Hi Anton,

Many thanks for your patient explanation--works like a charm now.  I 
have included my working launch file below.  In the meantime, I will 
definitely check out the OpenRAVE option and your SmartArm code!

--patrick

<launch>
	<param name="robot_description" command="$(find xacro)/xacro.py '$(find 
pi_robot)/urdf/pi_robot.urdf.xacro'" />

	<!-- Start the low-level driver manager with parameters -->
     <node ns="ax12_controller" name="ax12_manager" 
pkg="ax12_controller_core" type="controller_manager.py" required="true" 
output="screen">
         <param name="port_name" type="str" value="/dev/ttyUSB0"/>
         <param name="baud_rate" type="int" value="1000000"/>
         <param name="min_motor_id" type="int" value="1"/>
         <param name="max_motor_id" type="int" value="14"/>
         <param name="update_rate" type="int" value="10"/>
     </node>

     <!-- Load joint controller configuration from YAML file to 
parameter server -->
     <rosparam ns="ax12_controller" file="$(find 
pi_robot)/params/pi_robot_ax12.yaml" command="load"/>

     <!-- Start all Pi Robot joint controllers -->
     <node ns="ax12_controller" name="ax12_controller_spawner" 
pkg="ax12_controller_core" type="controller_spawner.py"
           args="--port /dev/ttyUSB0
		head_pan_controller
		head_tilt_controller
		right_shoulder_pan_controller
		right_shoulder_lift_controller
		right_arm_roll_controller
		right_elbow_controller
		right_wrist_controller
		left_shoulder_pan_controller
		left_shoulder_lift_controller
		left_arm_roll_controller
		left_elbow_controller
		left_wrist_controller
		torso_controller"
         output="screen" />

	<!-- Start the AX12 Joint States Publisher -->
	<node name="ax12_joint_states_publisher" pkg="pi_robot" 
type="ax12_joint_states.py" />
	
	<node name="robot_state_publisher" pkg="robot_state_publisher" 
type="state_publisher">
     	<param name="publish_frequency" value="20.0"/>
     </node>
</launch>