Abstract:
Apparatus (or method) for estimating a gripping characteristic of a vehicle wheel of a vehicle on a ground contact surface includes first input section (or step), a second input section (or step) and an output section (or step). The first input section sets a first input which is a ratio of a first wheel force acting on the vehicle wheel in the ground contact surface in a first direction, and a first wheel slip degree. The second input section sets a second input which is a ratio of a second wheel force acting on the vehicle wheel in the ground contact surface in a second direction, and a second wheel slip degree of the vehicle wheel. The output section determines, from the first and second inputs, an output which is a grip characteristic parameter indicative of the gripping characteristic of the vehicle wheel.
Abstract:
A vehicle steering apparatus includes a vehicle steering system and a supplemental steering force applying device. The supplemental steering force applying device is configured and arranged to apply a supplemental steering force to the vehicle steering system to reduce a steering load on the operator. The supplemental steering force applying device includes a steering torque detecting section, a rectilinear driving condition detecting section, a pulling suppression control section. The rectilinear driving condition detecting section is configured and arranged to detect a rectilinear driving condition of the vehicle. The pulling suppression control section is configured and arranged to adjust the supplemental steering force in a direction canceling a pulling force imparted on the vehicle during the rectilinear driving condition by using a pulling suppression force calculated based on historical data of the steering torque detected during the rectilinear driving condition.