PTUPosture crashes with multiple PTUs

[pronobis]

When multiple PTUs are created with the same parent, MORSE crashes with the following traceback

Traceback (most recent call last):
  File "/opt/sara_morse/lib/python3.3/site-packages/morse/blender/calling.py", line 54, in sensor_action
    component_action(contr)
  File "/opt/sara_morse/lib/python3.3/site-packages/morse/blender/calling.py", line 50, in component_action
    cmpt_object.action()
  File "/opt/sara_morse/lib/python3.3/site-packages/morse/core/sensor.py", line 76, in action
    self.default_action()
  File "/opt/sara_morse/lib/python3.3/site-packages/morse/sensors/ptu_posture.py", line 72, in default_action
    if not self._ptu_obj:
AttributeError: 'PTUPosture' object has no attribute '_ptu_obj'

Example:

        self.prosilica_tilt = PTU("prosilica_tilt") 
        self.append(self.prosilica_tilt)

        self.xtion_tilt = PTU("xtion_tilt")
        self.append(self.xtion_tilt)

        self.prosilica_tilt_state = PTUPosture("prosilica_tilt_state")
        self.prosilica_tilt.append(self.prosilica_tilt_state)

        self.xtion_tilt_state = PTUPosture("xtion_tilt_state")
        self.xtion_tilt.append(self.xtion_tilt_state)

The reason seems to be that the c.name in:

   def _get_ptu(self, obj):
        if "PanBase" in [c.name for c in obj.children]:
            return obj
        elif not obj.parent:
            return None
        else:
            return self._get_ptu(obj.parent)

is not PanBase anymore but rather PanBase.001

[pronobis]

A small fix that works for me is in pull request #537.