Method for crash testing a motor vehicle

A method for crash testing a motor vehicle is disclosed. The method provides a crash test routine where an inflatable restraint is deployed using a single deployment pattern throughout at least one government regulation zone. This helps to prevent overlap of a transition zone and can help make the deployment of the inflatable restraint more predictable. This can increase occupant safety and simply testing.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to the field of motor vehicle restraint systems, and more particularly, to a method for crash testing a motor vehicle.

2. Related Art

Currently, some cars, trucks and vans provide some kind of supplemental restraint system (SRS). Often, these supplemental restraint systems take the form of inflatable devices or restraints. In some cases, airbags are used. The following related art references provide a general background of the field.

Cooper (U.S. Pat. No. 6,696,933) discloses an air bag system with a biomechanical grey zone. The biomechanical grey zone is an attempt to comply with recent legislative changes that require airbags to restrain women and children as well as adult males. To help restrain women and children, Cooper proposes the use of a system where air bags include multi-level inflators that can adjust the inflation characteristics of the air bag. The biomechanical zone is defined as a region where it is acceptable to deploy the air bag using either a low power inflator or a high power inflator. While the use of biomechanical grey zones may help to comply with new governmental requirements, the grey zones introduce uncertainty in the deployment characteristics of the air bag and this makes system design and testing difficult. The Cooper reference is incorporated by reference in its entirety.

Corrado et al. (U.S. Pat. No. 6,249,729) teaches an occupancy sensing system for an automobile. The system is used in conjunction with an airbag deployment system to determine the nature, location and motion parameters of an occupant within the vehicle interior. These parameters are determined by ultrasound and/or infrared sensors. The system establishes criteria for airbag disablement or for modified airbag deployment based on sensor information. In particular, Corrado teaches the use of a Keep Out Zone (KOZ) within the vehicle interior relative to the dashboard or instrument panel. Analyzing the relative location of an occupant with respect to the Keep Out Zone can be used to determine whether the airbag deployment is disabled or modified.

Wang et al. (U.S. Pat. No. 6,662,092) teaches a control method for deploying an air bag using fuzzy logic. Wang attempts to provide a fuzzy logic deployment system that is more direct than previous fuzzy logic systems and where the calibration process if more user friendly. The method uses a deployment control algorithm to determine whether certain stages are deployed based on certain thresholds related to predicted occupant movement and crash severity.

There is currently a need for a way to increase the predictability of the deployment of an inflatable restraint to improve occupant safety and to simplify the process of crash testing the motor vehicle.

SUMMARY OF THE INVENTION

A system and method for crash testing a motor vehicle is disclosed. The invention can be used in connection with a motor vehicle. The term “motor vehicle” as used throughout the specification and claims refers to any moving vehicle that is capable of carrying one or more human occupants and is powered by any form of energy. The term motor vehicle includes, but is not limited to cars, trucks, vans, minivans, SUV's, motorcycles, scooters, boats, personal watercraft, and aircraft.

Generally, the related art teaches systems and methods for a single deployment event and focus on correctly making a single deployment decision. In contrast, one aspect of the present invention is directed to providing a novel deployment map that applies to a number of different deployment scenarios and conditions. This novel map can help improve the predictability of a deployment of an inflatable restraint, and this predictability can help designers and engineers improve occupant safety over a wide range of different collision scenarios and conditions. In another aspect, the present invention is directed to a method of qualifying a motor vehicle to use the novel deployment map.

In another aspect, the invention provides a method of deploying an inflatable restraint wherein a single deployment pattern is used throughout at least one government regulation zone.

In another aspect, a single deployment pattern is used throughout every government regulation zone.

In another aspect, the government regulation zone extends from 32 km/h to 40 km/h.

In another aspect, the single deployment pattern is a delayed deployment pattern.

In another aspect, a second government regulation zone extends from 0 km/h to 48 km/h.

In another aspect, a second deployment pattern is used throughout the second government regulation zone.

In another aspect, a second deployment pattern is substantially similar to the single deployment pattern.

In another aspect, the invention provides a method of deploying an inflatable restraint having at least one transition zone is disposed between a first deployment pattern and a second deployment pattern; wherein the transition zone includes probabilities of deploying the inflatable restraint using either the first deployment pattern or the second deployment pattern; and wherein a government regulation zone is separated from every transition zone.

In another aspect, the transition zone includes a lower end and an upper end and wherein the government regulation zone includes a lower end and an upper end; and wherein the upper end of the transition zone is less than the lower end of the government regulation zone.

In another aspect, the second deployment pattern is a delay deployment pattern.

In another aspect, first deployment pattern is a no deploy pattern.

In another aspect, a first crash test validates the results for an entire government regulation zone.

In another aspect, the first crash test is conducted at a speed corresponding to an upper end of the government regulation zone.

In another aspect, the invention provides a method of simultaneously deploying an inflatable device comprising the steps of: determining that a first charge configured to inflate the inflatable device; deploying the inflatable device using the first charge; providing a delay; determining whether a second charge configured to inflate the inflatable device should be deployed; and using the second charge in conjunction with the first charge if the inflatable device should be deployed.

In another aspect, the second charge has less power than the first charge.

In another aspect, the delay is about 0 to 10 milliseconds.

In another aspect, the delay is about 5 milliseconds.

In another aspect, information from a sensor is retrieved during the delay.

In another aspect, an additional computation is made during the delay.

