標題: [資訊] Mitsubishi's Super All Wheel Control (S-AWC) [打印本頁] 作者: carwing 時間: 2008-12-16 12:59 PM 標題: Mitsubishi's Super All Wheel Control (S-AWC)
When it comes to traction at the limits, Mitsubishi's Lancer EVO is oneof the best. Gravel, snow, mud, ice, or dry pavement, the EVO shows offits rally heritage, making average drivers look good and good driverslook great. You don't have to be a rally driver to take advantage ofthis type of traction. The EVO works equally well taming the hazards ofeveryday driving, thanks to the car's Super All Wheel Control. Super All Wheel Control (S-AWC) is a combination of four separatesystems integrated by the S-AWC control unit. Previous Lancer Evolutionmodels integrated only three systems, but the new car integrates ABS(Antilock Brake System), ACD (Active Center Differential), AYC (ActiveYaw Control) and ASC (Active Stability Control). Let's look at how itimproves vehicle safety by making handling predictable.To control all the systems, the computer needs toknow two critical pieces of information: what the car is doing and whatthe driver wants. To determine what the car is doing, the EVO usesvehicle speed and yaw rate sensors to measure the movement of the carin all directions. Then the computer looks at driver inputs such assteering wheel angle, throttle or brake application, and driver inputfrom the switch on the steering wheel that allows the driver to selectTarmac, Gravel or Snow mode. By comparing the vehicle yaw informationwith the driver input information, the S-AWC computer controls the carto make it go where you want, using the principle of torque vectoring.Torque vectoring is simply the application oftorque or braking force to move the vehicle in the desired direction.Each of the four S-AWC systems is used to provide the torque vectoringunder different conditions. The Active Centre Differential varies thetorque between the front and rear axles. It works like a limited slipunit so that if one axle looses traction, the power is applied to theother axle to keep the power to the road. The Active Stability Control system uses both brake control and enginecontrol to reduce wheelspin for improved traction and skid control. TheActive Yaw Control can vector torque by shifting the power between theleft and right side tires. By applying more torque to one side, itturns the car away from the side where the torque is applied. While AYC works great during acceleration, it doesn't work as wellduring deceleration. That's where the ABS comes into force. By applyingbrakes selectively, the car maintains directional control duringbraking. Many drivers are aware of the directional control and safetyprovided by ABS and electronic stability control, but few haveexperienced how integrating these systems with Yaw control and anactive centre differential can make a car's handling superb.
Remember the input switch on the steering wheel for mode selection?Well, if you choose Tarmac mode, the system maximizes corneringperformance. This mode is best selected when traction conditions aregood, such as dry pavement. The Gravel mode selection tells the S-AWCcomputer to maximize traction instead of cornering performance.Although called "Gravel" mode, it is also suitable for wet or coldroads where traction is limited. Finally there is the Snow mode. Thismode maximizes vehicle stability for control on slippery surfaces. Thenice part about the EVO systems is that all you have to do is selectthe mode to match the road surface and the computer controls all thesystems to maximize driving fun and safety.Testing by Mitsubishi on a dry track and slipperyice surfaces demonstrated the benefits of the S-AWC system. In bothsituations, the amount of steering wheel movement by the driver tomaintain cornering control was much less than on the same vehiclewithout S-AWC. This indicates the vehicle is easy to control. On a 2.4kilometre paved track, the S-AWC system enabled drivers to get aroundthe track 1.5 seconds faster than cars without S-AWC. One and a halfseconds may not sound like much, but in racing terms that is thedifference between a top runner and the back of the pack. The S-AWCsystem in Mitsubishi's Lancer EVO enables it to run at the front of thepack.
