Services_quiz - ros in 5 days

Course Support ROS Basics In 5 Days (Python)
1

Hello,

Please can someone help me look through this code? I have been up till 3am but I still can’t move the robot using the side and repetitions correctly. I have checked the similar questions asked but still no progress. I have tried various methods and this is my code at the moment, thank you.

Service_server
#! /usr/bin/env python

import rospy

from services_quiz.srv import BB8CustomServiceMessage, BB8CustomServiceMessageResponse

from geometry_msgs.msg import Twist

def my_callback(request):

rospy.loginfo("The service bb8 has been called")



j = 0

while j < request.repetitions:

    if request.side == 1.0:

        i = 0

        while(i < 4.0):

            rospy.loginfo("running square")

            move_square.linear.x = size

            pub.publish(move_square)

            rospy.Rate.sleep()

            move_square.linear.x = 0.0

            pub.publish(move_square)

            rospy.Rate.sleep()

            move_square.angular.z = 0.9

            pub.publish(move_square)

            rospy.Rate.sleep()

            move_square.angular.z = 0.0

            pub.publish(move_square)

            rospy.Rate.sleep()

            

        i+=1

    elif request.side == 2.0:

        i = 0

        while(i < 4.0):

            rospy.loginfo("running square")
            move_square.linear.x = size

            pub.publish(move_square)

            rospy.Rate.sleep()

            move_square.linear.x = 0.0

            pub.publish(move_square)

            rospy.Rate.sleep()

            move_square.angular.z = 0.9

            pub.publish(move_square)

            rospy.Rate.sleep()

            move_square.angular.z = 0.0

            pub.publish(move_square)

            rospy.Rate.sleep()

            

        i+=1

          

j+=1



move_square.linear.x = 0.0

move_square.angular.z = 0.0

pub.publish(move_square)

rospy.loginfo("Finished first small square ")

        

my_response = BB8CustomServiceMessageResponse()

my_response.success = True
return my_response

rospy.init_node(‘service_move_bb8_in_square_custom_server’)

my_service = rospy.Service(’/move_bb8_in_square_custom’, BB8CustomServiceMessage, my_callback)

pub = rospy.Publisher(’/cmd_vel’, Twist, queue_size=1)

move_square = Twist()

rate = rospy.Rate(1)

rospy.loginfo(“The service /move_bb8_in_square_custom is ready”)

rospy.spin()

Service_client
#! /usr/bin/env python

import rospkg

import rospy

from services_quiz.srv import BB8CustomServiceMessage, BB8CustomServiceMessageRequest

rospy.init_node(‘service_move_bb8_in_square_custom_client’)

rospy.wait_for_service(’/move_bb8_in_square_custom’)

move_bb8_in_square_service_client = rospy.ServiceProxy(’/move_bb8_in_square_custom’, BB8CustomServiceMessage)

move_bb8_in_square_object = BB8CustomServiceMessageRequest()

move_bb8_in_square_object.repetitions = 2

i = 0

while i < move_bb8_in_square_object.repetitions:

if i ==0:

    move_bb8_in_square_object.side = 1.0

elif i ==1:

   move_bb8_in_square_object.side = 2.0

i+=1

rospy.loginfo(“Doing service call”)

result = move_bb8_in_square_service_client(move_bb8_in_square_object)

rospy.loginfo(str(result))

rospy.loginfo(“End of Service call…”)

2

Can you be more specific? Is there an error message in the command line when you run your code?

3

Hello @diego98cs,

Thank you for your response. There was no error message. On the server client side, the cursor just blinks and the robot doesnt move. I am back to working on it this morning. Any help would be appreciated, thanks.

4

Hello,

I was able to solve the quiz on my own, thank you!

1 Like