use ros_arduino_bridge with other hardwares
hi everyone I want to use ros_arduino_bridge stack by Patrick Goebel for my mobile robot base controller. There are two hardwares that patrick has used in it. Pololu VNH5019 dual motor controller shield ( http://www.pololu.com/catalog/product... ) or Pololu MC33926 dual motor shield ( http://www.pololu.com/catalog/product... ) for drive the motors and Robogaia Mega Encoder shield ( http://www.robogaia.com/two-axis-enco... ) for encoders.
Unfortunately the encoder shield is out of stock and both two shields are so expensive from my country because i need to import them.
Is it possible to use other shields for this stack??? I am a new learner in robotics and ROS and some more practical advice can help me because now i am so confused about how to do for my work without these two hardwares :((((((