FR2810944A1 - Automobile occupant accident protection means operating control system in which driving conditions and driving environment are analyzed to determine probability of impact and to trigger protection - Google Patents

Abstract

The control system (2,3,4) is designed to control the evolvement of trigger steps according to their categories and in time as a function of the impact probability data. The occupant protection means includes occupant retaining belts and impact energy dissipaters (airbags). The occupant protection means uses the following categories: reversible and non careless driving action (R1); reversible and careless driving action (R2); reversible and dangerous driving action (R3); irreversible and non careless driving action (I1); irreversible and careless driving action (I2); irreversible and dangerous driving action (I3).

Description

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  The present invention relates to a function control system

  protection of the occupants of a motor vehicle in the event of an accident. More particularly, the invention relates to a system comprising means for analyzing the driving conditions of the vehicle in its environment in order to deliver information on the probability of impact of the latter over time to means for controlling the protection means

on board the vehicle.

  We have already embarked on board motor vehicles, sensors making it possible to deliver information of this type, these sensors being constituted for example by impact or pre-impact sensors also called

pre-crash sensors.

  For example, document DE-A-1 981 85 86 describes the use of a pre-impact sensor to control the deployment of at least one module to

airbag.

  However, there is a growing integration of protection means on board motor vehicles, and the management of their operation has become extremely complex, which can result in problems of safety on board the vehicle and unnecessary activation of certain

means of protection.

  The object of the invention is to solve these problems.

  To this end, the invention relates to a system for controlling the function-

  protection of the occupants of a motor vehicle in the event of an accident, of the type comprising means for analyzing driving conditions

  of the vehicle in its environment, to deliver probability information

  lity of impact of it over time to means of controlling the function-

  protection means on board the vehicle, characterized in that the protection means are divided into categories of reversible means which are not bothersome for the driving action, - reversible and which are troublesome for the driving action, - reversible and dangerous for driving action, - irreversible and not bothersome for driving action, - irreversible and bothersome for driving action, and irreversible and dangerous for driving action,

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  and in that the control means are adapted to change the thresholds

  triggering of these means according to their category and over time, depending on

  tion of the probability of impact information.

  The invention will be better understood on reading the description which will

  follow, given only by way of example and made with reference to the accompanying drawings, in which: - Fig.1 illustrates the general structure of a control system according to the invention; - Fig.2 shows a table illustrating the distribution of different protection means on board a motor vehicle in different categories;

  - Fig.3 shows a table illustrating a triggering strategy-

  is lying; and - Fig.4 represents a table illustrating the piloting chronology of

  means of protection during an impact.

  FIG. 1 shows a system for controlling the operation of means for protecting the occupants of a motor vehicle

in the event of an accident.

  In fact, this system includes means for analyzing the driving conditions of the vehicle in its environment, which are designated by the general reference 1 in this figure, and which are adapted to deliver information on the probability of impact thereof. over time to means for controlling the operation of the protection means on board the vehicle. These control means are designated by the general reference 2 in this figure and include for example control means 3 of retaining means

  occupants in the vehicle and means for controlling dissimilar means

  energy patterns designated by the general reference 4.

  At the input, these analysis means 1 therefore receive a certain number of information relating to the driving conditions of the vehicle and information delivered by pre-impact sensors designated by the general reference 5

in this figure.

  The information delivered by these sensors can for example relate to information on the obstacle that the vehicle will encounter, such as

  for example the angle of impact, the point of impact, the relative speed, the distance

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  lative, mass, geometry, stiffness, moment of impact, nature of impact

  (human or not, fixed or mobile) and the probability of impact, etc.

  Other information is introduced into these analysis means and is for example available on the vehicle internal information transmission network, such as for example a VAN or CAN network, and relates to

  example the speed of the vehicle, the position of the occupants in it.

  Based on these different input information, these means

  of analysis optimize the triggering of the protection means.

  As mentioned above, these means of protection

  include, for example, retaining means which are used for the promotion

  tection of the occupants of the vehicle and can, for example, comprise various airbag modules of frontal, lateral, knee, ankle, head, etc. types, seat belts, belt pretensioners, retractable pedals and steering columns, active anti-submarine systems,

  active headrests, active covers for pedestrians, etc.

  The energy dissipative means include for example-

  ple different structures to limit the energy dissipated in the vehicle structure, such as for example retractable bumpers, modules to

bumper air bag, etc.

  It can therefore be seen that the system according to the invention makes it possible to control

  the deployment of these different means of protection.

  In an ideal case, if all the information used by the analysis means is perfectly accurate (known obstacle, probability of impact at%, position of the occupants, etc.), the deployment of these different means of protection takes place following a strategy put in place beforehand by the

vehicle manufacturer.

  In reality, all this information is more or less verified due to the fact

  measurement errors and problems identifying obstacles.

  Therefore, the information delivered by the pre-impact sensors to the analysis means is associated with an impact probability rate which takes

account for these uncertainties.

  In the system according to the invention, the deployment of the means of

  occupant protection is governed by this probability of impact.

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  It seems obvious that the deployment strategy should not

  be the same depending on whether the probability of impact is 30% or 95%.

  In the system according to the invention, therefore, a strategy is implemented.

  protection deployment according to the probability of im-

  pact over time delivered by the means of analysis and the nature of these differences

means of protection.

