Choosing a drive system

Hi all,<BR>We are designing a robot which will weigh approx. 60kg. Please suggest me a pair of dc gearhead motors (with optical encoder mounting shaft available), which can be used with AX3500 in mixed speed/steerig command.

Thanks! <BR>

These NPC Robotics <a target="_blank" href="www.npcrobotics.com/products/viewprod.as...;cat=20&mode=gfx">motors should be just what you are looking for. They have a threaded shaft in the end for an encoder.