joint state publisher's zeros parameter

edit

Two ways to get a dictionary (key, value) on the ROS parameter server: loading a correctly formatted yaml file, or in-line in a rosparam for the node (in this case, joint_state_publisher).

zeros:
joint1: {0.5}
joint2: {0.6}

If that is the actual formatting, then that won't work in either case. The whole zeros parameter should be a dictionary, not its individual elements (which you are doing by adding the curly braces ({, }).

In a yaml (note indentation):

zeros:
  joint1: 0.5
  joint2: 0.6

in-line in launch file:

<node type="joint_state_publisher" ..>
  <rosparam>
    zeros:
      joint1: 0.5
      joint2: 0.6
  </rosparam>
</node>

In both cases indentation is required for the parser to create a proper dictionary out of the yaml.