ROS Programming: Building Powerful Robots

The caster wheel design

You can use any caster wheel that can be move freely on the ground. The main use of caster wheels is distributing the weight of the robot and balancing it. If you can use a spring suspension on the caster wheel, it can help you navigate the robot on uneven terrain.

Here are some caster wheels that you can use for this robot:

http://www.robotshop.com/en/robot-wheel.html.