I have 2 Husky robots in Gazebo world moving around. I need to get their battery status like how much battery are they consuming in different tasks? I am using ROS-Indigo with Gazebo-2.2.2 on Ubuntu 14.04.

I tried with PR2 robot as well from link text , but I am not able to understand how to use these. Also, I got PR2 dashboard running but it show "Battery : stale".