A controller estimates a state of a vehicle based on a wheel speed sensor provided on the vehicle, and outputs a control signal to a shock absorber provided between a wheel and a vehicle body according to the estimated state of the vehicle. The controller uses information of a sensor of an in-vehicle apparatus other than an apparatus dedicated to the shock absorber as an observed value in the estimation of the state of the vehicle. In other words, the controller uses sensor information of a navigation apparatus corresponding to the in-vehicle apparatus other than the shock absorber, more specifically, gyro information meaning information of a gyro sensor mounted on the navigation apparatus as the observed value in the estimation of the state of the vehicle.

A method for reshaping an electric drive signal of a real-time damper in a sprung mass system includes detecting a periodic frequency and magnitude of a target periodic vibration of a sprung mass. The periodic vibration has velocity and elasticity components that are 90 degrees out-of-phase. An electric drive signal to the real-time damper is reshaped by a controller depending on polarity of the velocity component to thereby generate a composite drive signal. The damper is energized using the composite drive signal to modify a damper force. Reshaping the electric drive signal includes injecting a force and/or an intermittent drive suppression component onto the electric drive signal based on the frequency and magnitude. The sprung mass system may have a frame and body, motion and wheel speed sensors, the real-time dampers, road wheels, and a controller programmed to perform the method.

A method for determining a tyre normal force range (F.sub.z,min, F.sub.z,max) of a tyre force (F.sub.z) acting on a vehicle (100), the method comprising; obtaining (S1) suspension data (310) associated with a suspension system of the vehicle (100); obtaining (S2) inertial measurement unit, IMU, data (320) associated with the vehicle (100); estimating (S3), by a suspension-based estimator (330) a first tyre normal force range (F.sub.z1,min, F.sub.z1,max) based on the suspension data (310); estimating (S4), by an inertial force-based estimator (340), a second tyre normal force range (F.sub.z2,min, F.sub.z2,max)based on the IMU data (320); and determining (S5) the tyre normal force range (F.sub.z,min, F.sub.z,max) based on the first tyre normal force range (F.sub.z1,min, F.sub.z2max) and on the second tyre normal force range (F.sub.z2,min, F.sub.z2,max).

An electrically powered suspension system includes: an electromagnetic actuator configured to generate a driving force related to vibration damping of the vehicle; an information acquisition unit configured to acquire information on a stroke velocity of the electromagnetic actuator; a target damping force calculation unit configured to calculate a target damping force based on the stroke velocity; a drive control unit configured to control driving of the electromagnetic actuator based on the target damping force; and a filter processing unit configured to perform a filtering process by applying a predetermined filtering characteristic to the stroke velocity. The filter processing unit has a plurality of filtering characteristics set in a second frequency region, which has a frequency higher than that of a first frequency region. The filter processing unit selectively applies, among the plurality of filtering characteristics, one filtering characteristic that is based on the stroke velocity to the stroke velocity.

A vibration damping control apparatus of a vehicle executes preview vibration damping control for controlling a control force generating apparatus on the basis of a final target control force including a first target control force computed by using preview information. When the vibration damping control apparatus determines that the probability that a road surface condition has changed after a past point in time is high, the vibration damping control apparatus executes particular control for setting the magnitude of the first target control force to become smaller.

A damping control device is configured to acquire, as a preview condition amount, an unsprung condition amount at a predicted passing position where a wheel of a vehicle is predicted to pass, based on preview reference data being sets of data in which unsprung condition amounts and pieces of positional information of the wheel are linked to each other. The unsprung condition amounts indicate a displacement condition of an unsprung portion displaced in a vertical direction due to a displacement of a road surface acquired when the vehicle has traveled on the road surface. The damping control device is configured to execute, at a timing when the wheel passes through the predicted passing position, preview damping control to cause control force to agree with a target control force.

A method for estimating damping characteristics of shock absorbers in an active or semi-active suspension involves providing a reference model of a nominal relation between a road severity index related to vertical acceleration values, and the mean driving current of the control valves of the shock absorbers, acquiring respective relative acceleration or speed data of at least the front wheels of the vehicle with respect to the vehicle body, determining a value of the road severity index starting from relative acceleration or speed data of the front wheels of the vehicle with respect to the vehicle body, acquiring values representative of the mean driving current of the control valve of each shock absorber, comparing acquired value of the mean driving current with an expected value of the nominal mean driving current determined as a function of the road severity index according to the reference model, and determining a degradation condition if the acquired value does not correspond to the expected value.

An electric vehicle comprises a vehicle chassis extending along a longitudinal axis and a rotatable vehicle drive axle disposed along a transverse axis and having opposed ends that are configured for attachment of a pair of opposed drive wheels. The electric vehicle also comprises a selectively movable electric propulsion motor comprising a rotatable motor shaft rotatable about a motor axis, the electric propulsion motor configured to be mounted within the vehicle chassis and operatively coupled to the rotatable vehicle drive axle and opposed drive wheels, the motor axis configured to be oriented in a substantially vertical direction.

A method for reshaping an electric drive signal of a real-time damper in a sprung mass system includes detecting a periodic frequency and magnitude of a target periodic vibration of a sprung mass. The periodic vibration has velocity and elasticity components that are 90 degrees out-of-phase. An electric drive signal to the real-time damper is reshaped by a controller depending on polarity of the velocity component to thereby generate a composite drive signal. The damper is energized using the composite drive signal to modify a damper force. Reshaping the electric drive signal includes injecting a force and/or an intermittent drive suppression component onto the electric drive signal based on the frequency and magnitude. The sprung mass system may have a frame and body, motion and wheel speed sensors, the real-time dampers, road wheels, and a controller programmed to perform the method.

An electrically powered suspension system includes: an electromagnetic actuator configured to generate a driving force related to vibration damping of the vehicle; an information acquisition unit configured to acquire information on a stroke velocity of the electromagnetic actuator; a target damping force calculation unit configured to calculate a target damping force based on the stroke velocity; a drive control unit configured to control driving of the electromagnetic actuator based on the target damping force; and a filter processing unit configured to perform a filtering process by applying a predetermined filtering characteristic to the stroke velocity. The filter processing unit has a plurality of filtering characteristics set in a second frequency region, which has a frequency higher than that of a first frequency region. The filter processing unit selectively applies, among the plurality of filtering characteristics, one filtering characteristic that is based on the stroke velocity to the stroke velocity.