    print "Requesting %s+%s"%(x, y)
+    print ("Requesting %s+%s"%(x, y))
     s = add_two_ints_client(x, y)
-    print "%s + %s = %s"%(x, y, s)
+    print ("%s + %s = %s"%(x, y, s))

src/topic01_basics/service/add_server.py

@@ -7,14 +7,14 @@
 import rospy
 
 def handle_add_two_ints(req):
-    print "Returning [%s + %s = %s]"%(req.a, req.b, (req.a + req.b))
+    print ("Returning [%s + %s = %s]"%(req.a, req.b, (req.a + req.b)))
     return AddTwoIntsResponse(req.a + req.b)
 
 def add_two_ints_server():
     rospy.init_node('add_two_ints_server')
     s = rospy.Service('add_two_ints', AddTwoInts, handle_add_two_ints)
-    print "Ready to add two ints."
+    print ("Ready to add two ints.")
     rospy.spin()
 
 if __name__ == "__main__":
-    add_two_ints_server()
+    add_two_ints_server()

src/topic02_motion/turtlesim/clean.launch

@@ -0,0 +1,8 @@
+
+
+<launch>
+  <node name="turtlesim" pkg="turtlesim" type="turtlesim_node" />
+  <node name="clean_node" pkg="ros_essentials_cpp" type="turtlesim_cleaner.py" />
+</launch>
+
+

src/topic02_motion/turtlesim/robot_cleaner.cpp

@@ -32,7 +32,7 @@ void setDesiredOrientation (double desired_angle_radians);
 void poseCallback(const turtlesim::Pose::ConstPtr & pose_message);
 void moveGoal(turtlesim::Pose  goal_pose, double distance_tolerance);
 void gridClean();
-void spiralClean();
+void spiralClean(double rk, double wk);
 
 int main(int argc, char **argv)
 {
@@ -47,62 +47,13 @@ int main(int argc, char **argv)
 	velocity_publisher = n.advertise<geometry_msgs::Twist>("/turtle1/cmd_vel", 1000);
 	pose_subscriber = n.subscribe("/turtle1/pose", 10, poseCallback);
 
-	//ros::Rate loop_rate(10);
-
-
-
 	/** test your code here **/
 	ROS_INFO("\n\n\n******START TESTING************\n");
-	/*cout<<"enter speed: ";
-	cin>>speed;
-	cout<<"enter distance: ";
-	cin>>distance;
-	cout<<"forward?: ";
-	cin>>isForward;
-	move(speed, distance, isForward);
-
-	cout<<"enter angular velocity (degree/sec): ";
-	cin>>angular_speed;
-	cout<<"enter desired angle (degrees): ";
-	cin>>angle;
-	cout<<"clockwise ?: ";
-	cin>>clockwise;
-	rotate(degrees2radians(angular_speed), degrees2radians(angle), clockwise);
-	 */
 	ros::Rate loop_rate(0.5);
-	/*setDesiredOrientation(degrees2radians(120));
-
-	loop_rate.sleep();
-	setDesiredOrientation(degrees2radians(-60));
-	loop_rate.sleep();
-	setDesiredOrientation(degrees2radians(0));*/
-
-	/*turtlesim::Pose goal_pose;
-	goal_pose.x=1;
-	goal_pose.y=1;
-	goal_pose.theta=0;
-	moveGoal(goal_pose, 0.01);
-	loop_rate.sleep();
-	 */
-
 	//gridClean();
+	//loop.sleep();
 
-	ros::Rate loop(0.5);
-	turtlesim::Pose pose;
-	pose.x=1;
-	pose.y=1;
-	pose.theta=0;
-	moveGoal(pose, 0.01);
-
-	pose.x=6;
-	pose.y=6;
-	pose.theta=0;
-	moveGoal(pose, 0.01);
-
-
-
-	loop.sleep();
-	//spiralClean();
+	spiralClean(0,4);
 
 	ros::spin();
 
@@ -276,36 +227,23 @@ void gridClean(){
 }
 
 
-void spiralClean(){
+void spiralClean(double rk, double wk){
 	geometry_msgs::Twist vel_msg;
-	double count =0;
 
