We present the recent development work on the electrical and hardware design of our modular and scalable mobile robot platform for education and research. The goal of the project is to develop a low-cost and extensible modular mobile robot platform for education and research activities. We present a differential drive robot with distributed input/output modules. The project is scalable to be easily extended to make complex autonomous robot systems including four wheel drive and omnidirectional robots. The software design is based on ROS framework that is based on open source software.