Vehicle suspension control device and vehicle suspension control method

A vehicle suspension control device, comprising:

• an actuator configured to apply a control force in a vertical direction between an unsprung structure and a sprung structure of a vehicle;
• and
• an electronic control unit configured to control the actuator so as to generate the control force according to a required control amount for reducing vibration of the sprung structure, wherein
• the required control amount includes at least two control terms of a displacement term, a velocity term, and an acceleration term related to displacement, velocity, and acceleration of the sprung structure,
• the electronic control unit is configured to execute:
• a calculation process of calculating a magnitude of a frequency component of each of a plurality of frequency bands included in road surface vibration information related to road surface input to the vehicle or the vibration of the sprung structure due to the road surface input, and
• a gain determination process of determining a control gain of each of the at least two control terms so as to change based on the magnitude of the frequency component of each of the plurality of frequency bands.