Patent ID: 8510021

Claim:
A vehicle control system in a vehicle including driving power transmission members which are engaged with each other with a slack on a driving power transmission path through which a driving power is transmitted from a driving power source to a drive wheel, the vehicle control system comprising: an acceleration and deceleration determiner configured to determine whether or not a driver has performed a predetermined acceleration or deceleration operation; a driving power transmission state detector configured to detect a value of at least one of a relative rotational position and a relative rotational speed of an input shaft and an output shaft provided on the driving power transmission path, the input shaft being positioned upstream of an engagement portion of the driving power transmission members which are engaged with each other with a slack on the driving power transmission path, and the output shaft being positioned downstream of the engagement portion on the driving power transmission path; an acceleration and deceleration controller configured to execute acceleration or deceleration control for accelerating or decelerating the input shaft or the output shaft to reduce at least one of a contact speed and a transmission torque of the driving power transmission members based on the value detected by the driving power transmission state detector, if the acceleration and deceleration determiner determines that the driver has performed the acceleration or deceleration operation, wherein the acceleration and deceleration determiner is configured to determine that a transient operation in which a change amount in an operation performed by the driver to transition the driving power source from a decelerated state to an accelerated state or from the accelerated state to the decelerated state is larger than a predetermined value is the predetermined acceleration or deceleration operation; and the vehicle control system further comprising: a throttle valve opening degree sensor configured to detect an opening degree of a throttle valve for controlling an amount of air supplied to an engine which is the driving power source; wherein the acceleration and deceleration determiner is configured to determine that the driver has performed the transient operation for transitioning the driving power source from the decelerated state to the accelerated state if a difference of the throttle valve opening degree detected by the throttle valve opening degree sensor is larger than a difference threshold which is a predetermined positive value and the throttle valve opening degree is larger than a predetermined opening degree threshold.