Design and Analysis of a Hybrid Mobile Robot Mechanism With Compounded Locomotion and Manipulation Capability

This paper presents a novel design paradigm as well as the related detailed mechanical design embodiment of a mechanically hybrid mobile robot. The robot is composed of a combination of parallel and serially connected links resulting in a hybrid mechanism that consists of a mobile robot platform for locomotion and a manipulator arm for manipulation. Unlike most other mobile robot designs that have a separate manipulator arm module attached on top of the mobile platform, this design has the ability to simultaneously and interchangeably provide locomotion and manipulation capability. This robot enhanced functionality is complemented by an interchangeable track tension and suspension mechanism that is embedded in some of the mobile robot links to form the locomotion subsystem of the robot. The mechanical design was analyzed with a virtual prototype that was developed with MSC ADAMS software. The simulation was used to study the robot’s enhanced mobility characteristics through animations of different possible tasks that require various locomotion and manipulation capabilities. The design was optimized by defining suitable and optimal operating parameters including weight optimization and proper component selection. Moreover, the simulation enabled us to define motor torque requirements and maximize end-effector payload capacity for different robot configurations. Visualization of the mobile robot on different types of virtual terrains such as flat roads, obstacles, stairs, ditches, and ramps has helped in determining the mobile robot’s performance, and final generation of specifications for manufacturing a full scale prototype.