The UMASS uBot-4 is a two wheeled, dynamically stable, bimanual mobile manipulator. It is a compact, safe, and cost effective platform with many features such as whole body postural control, force sensing actuators, two 4-DOF arms, and a small footprint. It is the latest in a series of small mobile robots that originated with the uBot-0.5 (ca. 1997). This paper presents the motivations for the ...