hey everyone,

i am trying to let my jackal drive with this custom node :

#! /usr/bin/env python

import rospy
from geometry_msgs.msg import Twist
from sensor_msgs.msg import LaserScan


def callback(msg):
seconds = rospy.get_time()
if int(seconds) % 3 == 0:
    move.linear.x = 0
    move.linear.y = 1
    move.angular.z = 0
elif int(seconds+1) % 3 == 0: 
    move.linear.x = 0
    move.angular.z = -0
else:
    move.linear.x = -2
    move.angular.z = -2

pub.publish(move)

rospy.init_node('sub_node')
sub = rospy.Subscriber('/kobuki/laser/scan', LaserScan, callback)
pub = rospy.Publisher('/cmd_vel',Twist,queue_size=10)
move = Twist()

rospy.spin()

however it returns the error : /clock not being published etc. you probably know the error.

but /clock definetely is running, and my jackal isnt moving. rostopic info /cmd_vel does state its subscribing the node i want. maybe its worth it to state that this script DOES work with the turtlebot in gazebo.

greetings girpon