Using rqt_plot functionality with dictionary element in parameter

edit

I've been trying to use rqt_plot functionality that involves dictionary but couldn't get it displayed. Obviously, something is not correct somewhere.

rostopic echo /gazebo/model_states

gives me something like below:

name: ['ground_plane', 'asphalt_plane', 'first_2015_trash_can']
pose: 
- 
position: 
  x: 0.0
  y: 0.0
  z: 0.0
orientation: 
  x: 0.0
  y: 0.0
  z: 0.0
  w: 1.0
- 
position: 
  x: 0.775434
  y: 2.97518
  z: 0.0
orientation: 
  x: 0.0
  y: 0.0
  z: 0.0
  w: 1.0
  - 
position: 
  x: 3.82387818665
  y: 3.40090985756
  z: 0.0500026991437
orientation: 
  x: 5.04793066057e-05
  y: -1.94916170948e-05
  z: -0.00420963773061
  w: 0.999991137972

What I'm interested in is the x-position of first_2015_trash_can i.e. one of the pose information of the third object. I've tried to do

rqt_plot /gazebo/model_states/name:'first_2015_trash_can'/pose/position/x

but didn't succeed. I've also tried:

rqt_plot  /gazebo/model_states/name[2]:pose/position/x

but doesn't work either.

Any ideas what could go wrong?