-	double constant_speed=4;
-	double vk = 1;
-	double wk = 2;
-	double rk = 0.5;
 	ros::Rate loop(1);
 
 	do{
 		rk=rk+1.0;
 		vel_msg.linear.x =rk;
-		vel_msg.linear.y =0;
-		vel_msg.linear.z =0;
-		//set a random angular velocity in the y-axis
-		vel_msg.angular.x = 0;
-		vel_msg.angular.y = 0;
-		vel_msg.angular.z =constant_speed;//((vk)/(0.5+rk));
+		vel_msg.angular.z =wk;
 
 		cout<<"vel_msg.linear.x = "<<vel_msg.linear.x<<endl;
 		cout<<"vel_msg.angular.z = "<<vel_msg.angular.z<<endl;
 		velocity_publisher.publish(vel_msg);
 		ros::spinOnce();
 
 		loop.sleep();
-		//vk = vel_msg.linear.x;
-		//wk = vel_msg.angular.z;
-		//rk = vk/wk;
-		cout<<rk<<", "<<vk <<", "<<wk<<endl;
+
 	}while((turtlesim_pose.x<10.5)&&(turtlesim_pose.y<10.5));
 	vel_msg.linear.x =0;
 	velocity_publisher.publish(vel_msg);

src/topic02_motion/turtlesim/turtlesim_cleaner.py

@@ -7,10 +7,6 @@
 import time
 from std_srvs.srv import Empty
 
-x=0
-y=0
-yaw=0
-
 def poseCallback(pose_message):
     global x
     global y, yaw
@@ -24,7 +20,7 @@ def poseCallback(pose_message):
     #print ('yaw = {}'.format(pose_message.theta)) #new in python 3
 
 
-def move(speed, distance, is_forward):
+def move(velocity_publisher, speed, distance, is_forward):
         #declare a Twist message to send velocity commands
         velocity_message = Twist()
         #get current location 
@@ -39,19 +35,16 @@ def move(speed, distance, is_forward):
 
         distance_moved = 0.0
         loop_rate = rospy.Rate(10) # we publish the velocity at 10 Hz (10 times a second)    
-        cmd_vel_topic='/turtle1/cmd_vel'
-        velocity_publisher = rospy.Publisher(cmd_vel_topic, Twist, queue_size=10)
-
+
         while True :
                 rospy.loginfo("Turtlesim moves forwards")
                 velocity_publisher.publish(velocity_message)
 
                 loop_rate.sleep()
 
-                #rospy.Duration(1.0)
-
-                distance_moved = abs(0.5 * math.sqrt(((x-x0) ** 2) + ((y-y0) ** 2)))
-                print  distance_moved               
+                distance_moved = abs(math.sqrt(((x-x0) ** 2) + ((y-y0) ** 2)))
+                print  (distance_moved)
+                print(x)
                 if  not (distance_moved<distance):
                     rospy.loginfo("reached")
                     break
@@ -60,19 +53,10 @@ def move(speed, distance, is_forward):
         velocity_message.linear.x =0
         velocity_publisher.publish(velocity_message)
 
-def rotate (angular_speed_degree, relative_angle_degree, clockwise):
+def rotate (velocity_publisher, angular_speed_degree, relative_angle_degree, clockwise):
 
-    global yaw
     velocity_message = Twist()
-    velocity_message.linear.x=0
-    velocity_message.linear.y=0
-    velocity_message.linear.z=0
-    velocity_message.angular.x=0
-    velocity_message.angular.y=0
-    velocity_message.angular.z=0
-
-    #get current location 
-    theta0=yaw
+
     angular_speed=math.radians(abs(angular_speed_degree))
 
     if (clockwise):
@@ -106,20 +90,18 @@ def rotate (angular_speed_degree, relative_angle_degree, clockwise):
     velocity_publisher.publish(velocity_message)
 
