This chapter presents a systematic approachSystematic approach to designing outer-loop controllersOuter-loop controller for mass–stiffness–damping systemsMass–stiffness–damping system (MKC systemsMKC system) that have been pre-compensated through model-based feedback linearization. While inner-loop compensatorsInner-loop compensator transform nonlinear systems into decoupled linear forms, outer-loop controllersOuter-loop controller are tasked with achieving high-level objectives such as accurate reference tracking, disturbance rejectionDisturbance rejection, and robust performance under uncertainties. BuildingBuilding on this structure, we introduce model-based state-feedback controllers, including both standard PD/PID methods and advanced integral-compensated designs. A key focus is placed on addressing the limitations of conventional PID control—namely, its constrained ability to shape transient behaviorTransient behavior due to fixed zero placement. To overcome this, we introduce a two-degrees-of-freedom (2-DOF) control scheme that incorporates integral compensation while allowing independent assignment of both poles and zeros. This enhanced flexibility ensures minimal steady-state error without sacrificing transient performanceTransient performance. Simulation and experimental case studies—spanning payload variations and external disturbances—demonstrate the superiority of the introduced 2-DOF controllers over traditional designs. Specifically, the ability to tailor the eigenstructureEigenstructure of the system enables more precise control responses, even in the presence of unmodeled dynamics. As a result, this chapter lays the foundation for robust, high-performance outer-loop designs that integrate seamlessly withPre-compensated system pre-compensated systemsCompensated system in robotics and other advanced engineering applications.