  Indeed, and as illustrated in the table in Figure 2, these

  means of protection are divided into different categories.

  Thus, for example, it is possible to define categories of reversible / irreversible means, which are not bothersome for driving, which are bothersome for

  driving or dangerous for driving the vehicle.

  The occupant restraint means and energy dissipative means can therefore be classified in the form of: - reversible means, that is to say capable of returning to its initial state after deployment, - irreversible means, that is to say incapable to return to its initial state after deployment, - means which are not bothersome for the driving action of the vehicle, that is to say having no impact on the driving action,

  - inconvenient means for driving action, i.e. disrupting driving

  tion of driving and being able to present a potential risk of accident, and dangerous means for the action of driving, ie preventing

  driving action and being very harmful to it.

  Thus, for example, in this table, different retaining means and different energy dissipating means are illustrated and classified according to

such a distribution.

  In this regard, it should be noted that irreversible means present the

  agrees to require significant repair costs after deployment,

  hence the advantage of deploying them only in cases of extreme necessity.

  We then define the following six categories of means or systems: Category R1: Reversible and non-annoying system for driving action, - Category R2: Reversible and annoying system for driving action, Category R3: Reversible and dangerous system for driving action, Category II: Irreversible and non-annoying system for driving action, - Category 12 Irreversible and annoying system for driving action,

  - Category 13 Irreversible and dangerous system for driving action.

  The following actions are also defined: Action A authorization to deploy the system, Action B placing the system on alert, lowering the deployment thresholds

  lying at its lowest point and deploying if the impact is confirmed by accelerating

  central meter of the vehicle. In the case where a means of protection must be de-

  bent before impact to be effective, it remains inactive.

  Action C: system alert, moderate lowering of thresholds

  deployment so as to be able to confirm or refute the identification of the obstacle

  key and deployment if there is confirmation by the central accelerometer of the vehicle, Action D: the information from the pre-impact sensors is not taken into account

  account, the thresholds are preserved and deployment is only authorized if the acceleration

  central rometer of the vehicle delivers information exceeding the threshold of

deployment.

  Concerning actions B, C and D, if a means of protection must be

  deployed before the shock to be effective, it remains inactive.

  The table in Figure 3 illustrates the different actions taken to

  each category of means and according to the probability of impact.

  The information delivered by the pre-impact sensors is used

  from the time before the collision is 150 milliseconds

for example.

  During this time, these sensors still provide information

  which allow to refine the diagnosis and therefore the probability of impact.

  Depending on the evolution of the probability of impact, the strategy for

  triggering therefore evolves according to the table in this figure 3.

  By way of example, FIG. 4 illustrates the chronology of such a

  impact during the 150 milliseconds preceding this one.

  To illustrate this, we can take an example of a front-front impact of a vehicle A against a vehicle B and that the vehicle A has such a structure and means of protection comprising means for retaining the occupants formed by a pretensioner pyrotechnic, category 12, one module

  driver's airbag, category 13, and an esca- bumper

  electromechanical motable, category R1.

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  If we assume that the driver is alone in the vehicle and well-

  located on the seat, the protection strategy in this type of shock is therefore the triggering of the pyrotechnic pretensioner, the airbag module

  driver and retractable electromechanical bumper.

  According to this scenario, we then have the following deployment chronology: 150 ms before the impact: the electromechanical retractable bumper

  is inactive and the deployment threshold for the pre-

  pyrotechnic tensioner and the driver's airbag module.

  - 100 ms before the shock: the retractable electromechanical bumper is still inactive and the deployment thresholds of the pyrotechnic pretensioner

  and the driver's air bag module are always lowered

Deree.

  - 50 ms before the shock: we authorize the triggering of the bumper es-

  electromechanical jacket, the deployment thresholds for the pyrotechnic pretensioner and the driver's airbag module remaining lowered by

moderately.

  - 5 ms before the shock: the deployment thresholds are lowered to the lowest

  for the pyrotechnic pretensioner and the driver's air bag module. It is therefore conceivable that such a structure has a certain number of advantages insofar as it makes it possible to implement a deployment strategy making it possible to optimize the operation of the means of protection of the occupants of the vehicle, while avoiding no triggers

necessary of these.

  It goes without saying of course that different embodiments of this

system can be considered.

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Claims (2)

  1. System for controlling the operation of means of protection of the occupants of a motor vehicle in the event of an accident, of the type comprising   means (1) for analyzing the driving conditions of the vehicle in its surroundings   Reason, to deliver information on the probability of its impact over time to means (2,3,4) for controlling the operation of the protection means on board the vehicle, characterized in that the protection means are divided into categories of means: reversible and not bothersome for the driving action (R1), - reversible and bothersome for the driving action (R2), - reversible and dangerous for the driving action (R3), - irreversible and not bothersome for the driving action (11), - irreversible and bothersome for the driving action (12), and - irreversible and dangerous for the driving action (13), and in that the means of command (2,3,4) are adapted to change the trigger thresholds of these means according to their category and in the   time, based on impact probability information.   2. System according to claim 1, characterized in that the means for protecting the occupants of the vehicle comprise means for retaining   these and dissipative means of impact energy.