Retrieve velocity data from twist messages
Hello I would like to inspect and pass on the individual velocities from Twist messages, are there methods to do this? Thanks.
Hello I would like to inspect and pass on the individual velocities from Twist messages, are there methods to do this? Thanks.
hi, you probably want to do something like this (this is an example that converts geometry_msgs/Twist message to turtlesim/Velocity message):
def TwistToTurtle(): #initialization
rospy.init_node('TwistToTurtle',anonymous=False)
rospy.Subscriber('cmd_vel',Twist,gotTwistCB) #subscribe to cmd_vel topic which publishes Twist messages
pub = rospy.Publisher('turtle1/command_velocity',Velocity)
rospy.spin()
def gotTwistCB(data): #when Twist msg is received
#take values from data and do your job, for example:
outdata = Velocity()
outdata.linear = data.linear.x
outdata.angular = data.angular.z
pub.publish(outdata)
SO data.linear.x/y/z
and data.angular.x/y/z
are the ones that you care about
more on subsribing tutorial here. Also, you may want to check out rosmsg or just run
rosmsg -h
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Asked: 2013-08-03 13:43:38 -0500
Seen: 1,592 times
Last updated: Aug 03 '13
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