For experimentation's sake I am writing a node for a turtlebot that publishes data as if it were '/camera/depth/registered_points', a PointCloud2 message. I can not get rviz to show this data. I think I'm missing a basic understanding of frames. The rviz error is :> "Transform> [sender=/turtlebot_talktest_19193_1389894558845]> For frame [/map]: Fixed Frame> [caster_front_link] does not exist"
Here is some of the code that creates the point cloud. I'm hoping in the end for some colored dots on the rviz screen. For brevity I have not included my 'import' section.
def make_cloud() :
rospy.init_node('turtlebot_talktest', anonymous=True)
#
pub_cloud = rospy.Publisher("camera/depth_registered/points", PointCloud2)
pcloud = PointCloud2()
c_height = 6
c_width = 6
# make point cloud
fields = [PointField('x',0, PointField.INT16, 1)]
cloud2 = [1,2,6,1,2,6,
1,2,6,1,2,6,
1,2,6,1,2,6,
1,2,6,1,2,6,
1,2,6,1,2,6,
1,2,6,1,2,6]
cloud_struct = struct.Struct(pc2._get_struct_fmt(False, fields))
buff = ctypes.create_string_buffer(cloud_struct.size * len(cloud2))
point_step, pack_into = cloud_struct.size, cloud_struct.pack_into
offset = 0
for p in cloud2:
pack_into(buff, offset, p)
offset += point_step
pcloud.header = Header()
pcloud.header.stamp = rospy.Time.now()
pcloud.header.frame_id = '/map'
pcloud2 = PointCloud2(header=pcloud.header,
height=c_height,
width=c_width,
is_dense=False,
is_bigendian=False,
fields=fields,
point_step=cloud_struct.size,
row_step= len(cloud2) / c_height,
data=buff.raw)
pub_cloud.publish(pcloud2)
return
I thought by changing the 'frame_id' to '/map' I was on the right track. Is there a simple change that I can make so that rviz will display these points?
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