Abstract: An estimated brake rotor temperature is provided including a cooling effect during active braking as well as when braking is inactive. The cooling effect is based on a difference between the rotor temperature and sensed ambient temperature and is also preferably based on wheel speed. In an active braking mode, a heating effect is provided based at least on sensed wheel speed. If no brake pressure signal is available, the heating effect is further based on vehicle deceleration. The heating effects for front and rear brake units are relatively compensated for differences in heat generation due to load shifts during braking, the compensation being preferably based on vehicle deceleration. The brake rotor temperature estimation is realized in a programmed digital computer but does not use computer resource hungry exponential functions.

Abstract: A traction control for a motor vehicle responds to detection of a rough road surface so as to shift control away from propulsion power reduction and toward brake control to an over-spinning driven wheel when the rough road surface is detected. This better adapts the traction control to a road surface that may have a high coefficient of friction but produces intermittent loss of traction due to wheel hop or normal force fluctuations due to the rough road surface. The lower power reduction is obtained by increasing a target brake pressure used to derive a brake pressure error signal from which from which a power reduction command is derived. A delta target brake pressure may also be increased to provide a higher target velocity for the driven wheel propulsion.

Abstract: An estimated brake rotor temperature is provided including a cooling effect during active braking as well as when braking is inactive. The cooling effect is based on a difference between the rotor temperature and sensed ambient temperature and is also preferably based on wheel speed. In an active braking mode, a heating effect is provided based at least on sensed wheel speed. If no brake pressure signal is available, the heating effect is further based on vehicle deceleration. The heating effects for front and rear brake units are relatively compensated for differences in heat generation due to load shifts during braking, the compensation being preferably based on vehicle deceleration. The brake rotor temperature estimation is realized in a programmed digital computer but does not use computer resource hungry exponential functions.

Abstract: A traction control for a motor vehicle responds to detection of a rough road surface so as to shift control away from propulsion power reduction and toward brake control to an over-spinning driven wheel when the rough road surface is detected. This better adapts the traction control to a road surface that may have a high coefficient of friction but produces intermittent loss of traction due to wheel hop or normal force fluctuations due to the rough road surface. The lower power reduction is obtained by increasing a target brake pressure used to derive a brake pressure error signal from which from which a power reduction command is derived. A delta target brake pressure may also be increased to provide a higher target velocity for the driven wheel propulsion.

Abstract: A vehicle powertrain torque control provides an engine drag control mode of operation during periods of undesired engine drag induced wheel slip by modifying the torque of the vehicle engine in closed loop control to maintain a driven wheel speed at a predetermined target velocity lower than the vehicle speed by a target velocity difference providing as much engine braking as is consistent with a desired degree of lateral traction. The control derives a velocity error as the difference between the driven wheel speed and the target velocity and derives and delivers to the powertrain a torque command for reducing the velocity error. The torque control determines the engine drag control mode in response to the wheel speed sensors, preferably causing entry of the engine drag control mode when the driven wheel speed that is closest to the vehicle speed falls below the target velocity while powertrain delivered torque and throttle position are below predetermined values indicative of deceleration.

Abstract: A vehicle brake control providing understeer correction through an increase in differential brake pressure favoring the inside wheel applies the increase, in the absence of anti-lock braking activity, across the rear wheels unless one or more sensors indicates a likely low traction condition on the inside rear wheel, in which case the increase is applied to the front pair of wheels. Preferred sensors include a suspension position sensor for the inside rear wheel or other sensor derived information from a suspension control system that indicates large body roll in a turn together with forward body pitch. In the absence of a suspension control system, preferred sensors include vehicle lateral and longitudinal accelerometers indicating vehicle roll and pitch together with a steer angle sensor indicating a significant turn. An indication could also be derived from a normal force sensor on the wheel or normal force information derived from other sensors such as a tire pressure sensor.

Abstract: An improved engine torque control method uses existing powertrain sensors and controls to reliably detect and suppress power-hop with minimum degradation of vehicle acceleration. Power-hop is detected by identifying a characteristic wheel jerk magnitude and oscillation frequency based on driven wheel speeds. Once a power-hop condition is detected, the control method computes a desired engine torque output for suppressing the detected power-hop without unnecessarily degrading vehicle performance, based on the wheel jerk magnitude, the engine speed and vehicle acceleration. A combination of engine cylinder fuel cut-off and spark retard is then scheduled for reducing the engine output torque to the desired level for the duration of the power-hop condition.

Abstract: A vehicle traction control increases the allowed wheel spin for a driven wheel when (1) sensed vehicle speed is within a predetermined speed range corresponding to near maximum engine speed for the sensed currently used gear of the transmission, (2) sensed vehicle turn curvature is within a predetermined curvature range of zero curvature, (3) sensed vehicle longitudinal acceleration has not been below a predetermined high acceleration for a predetermined time, and (4) sensed vehicle engine speed has not been below a predetermined high engine speed for the predetermined time. The tests are calibrated to provide the increase in a very narrow range of conditions corresponding to high performance operation, and particularly power shifts of a manual shift transmission, on a racetrack with a high coefficient surface.