Systems and methods to adjust the operation of various vehicle control systems to improve performance based on detection of a condition in which the vehicle is in an unloaded or reduced normal force state. In one embodiment, the system includes a vehicle control system, a sensor module, and a controller. The controller is configured to receive sensor values from the sensor module. The controller is further configured to determine vehicle motion characteristics based on the sensor values. The controller is further configured to determine that an unloaded state exists when the values of the vehicle motion characteristics exceed threshold values. The controller is further configured to activate countermeasures when the controller determines that the unloaded state exists.

A straddled vehicle includes a front wheel, a rear wheel, an engine which generates a driving force and rotates the rear wheel with the driving force, a front wheel brake and a rear wheel brake which lowers the rotation speed of at least the rear wheel, a first detector which acquires and outputs a pitch rate, a second detector which detects and outputs information concerning rotation of the front wheel, and an ECU including a front wheel lift determination circuit which monitors respective outputs from the first detector and the second detector to determine whether a front wheel lift exists based on at least one of the pitch rate and information concerning rotation of the front wheel. When the front wheel lift exists, the ECU controls the driving source or the braking device so that the driving force is lowered or the rotation speed of the rear wheel is lowered.

A vehicle brake control device generates rear wheel braking torque by an electric motor by pressing a friction member against a rotating member rotating together with the rear wheel, reduces rear wheel braking torque by controlling the electric motor based on a target energization amount calculated from a slip state quantity of the rear wheel, and rapidly stops electric motor rotation motion based on an adjusted target energization amount calculated from the target energization amount and a slip state quantity of a front wheel.

A method and a device for estimating coefficients of friction of a wheel of a vehicle with respect to an underlying surface including decomposing a supplied trajectory into individual curve segments, estimating a lateral force and a slip angle for a front axle of the vehicle, assigning respectively estimated lateral forces and slip angles relating to the associated individual curve segments and storing these value pairs in a memory, estimating a tire characteristic curve for each of the curve segments based on the value pairs stored for the respective curve segment in the memory, estimating a coefficient of friction for each curve segment based on the respectively estimated tire characteristic curve, and storing the estimated coefficients of friction relating to the respectively associated curve segments in a coefficient of friction map.

A tire-based system and method for estimating road surface friction includes a model-based longitudinal stiffness estimation generator using tire-based parameter inputs and vehicle-based parameter inputs; an actual longitudinal stiffness estimation generator using real-time vehicle-based parameter inputs; and a tire road friction estimation generator for deriving a tire road friction estimation from a comparative analysis between the actual longitudinal stiffness estimation and the model-based longitudinal stiffness estimation. A road surface classifier algorithm is employed to generate a road surface type analysis from the road friction estimation, an ambient air temperature measurement, and an ambient air moisture measurement.

A tire state estimation system is provided for estimating normal force, lateral force and longitudinal forces based on CAN-bus accessible sensor inputs; the normal force estimator generating the normal force estimation from a summation of longitudinal load transfer, lateral load transfer and static normal force using as inputs lateral acceleration, longitudinal acceleration and roll angle derived from the input sensor data; the lateral force estimator estimating lateral force using as inputs measured lateral acceleration, longitudinal acceleration and yaw rate; and the longitudinal force estimator estimating the longitudinal force using as inputs wheel angular speed and drive/brake torque derived from the input sensor data.

An apparatus for controlling a vehicle having a motor is provided and includes a driving information sensor that senses driving information of the vehicle including an open value of an APS, an open value of a BPS, a driving wheel speed, a non-driving wheel speed, external temperature, battery temperature, a vehicle speed, and a shift stage. A driving motor generates a driving force and is operated as a power generator when the vehicle coasts to generate electric energy. An ABS that adjusts a braking force applied to a driving wheel. A controller changes a coast regeneration torque subject to regenerative braking by the driving motor when the vehicle is coasting, based on a difference between a driving wheel speed and a non-driving wheel speed, correction temperature determined based on the external temperature and the battery temperature, a friction coefficient of a road, and an operation condition of the ABS.

A method of traction control for a vehicle. Lateral and longitudinal accelerations are measured for a vehicle. A maximum supportable drive torque for a first wheel of the vehicle is calculated as a function of the lateral and longitudinal accelerations. A commanded vectoring brake torque is applied to the first wheel using a brake device. The commanded vectoring brake torque is an amount by which a driveline torque delivered to the first wheel exceeds the maximum supportable drive torque.

A system and method for objectively evaluating an airport runway condition, where conditions pertaining to aircraft landing factors are compiled and used to determine a runway braking condition. One set of conditions pertains to aircraft landing factors, including brake metered pressure, wheel speed, and aircraft deceleration, and a second set of factors relate to pilot controlled parameters. A condition report is generated and made available to pilots of subsequently landing aircrafts prior to landing.

At a time of causing a parking mechanism to execute parking process to switch a parking gear to a locked state when a predetermined parking condition is established and a detected road surface gradient is equal to or greater than a predetermined value, it is determined whether a foot brake has been operated, operation of an automatic braking system is controlled to make a travel speed of the vehicle greater than zero but equal to or less than a set speed if it is determined that the foot brake has not been operated, and the parking process is then executed.