Vehicle Dynamics Synthetic Control Description

Vehicle Dynamics Synthetic Control Description

Oversteer restraint by traction force distribution control
When the vehicle rear has a tendency of outside skid during cornering, the BCM judges it as an oversteer (a tendency of rear wheels' sliding out) and carries out restraining control in cooperation with the 4WD control module. The BCM calculates the optimum distribution rate of traction force for the front and rear wheels based on the degree of oversteer, and transmits the required distribution rate of traction force (a reduction in wheels' traction force) to the 4WD control via CAN communication. Receiving this information, the 4WD control module reduces traction force in the rear wheels and increases it in the front wheels and then restrains the oversteer. However, when the vehicle changes the state of driving motion from Vehicle Dynamics Synthetic Control area to ESP control area, stability control on ESP control module is given priority.

Understeer restraint by traction force distribution control
When the vehicle front has a tendency of outside skid during cornering, the BCM judges it as an understeer (a tendency of front wheels' sliding out) and carries out restraining control in cooperation with the 4WD control module. The BCM calculates the optimum distribution rate of traction force for the front and rear wheels based on the degree of understeer, and transmits the required distribution rate of traction force (an increase in rear wheels' traction force) to the 4WD control via CAN communication. Receiving this information, the 4WD control module increases traction force in the rear wheels and reduces it in the front wheels and then restrains the understeer. However, when the vehicle changes the state of driving motion from Vehicle Dynamics Synthetic Control area to ESP control area, stability control on ESP control module is given priority.

Vehicle control while ABS / ESP are working
When ABS is working, BCM transmits an order based on information from ESP control module to 4WD control module via CAN communication to minimize the rear wheels' traction force and then ABS effect works well. On the other hand, when ESP is working, BCM transmits another order to 4WD control module to reduce the rear wheels' traction force and then ESP functions as well.