SupermanPrime01's profile - activity

Invoking "make cmake_check_build_system" failed Hello, I'm having a problem with catkin_make command in my workspace. T

Hello,

Is there a way I can take 60 values from a topic and calculate the average after every 60 values. I'm working with GPS and the accuracy is about 3 meters. So I'll get readings that are ~3 meters of where I'm actually at. Taking the average helps pin point my approximate location but I don't know a way to do it without copying and pasting my data into an excel sheet.

Thank you in advance.

How do I average 60 values published values from a node Hello, Is there a way I can take 60 values from a topic and cal

Hello,

So currently I have two GPS modules and they each have their own nodes. The 2 nodes publish their GPS information onto their own topics. So 2 nodes and 2 topics. I'm able to subscribe to both nodes but I'm having trouble using the variables in the callback function to calculate distance.

I would get this error: NameError: global name 'gps_lat' is not defined

Here's my code below

#!/usr/bin/env python
import rospy
from std_msgs.msg import String
from nmea_msgs.msg import Sentence
from sensor_msgs.msg import NavSatFix
import math

def callback(data):
    gps_lat = round(data.latitude, 6)
    gps_lon = round(data.longitude, 6)

def callback1(data):
    gps1_lat = round(data.latitude, 6)
    gps1_lon = round(data.longitude, 6)

def listener():

    rospy.init_node('gps_monitor', anonymous=True)
    rospy.Subscriber("/fix", NavSatFix, callback)
    rospy.Subscriber("/fix1", NavSatFix, callback1)
    rospy.spin()

    delta_lat = (gps_lat*(108000) - gps1_lat*(108000))
    delta_lon = (gps_lon*(108000) - gps1_lon*(108000))
    hyp_m = (delta_lat**2 + delta_lon**2)**0.5
    hyp_ft = (hyp_m*3.2800839)
    rospy.loginfo("Distance is %s in ft.", hyp_ft)



if __name__ == '__main__':
    listener()

Thank you so much Geoff. This was exactly what I needed. When I tried the global variables method the distances would co

How do I Calculate Distance Using 2 GPS Topics Hello, So currently I have two GPS modules and they each have their own

"libnmea_navsat_driver.driver1" then I went to the "nmea_navsat_driver/src/libnmea_navsat_driver.driver" folder to dupli

Sure thing. So what I did was I duplicated the file "nmea_serieal_driver" in the "nmea_navsat_driver/scripts" folder and

how to make multiple topics with nmea_navsat_driver Hello, I'm trying to figure out how to create 2 nodes and 2 topics

Thank you for providing the code. When people explain it to me, I have trouble visualizing it in my mind. Thankfully, you've provided the code and I can match the code with your description.

Hello,

I've gone through the turtlesim movement tutorials and they've helped a lot but I'm unable to get the script to continuously ask me for inputs for 1 minute and execute the movements. I've tried to use a while loop but it doesn't seem to work. When I Ctrl-C the terminal running the script it'll continuously ask me for inputs but the turtle doesn't move. How would I change the python code to have it asks me for inputs more than once and move the turtle multiple times without having to rerun the script?

The code I used is shown below:

#!/usr/bin/env python
import rospy
from geometry_msgs.msg import Twist
import time

def move():
    # Starts a new node
    rospy.init_node('robot_cleaner', anonymous=True)
    velocity_publisher = rospy.Publisher('/turtle1/cmd_vel', Twist, queue_size=10)
    vel_msg = Twist()

    #Receiveing the user's input
    print("Let's move your robot")
    speed = input("Input your speed:")
    distance = input("Type your distance:")
    isForward = input("Foward?: ")#True or False

    #Checking if the movement is forward or backwards
    if(isForward):
        vel_msg.linear.x = abs(speed)
    else:
        vel_msg.linear.x = -abs(speed)
    #Since we are moving just in x-axis
    vel_msg.linear.y = 0
    vel_msg.linear.z = 0
    vel_msg.angular.x = 0
    vel_msg.angular.y = 0
    vel_msg.angular.z = 0

    while not rospy.is_shutdown():

        #Setting the current time for distance calculus
        t0 = rospy.Time.now().to_sec()
        current_distance = 0

        #Loop to move the turtle in an specified distance
        while(current_distance < distance):
            #Publish the velocity
            velocity_publisher.publish(vel_msg)
            #Takes actual time to velocity calculus
            t1=rospy.Time.now().to_sec()
            #Calculates distancePoseStamped
            current_distance= speed*(t1-t0)
        #After the loop, stops the robot
        vel_msg.linear.x = 0
        #Force the robot to stop
        velocity_publisher.publish(vel_msg)


if __name__ == '__main__':
     try:
         timeout =  time.time() + 60
         while time.time() < timeout:
             move()

     except rospy.ROSInterruptException:
         pass