This paper describes the kinematical analysis and control of a large spatial robot for base motion compensation using an inertial measurement unit. The proposed method is intended for a 6 degrees of freedom serial manipulator, which compensates a large-amplitude spatial motion at its base such that the end effector maintains to a high degree a prescribed target location. Hereby, the robot circumvents hand wrist singularities by a new virtual redundant joint approach. The overall system is tested for a KUKA KR500 system and computergenerated as well as real wave signals with large amplitudes. © 2012 IEEE.