【導(dǎo)讀】控制系統(tǒng)穩(wěn)定性是針對提高駕駛安全性提出的一系列措施中最新的一個。夠在40毫秒內(nèi)實現(xiàn)從制動開始到制動恢復(fù)的過程，這個時間是人的反應(yīng)時間得七倍。準(zhǔn)確的行車路線。這個系統(tǒng)已被應(yīng)用于奔馳S600汽車了。汽車安全系統(tǒng)的連續(xù)升級，已經(jīng)產(chǎn)生了一種為保護汽車所有者安全的設(shè)計。穩(wěn)定調(diào)節(jié)系統(tǒng)幫助駕駛員從不可控制的曲線制動中解脫出來，從而避免了汽車的擺。動滑行和交通事故。系統(tǒng)每百萬分之一秒作出一次快速捕捉，以及斷斷汽車是否在按。系統(tǒng)會在瞬間糾正發(fā)動機扭矩或者應(yīng)用汽車左右制動。人的平均反應(yīng)時間的七分之一。安全統(tǒng)計表明，多數(shù)的單車撞擊事故傷亡，事故能夠通過。這項新系統(tǒng)的額外費用主要用于一系列目前汽車日益普遍應(yīng)用的制。博世公司和奔馳公司在過去幾年共同研制的。該系統(tǒng)在博世公司被稱為汽車動力控制。為了檢測出車輛轉(zhuǎn)彎時潛在的危險，DSC系統(tǒng)檢測的是兩前輪在轉(zhuǎn)。過發(fā)動機降速或者單輪制動來減小推動力。

　　

【正文】 ed on a set of LED and photodiodes mounted in the steering wheel. A siliconmicromachine pressure sensor indicates the master cylinder39。s braking pressure by measuring the brake fluid pressure in the brake circuit of the front wheels (and, therefore, the brake pressure induced by the driver). Determining the actual course of the vehicle is a more plicated task. Wheel speed signals, which are provided for antilock brakes/traction control by inductive wheel speed sensors, are required to derive longitudinal slip. For an exact analysis of possible movement, however, variables describing lateral motion are needed, so the system must be expanded with two additional sensors yaw rate sensors and lateral acceleration sensors. A lateral accelerometer monitors the forces occurring in curves. This analog sensor operates according to a damped springmass mechanism, by which a linear Hall generator transforms the spring displacement into an electrical signal. The sensor must be very sensitive, with an operating range of plus or minus g. YAW RATE GYRO At the heart of the latest stability control system type is the yaw rate sensor, which is similar in function to a gyroscope. The sensor measures the speed at which the car rotates about its vertical axis. This measuring principle originated in the aviation industry and was further developed by Bosch for largescale vehicle production. The existing gyro market offers two widely different categories of devices: $6000 units for aerospace and navigation systems (supplied by firms such as GEC Marconi Avionics Ltd., of Rochester, Kent, .) and $160 units for videocameras. Bosch chose a vibrating cylinder design that provides the highest performance at the lowest cost, according to the SAE paper. A large investment was necessary to develop this sensor so that it could withstand the extreme environmental conditions of automotive use. At the same time, the cost for the yaw rate sensor had to be reduced so that it would be sufficiently affordable for vehicle use. The yaw rate sensor has a plex internal structure centered around a small hollow steel cylinder that serves as the measuring element. The thin wall of the cylinder is excited with piezoelectric elements that vibrate at a frequency of 15 kilohertz. Four pairs of these piezo elements are arranged on the circumference of the cylinder, with paired elements positioned opposite each other. One of these pairs brings the open cylinder into resonance vibration by applying a sinusoidal voltage at its natural frequency to the transducers。 another pair, which is displaced by 90 degrees, stabilizes the vibration. At both element pairs in between, socalled vibration nodes shift slightly depending on the rotation of the car about its vertical axis. If there is no yaw input, the vibration forms a standing wave. With a rate input, the positions of the nodes and antinodes move around the cylinder wall in the opposite direction to the direction of rotation (Coriolis acceleration). This slight shift serves as a measure for the yaw rate (angular velocity) of the car. Several drivers who have had handson experience with the new systems in slippery cornering conditions speak of their cars being suddenly nudged back onto the right track just before it seems that their back ends might break away. Some observers warn that stability controls might lure some drivers into overconfidence in lowfriction driving situations, though they are in the minority. It may, however, be necessary to instruct drivers as to how to use the new capability properly. Recall that drivers had to learn not to pump antilock brake systems. Although little detail has been reported regarding nextgeneration active safety systems for future cars (beyond various types of costly radar proximity scanners and other similar systems), it is clear that accidentavoidance is the theme for automotive safety engineers. The most survivable accident is the one that never happens, said ITT39。s Graber. Stability control technology dovetails nicely with the tremendous strides that have been made to the physical structure and overall capabilities of the automobile. The next such safety system is expected to do the same.