 
-def go_to_goal(x_goal, y_goal):
+def go_to_goal(velocity_publisher, x_goal, y_goal):
     global x
     global y, yaw
 
     velocity_message = Twist()
-    cmd_vel_topic='/turtle1/cmd_vel'
 
     while (True):
         K_linear = 0.5 
         distance = abs(math.sqrt(((x_goal-x) ** 2) + ((y_goal-y) ** 2)))
 
         linear_speed = distance * K_linear
 
-
         K_angular = 4.0
         desired_angle_goal = math.atan2(y_goal-y, x_goal-x)
         angular_speed = (desired_angle_goal-yaw)*K_angular
@@ -128,57 +110,51 @@ def go_to_goal(x_goal, y_goal):
         velocity_message.angular.z = angular_speed
 
         velocity_publisher.publish(velocity_message)
-
-        #print velocity_message.linear.x
-        #print velocity_message.angular.z
-        print 'x=', x, 'y=',y
-
+        print ('x=', x, ', y=',y, ', distance to goal: ', distance)
 
         if (distance <0.01):
             break
 
-def setDesiredOrientation(desired_angle_radians):
-    relative_angle_radians = desired_angle_radians - yaw
+def setDesiredOrientation(publisher, speed_in_degree, desired_angle_degree):
+    relative_angle_radians = math.radians(desired_angle_degree) - yaw
+    clockwise=0
     if relative_angle_radians < 0:
         clockwise = 1
     else:
         clockwise = 0
-    print relative_angle_radians
-    print desired_angle_radians
-    rotate(30 ,math.degrees(abs(relative_angle_radians)), clockwise)
+    print ("relative_angle_radians: ",math.degrees(relative_angle_radians))
+    print ("desired_angle_degree: ",desired_angle_degree)
+    rotate(publisher, speed_in_degree,math.degrees(abs(relative_angle_radians)), clockwise)
 
-def gridClean():
+def gridClean(publisher):
 
     desired_pose = Pose()
     desired_pose.x = 1
     desired_pose.y = 1
     desired_pose.theta = 0
 
-    moveGoal(desired_pose, 0.01)
+    go_to_goal(publisher, 1,1)
 
-    setDesiredOrientation(degrees2radians(desired_pose.theta))
+    setDesiredOrientation(publisher, 30, math.radians(desired_pose.theta))
 
-    move(2.0, 9.0, True)
-    rotate(degrees2radians(20), degrees2radians(90), False)
-    move(2.0, 9.0, True)
-    rotate(degrees2radians(20), degrees2radians(90), False)
-    move(2.0, 1.0, True)
-    rotate(degrees2radians(20), degrees2radians(90), False)
-    move(2.0, 9.0, True)
-    rotate(degrees2radians(30), degrees2radians(90), True)
-    move(2.0, 1.0, True)
-    rotate(degrees2radians(30), degrees2radians(90), True)
-    move(2.0, 9.0, True)
+    for i in range(5):
+        move(publisher, 2.0, 1.0, True)
+        rotate(publisher, 20, 90, False)
+        move(publisher, 2.0, 9.0, True)
+        rotate(publisher, 20, 90, True)
+        move(publisher, 2.0, 1.0, True)
+        rotate(publisher, 20, 90, True)
+        move(publisher, 2.0, 9.0, True)
+        rotate(publisher, 20, 90, False)
     pass
+
 
 
-def spiralClean():
+def spiralClean(velocity_publisher, wk, rk):
     vel_msg = Twist()
     loop_rate = rospy.Rate(1)
-    wk = 4
-    rk = 0
 
-    while((currentTurtlesimPose.x<10.5) and (currentTurtlesimPose.y<10.5)):
+    while((x<10.5) and (y<10.5)):
         rk=rk+1
         vel_msg.linear.x =rk
         vel_msg.linear.y =0
@@ -208,10 +184,11 @@ def spiralClean():
         pose_subscriber = rospy.Subscriber(position_topic, Pose, poseCallback) 
         time.sleep(2)
 
-        #move(1.0, 2.0, False)
-        #rotate(30, 90, True)
-        go_to_goal(1.0, 1.0)
-        #setDesiredOrientation(math.radians(90))
-
+        #move(velocity_publisher, 1.0, 9.0, True)
+        #rotate(velocity_publisher, 30, 90, True)
+        #go_to_goal(velocity_publisher, 2.0, 1.5)
+        #setDesiredOrientation(velocity_publisher, 30, 90)
+        #spiralClean(velocity_publisher, 4, 0)
+        gridClean(velocity_publisher)
     except rospy.ROSInterruptException:
-        rospy.loginfo("node terminated.")
+        rospy.loginfo("node terminated.")