Thursday, December 27, 2012

Intelligent 4WD System in 2013 Ford Escape


There are many different types of 4 wheel drive systems on vehicles now a days (and many ways to spell and abbreviate 4 wheel drive like 4WD, 4x4, Four-Wheel Drive, four-by-four, AWD, all-wheel drive ) , but the 2013 Ford Escape features one of Ford's most innovative 4WD systems yet. Here is a little about how it works:

• The all-new Ford-engineered 4WD system utilizes software that preemptively reassesses road conditions every 16 milliseconds – about 20 times faster than it takes to blink an eye – and adjusts the power split from front wheels to back to give drivers a precise blend of handling and traction at all times
• The all-new system splits torque produced by the powertrain between the front and rear axles for a key advantage: seamless power transfers that help keep the vehicle on the driver’s intended path, helping to minimize understeer or oversteer conditions
• The system measures actual directional input from wheel sensors, lateral acceleration and yaw rates, and compares it to driver responses via the steering wheel and accelerator, and then prompts the system to react accordingly
• During snowy and wet conditions that cause excess wheelslip, the intelligent “torque on demand” 4WD system on Escape can send up to 100% of available drivetrain power to the front or rear axles, and determines the power distribution by measuring wheel speed differences in correlation with driver steering input and requested powertrain torque
• In constant-speed highway conditions, Escape operates in 2WD mode, providing 100% of the power to the front wheels. The 4WD controller will determine how much torque should be sent to the front and rear axles, but it goes one step further than most stability control systems – it anticipates how much torque will be required by analyzing up to 25 inputs every 16 milliseconds
• At speeds below approximately 20 mph, the system provides high levels of torque to the rear axle with a focus on traction maximization
• At speeds above approximately 20 mph, the system is tuned for balanced torque distribution to improve driving feel, handling, cornering and response
• Available on SE, SEL and Titanium

ENGINEERING INSIGHT: 
Intelligent 4WD System - How It Works

The system measures:
• All four wheel speeds to determine if there is a speed difference between the front and rear wheels
• Actual speed and driver-requested torque to maximize low-speed traction
• Steering wheel angle to determine the driver’s intended direction
• Lateral acceleration to determine the appropriate torque distribution while cornering
• Yaw rate to determine the vehicle’s rotation about its vertical axis

Key Driver Benefits
• Understeer and oversteer can be controlled more quickly
• Torque steer is virtually eliminated
• Activates more intelligently than previous-generation automatic systems
• Improves vehicle dynamics, ride and handling