Omnidirectional Mobile Robot - Design and Implementation

Abstract

Omnidirectional vehicles have great advantages over conventional (non-holonomic) platforms, with car-like Ackerman steering or differential drive system, for moving in tight areas. They can crab sideways, turn on the spot, and follow complex trajectories. These robots are capable of easily performing tasks in environments with static and dynamic obstacles and narrow aisles. Such environments are commonly found in factory workshop offices, warehouses, hospitals, etc. Flexible material handling and movement, with real-time control, has become an integral part of modern manufacturing. The development of an omnidirectional vehicle was pursued to further prove the effectiveness of this type of architecture and to add a ground vehicle platform that is capable of exceptional maneuverability. Omni-directional vehicles are divided into two categories that describe the type of wheel arrangement they use for mobility: conventional wheel designs and special wheel designs. This chapter introduced an omnidirectional mobile robot with Mecanum wheels for educational purposes. The robot has full omnidirectional motion capabilities, thanks to its special Mecanum wheels. Some information about conventional and special wheels designs, mechanical design aspects of the Mecanum wheel and also of the robot, kinematic models, as well as electronics and control strategies have been presented. Thanks to its motion capabilities and to its different control possibilities, the robot discussed in this chapter could be used as an interesting educational platform. At this time, three solutions for motion control have been implemented in the microcontroller: ? Remote control mode; ? Line-follower mode; ? Autonomous mode, thanks to an ultrasonic pair sensors and bumper bars. To know the position of the robot according to a reference point, a video camera was used for ground image capture.