CN201066322Y - A braking stability detection device based on the car joint braking system - Google Patents

Abstract

A braking stability detecting device based on an automotive associated braking system is mainly composed of a steering wheel turning angle sensor (1), a yaw rate sensor (2), a sideward acceleration sensor (3), a vehicle speed sensor (4), a manual switch (5), a power supply (6), a controller ECU (7), an alarm (8) and an indicator light (9). Wherein, the signals are input signals, which are generated by the steering wheel turning angle sensor (1), the yaw rate sensor (2), the sideward acceleration sensor (3), the vehicle speed sensor (4) and the manual switch (5), are connected with the controller ECU (7), and the alarm (8) and the indicator light (9), which are regarded as the output signals of the device, are also connected with the controller ECU (7). The utility model utilizes the two variables - the automotive sideslip angle and the yaw rate-together to judge the braking stability of the automotive associated braking system.

Description

A kind of insensitivity pick-up unit based on the automobile associated braking system

Technical field

The utility model belongs to automobile brake judgement of stability field, and what be specifically related to is a kind of insensitivity pick-up unit based on the automobile associated braking system.

Background technology

Along with the Hyundai Motor travelling speed is more and more faster, the brake load of automobile is also increasing, frequently or for a long time uses running brake, phenomenons such as friction disc is overheated, brake efficiency heat fading can occur.In order to alleviate the load of foundation brakes (friction brake), increasing commercial car has installed auxiliary brake additional.The associated braking system of automobile is exactly this brake system of being made up of foundation brakes and auxiliary brake.Wherein auxiliary brake mainly contains Retarder, current vortex retarder, engine brake, engine exhaust and brake and engine braking etc.

The insensitivity of automobile is meant that automobile is kept straight line in braking procedure or by the ability of predetermined negotiation of bends.The phenomenon of brake side-slipping and wheel side sliding whipping may appear in the bad automobile of insensitivity.The brake side-slipping majority of automobile is because undesired the causing of technology status of automobile can be eliminated through maintenance and adjustment; And the sideslip phenomenon that takes place during automobile brake remove have with the structural behaviour of automobile own outside the Pass, also relevant with other factors such as road conditions.It is the most dangerous situation that trailing wheel sideslip phenomenon appears in the automobile high-speed service brake, because the irregular gyration of the normal generation of automobile at this moment makes automobile partially or even wholly out of hand.Therefore along with the raising of the Hyundai Motor speed of a motor vehicle, the sideslip of trailing wheel becomes the key factor that influences traffic safety during automobile brake.

Because the braking moment of auxiliary brake acts on the driving wheel of automobile, changed the distribution of original damping force, variation has taken place in the insensitivity of automobile thereupon, can aggravate stability change when particularly travelling under complex road conditions such as road surface of hanging down attachment coefficient or bend.Automobile generation unstability is the inelastic region at tire mostly, and promptly the side force that produces along with the increase tire of side drift angle is saturated gradually.Current axis takes place that front axle just breaks away easily when saturated, makes vehicle depart from driver's expected trajectory; When rear axle takes place saturated and is easy to generate more dangerous operating mode such as whipping when breakking away.

It is generally acknowledged that the yaw velocity of automobile and the side slip angle of automobile are the important parameters of describing motion state of automobile, they have characterized the stability of automobile from different sides.The gain of the yaw velocity of automobile and steering wheel angle can characterize the stability of automobile under the very little situation of the side slip angle of automobile, but same gain has just lost meaning to the sign of stability of automobile when the side slip angle of automobile is very big.The yaw velocity of automobile automobile under the situation that racings such as whipping take place just can not embody the track of automobile, also just can not characterize the stability of automobile.The side slip angle of automobile is often all bigger during automobile generation stability problem.The yaw velocity and the side slip angle of automobile intercouple again, and present method is the stability that single dependence yaw velocity or side slip angle are judged automobile mostly, and this obviously can not judge the stability of automobile very accurately.

Summary of the invention

Judge the deficiency of stability of automobile in order to detect the insensitivity that installed the later automobile associated braking system of auxiliary brake additional and single dependence yaw velocity or side slip angle, the utility model provides a kind of insensitivity pick-up unit based on the automobile associated braking system.

The utility model adopts following technical scheme: it is made up of steering wheel angle sensor 1, yaw-rate sensor 2, side acceleration sensor 3, vehicle speed sensor 4, hand switch 5, power supply 6, controller ECU7, alarm 8 and relay indicating light 9.Take hand switch to be used for starting and closing this device, be provided with relay indicating light in order to show this device duty.The signal that steering wheel angle sensor 1, yaw-rate sensor 2, side acceleration sensor 3, vehicle speed sensor 4, hand switch 5 produce links to each other with controller ECU7, as input signal, alarm 8 also links to each other with controller ECU7 with relay indicating light 9, is the output signal of this device.

The method of judging automobile brake stability is as follows:

The side slip angle β of automobile uses by side acceleration a _y, speed of a motor vehicle u and yaw velocity

Carrying out automobile side angle speed v and automobile longitudinal speed that integral and calculating comes out estimates.

$\mathrm{\β}=\arctan \left|\frac{v}{u}\right|$

When β satisfies as lower inequality

$|c_1\mathrm{\β}+c_2\stackrel{g}{\mathrm{\β}}|\≤1---\left(1\right)$

Think that the state of automobile is stable, otherwise be unsettled.

c ₁, c ₂-constant.

By the yaw velocity of relatively measuring by yaw-rate sensor

With the nominal yaw velocity that calculates by linear two-freedom model

Difference

Satisfy following condition

Think that the state of automobile is stable, otherwise be unsettled.

The a-constant.

Description of drawings

Fig. 1 system chart of the present utility model.

1-steering wheel angle sensor 2-yaw-rate sensor 3-side acceleration sensor

4-vehicle speed sensor 5-hand switch 6-power supply 7-controller ECU 8-alarm

The 9-relay indicating light

The program flow diagram that Fig. 2 insensitivity of the present utility model is judged.

Concrete form of implementation

As shown in Figure 1, controller ECU7 gathers the signal of steering wheel angle sensor 1, yaw-rate sensor 2, side acceleration sensor 3, vehicle speed sensor 4 in real time.Through analysis and the judgement of controller ECU7, alarm 8 is arranged again as output.With output signal 1 (high level) expression alarm work is the state labile of automobile; Not working with output signal 0 (low level) expression alarm is that the state of automobile is stable.The method that controller ECU7 analyzes: the difference of judging yaw velocity and nominal yaw velocity earlier is in the scope that requires, if not, think that then vehicle condition is unsettled, alarm 8 work; If, judge again whether the side drift angle of the barycenter of automobile satisfies formula (1), if satisfy, think that then the state of automobile is stable, alarm 8 is not worked; Otherwise think that the state of automobile is unsettled, alarm 8 gives the alarm.

Claims (1)

1. insensitivity pick-up unit based on the automobile associated braking system, it is characterized in that the signal that steering wheel angle sensor (1), yaw-rate sensor (2), side acceleration sensor (3), vehicle speed sensor (4), hand switch (5) generation are set links to each other with controller ECU (7), as input signal, alarm (8) also links to each other with controller ECU (7) with relay indicating light (9), as the output signal of this device.

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