In-Wheel Motor (IWM) vehicle design introduces a lot of benefits for manufacturers. However, it also decreases the ride comfort in the mid-range of perceivable frequencies. The Unsprung Negative Skyhook (UNS) damper control method offers ride comfort improvement in the same frequency range but has its limitations. This thesis proposes two control methods with the aim of maintaining the benefits of the UNS while eliminating the drawbacks. One method is based on a Frequency-range selector (FRS) used in semi-active control. This method allows for a simple but crude frequency estimation by using single sensor information. The second method uses a Short-Time Fourier Transform (STFT) frequency estimator to determine the instantaneous frequency of the vibration. Depending on the vibration frequency, the controllers switch between Skyhook and UNS control to improve overall behaviour. The proposed control methods, as well as state-of-the-art control methods, are evaluated using quarter car and full vehicle simulations. For full vehicle simulations, the models are implemented in IPG CarMaker for realistic dynamic behaviour. Road profiles are obtained from the Gerotek Testing Facility for realistic inputs. Both proposed control methods show improvements for quarter car simulations. For full vehicle simulations, the FRS control method is not able to replicate these improvements. The STFT control method does achieve improvements for all simulations but is limited by its governing models. Finally, suggestions are proposed to further improve the effectiveness of the mixed control method.