What are the types of car driving methods? Which one is better?
The way of driving wheels in automobiles: Generally, they are distinguished according to the number and position of driving wheels. The most basic is that they can be divided into two categories: two-wheel drive and four-wheel drive. According to the position of the engine in the vehicle and the position of the driving wheels in the two-wheel drive, it can be further subdivided into: front and rear drive (FR), front and front drive (FF), rear and rear drive (RR), and center rear Drive (MR) and other forms. The four-wheel drive is divided into: four-wheel drive, full-time four-wheel drive, timely four-wheel drive, and timely hybrid drive. The advantages and disadvantages of the front rear drive, front front drive, rear rear drive, and center rear drive in two-wheel drive Front and rear drive (FR): The front wheels are responsible for steering, and the rear wheels are responsible for driving the entire vehicle. Advantages: When the vehicle is driving, accelerating or climbing on a good road surface, the adhesion of the driving wheels is large, and the traction, steering stability and driving smoothness are superior to the front-drive vehicle, and the tire has a long service life. Because the engine, clutch, and gearbox of the front and rear drive vehicles have a better layout space by the cab, it is conducive to vehicle maintenance and repair. < Front Front Drive (FF): Disadvantages: The front wheel is the driving wheel, which is also the direction of the wheel, and the load of the front wheel is large. Therefore, the tire life of the steering wheel is short. Because the engine, transmission and steering mechanism are all arranged at the front end, the layout space is small, the manufacturing process is complicated, if the frontal collision is large, the maintenance cost is high, and the maintenance is difficult. When the vehicle starts, accelerates or climbs on a good road, the traction decreases. Advantages: Due to the heavy load on the front axle, the vehicle has good handling stability during high-speed driving and directional stability during braking. When driving on snow or slippery roads, it is also helpful to ensure a stable direction. Due to the front-wheel drive, the space of the cab and the trunk is increased, and the riding comfort and cargo loadability are improved. The engine leans away from the drive wheels, making power transmission efficiency high and improving fuel economy. Rear Rear Drive (RR) Advantages: This rear-rear drive layout is very flexible, with good starting and climbing performance, light and flexible steering, no protrusions on the cab floor, good fuel economy, and improved rationality of braking force distribution. Disadvantages: Limited space in the trunk and noise and vibration in the rear row cannot be eliminated. Easily affected by crosswinds. Vehicle heat dissipation is not as good as front and rear drive. The safety of fuel tank layout is relatively difficult. The characteristics of the steering transition are obvious when the vehicle is turning. Straight-line driving performance is normal and there is a danger of overturning when braking suddenly when rolling backwards on a steep slope. Rear Rear Drive (MR) Advantages: The biggest advantage is that the central engine and traditional mechanisms are concentrated in the middle of the car. When the vehicle turns, as soon as the steering wheel turns, the car will quickly follow the steering. The time difference between the two is very short, and the body follows the steering. The characteristics of the action are particularly good. Disadvantages: Due to its driving method, the seating space of the cab is determined, and the space for passengers is small. Generally, the rear seats are two seats. Also, the rear seats are noisy. It is generally a high-end vehicle that pursues sports performance, and uses a rear-mounted layout. Such as Ferrari and Lamborghini. The advantages and disadvantages of time-sharing four-wheel drive, full-time four-wheel drive, timely four-wheel drive, and hybrid drive in the four-wheel drive. Time-sharing four-wheel drive: Time-sharing four-wheel drive is generally used in off-road vehicles. Two-wheel and four-wheel drive modes are realized by turning on or off the transfer box. The fuel economy of the two-wheel drive mode is better when driving normally. If it is a four-wheel drive mode, not only is it fuel-efficient, but the vehicle's maneuverability, smooth balance, and stability and safety are not as good as those of the two-wheel drive mode. Especially when turning at high speeds, the phenomenon of understeer is manifested ~ dangerous. Therefore, it is necessary to be very cautious when using the four-wheel mode when driving normally on a good road. Generally, the four-wheel drive system should be turned off. The time-sharing four-wheel drive system is only used for the relief of poor roads at low speeds, such as sand and gravel, muddy bumps, rain, snow and ice. Therefore, it has a strong ability to escape. Since the time-sharing four-wheel-drive vehicles mostly use non-load-bearing bodies, the riding comfort is poor. Full-time four-wheel drive: The full-time four-wheel drive can realize the driving of the suitable four-wheel drive on hard roads. It is suitable for various road conditions, especially on wet roads and winter roads. It has good driving capacity and low gear. The acceleration is good, the driving force is not affected by the change in the distribution of the bamboo lotus of the car, the driving stability on muddy and snow is good, the sensitivity to crosswind is small, and the wear of each tire is relatively uniform. Mainly manifested in good handling, stability and balance, good grip on the four wheels, and there will be no understeer or oversteer. Disadvantages: complex structure, large car quality, high manufacturing costs, and increased fuel consumption in urban areas by about 5% -10%. Timely four-wheel drive: The disadvantage of timely four-wheel drive is that it is not suitable for driving on harsh roads and has a moderate ability to get out of trouble. Advantages: When the vehicle is traveling straight, the front and rear axles have the same speed, and there is no active mechanical speed difference. The vehicle is basically in the front-drive or rear-drive state, and the fuel economy is good. When turning, there is a speed difference between the front and rear axles. When the speed difference does not exceed the limit, the vehicle's steering will not be affected. When it is exceeded (the wheels are slipping), the electronic control system will control the hydraulic mechanism to compress the clutch to achieve four-wheel drive. In other words, the time-sharing four-wheel drive is usually two-wheel drive. If there is wheel slip, it will automatically adjust to the four-wheel drive system to improve the safety of the vehicle. Hybrid drive: There are two ways to drive a hybrid drive. The most prominent advantages are lower fuel consumption (energy saving) and lower pollution to the environment. It reduces emissions, reduces noise, and improves passenger comfort. Which drive form is good: Generally speaking, in terms of applicability, safety, and controllability, the full-time four-wheel drive is better. Among the two drives, the front and rear drives are better. At present, most of the market is front-mounted front-drive vehicles, which have good power transmission (less power loss and high transmission efficiency) and good fuel economy, and have a large riding space and trunk, which is more affordable.