A Trial Robotic Wheel Unit for Mobile Platform

The rolling wheel is a general, simple but important component for mobile platform that makes the unlimited motion possible. The structure with servo motor, gear-box and encoder is a typical combination for wheel driving mechanism. However, it is difficult to get a compact aspect due to the coaxial installation. As a substitute, the low cost hub motor is also widely used but with some inherent disadvantages. In this paper, we first analyze the layout of general mobile platform chassis and characteristics of ordinary motor-gear-box drive and hub motor drive. Then, we introduce a compact driving wheel mechanism including hub motor, gear-box, and encoder, etc., also give a discussion on its working principle and advantages based on the development of a trial unit.