In another aspect, the step of determining whether a second charge configured to inflate the inflatable device should be deployed, is made during the delay.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

FIG. 1is a flow diagram of a preferred embodiment of a method of improving a crash test regiment for a motor vehicle. The method shown inFIG. 1can include the following steps. The method begins with step102where a new firing map is designed. This new firing map helps to simplify the firing conditions of an inflatable restraint and reduce occupant injury. The simplified algorithm or firing map can help make the deployment conditions of the inflatable restraint more predictable and this helps to provide a supplemental restraint system that is more reliable and easier to test. This predictability also helps designers improve occupant safety. Another benefit of the new firing map is that it can help reduce the number of vehicles required to comply with government-mandated crash tests. In some cases, this reduction is substantial.

After the new firing map has been designed, the method can proceed to step104where a motor vehicle is qualified for using the new firing map. In step104, the process helps to identify which motor vehicles can accept the new map and can also help tune or modify a motor vehicle so that it can become a motor vehicle capable of using the new firing map.

After the motor vehicle has been qualified to use the new firing map, the motor vehicle is then subjected to a simplified crash test routine in step106. Preferably, step106includes the process of actually conducting real world crash tests with actual motor vehicles and crash test dummies.

FIG. 2is a schematic diagram of a conventional firing map200for an inflatable restraint. The conventional firing map200includes three deployment scenarios depending on the type of impact. The three types of impact are a conventional flat barrier scenario202, a conventional angled barrier scenario204and a conventional offset barrier scenario206. In each of the scenarios, the conventional firing map200also deploys the inflatable restraints differently depending on the speed of the impact. Generally, conventional firing map200considers the speed of the impact and the type of impact to determine how or if the inflatable restraint is deployed.

In the conventional flat barrier scenario202, conventional firing map200includes three different deployment options, which are related to corresponding regions in the bar graph representing conventional flat barrier scenario202. The first deployment option is a no fire option and this first option occurs in region208. A second deployment option is a delay fire option, and this second option occurs in region210. The third deployment option is a simultaneous fire option that occurs in region212.

Generally, inflatable restraint systems can include two charges, a low power charge and a high power charge. The high power charge is generally designed to provide a low energy deployment that is suitable for smaller and less massive occupants, for example, a woman with physical characteristics similar to an AF5% crash test dummy. The low power charge is generally used to supplement the energy of the high power charge, and when these two charges are deployed simultaneously, they produce a high energy deployment that is suitable for larger and more massive individuals, for example, a male with physical characteristics similar to an AM50% crash test dummy.

A delay deployment can be conducted in many different ways. The system can delay deploying the inflatable restraint in the following ways: the system can immediately deploy the high power charge and delay deploying the low power charge, the system can delay first and then deploy the two charges simultaneously, or the system can deploy the low power charge immediately and delay deploying the high power charge. In a simultaneous deployment, the system deploys both the low power charge and the high power charge at the same time to inflate the restraint very quickly.

In some embodiments, a simultaneous deployment can include a slight delay. In these embodiments, the high power charge is initially deployed, and then a slight delay is provided. This delay can be used to provide the system with a little more time to decide whether to deploy the second low power charge. In some cases, the system has determined that the high power charge needs to be deployed. The slight delay can be used to retrieve information from other sensors or perform other computations. These steps can be used by the system to decide whether to also deploy the low power charge. This slight delay can range from about 0 to 10 milliseconds and in an exemplary embodiment, the delay is about 5 milliseconds.

The conventional firing map200includes transition zones between two adjacent deployment regions. Considering conventional flat barrier202, a first transition zone214is disposed between first region208and second region210. This first transition zone214is bounded, on the low speed end, at about 13 km/h and on the high speed end at about 19 km/h.

This first transition zone214determines the deployment characteristics for the inflatable restraint where the passenger or driver is unbelted. First transition zone214graphically represents the percentage chance between first region208and second region210. In conventional map200, first region208corresponds to a no fire condition and second region210corresponds to a delay fire condition. Thus, first transition zone214graphically represents the percentage chance that the inflatable device will either not deploy (no fire) or will deploy in a delay mode.

As shown inFIG. 2, at the low end of first transition zone214, the bar graph representing the conventional flat barrier scenario202is almost completely represented by first region208. This means that there is almost a 100% chance that the deployment condition associated with first conventional region208will occur. Since first conventional region208represents a no fire condition, there virtually no chance that the inflatable device will deploy at the low end of first transition zone214.

At the opposite end of first transition zone214, at about 19 km/h, the bar graph representing first scenario202is almost completely represented by second region210. Since second region210corresponds to a delay fire condition, it is virtually assured that inflatable restraint will deploy in a delay fire mode. At speeds between 13 km/h and 19 km/h, there is a generally linear relationship between speed and the likelihood that the inflatable device will be deployed in a delay mode. Generally, as speed increases, it becomes more and more likely that the inflatable restraint will be deployed in a delay mode.

Conventional flat barrier scenario202also includes a second transition zone216. This second transition zone216extends from a low end of about 13 km/h to a high end of about 26 km/h. In order to accurately show first transition zone214,FIG. 2shows only a portion of second transition zone216, the slope of which should continue until 13 km/h. This second transition zone relates to a belted occupant, either driver or passenger. Second transition zone216provides the probability that the inflatable device will either not deploy or will deploy in a delay mode. Again, like first transition zone214, the percentage chance of either a no fire condition or a delay fire condition is graphically related to ratio of the first region208compared to the second region210at a given speed.

Conventional flat barrier scenario202includes a third transition zone218. This third transition zone218is disposed between second region210and third region212and provides the percentage chance of either a delay mode deployment or a simultaneous deployment.

Third transition region starts at about 30 km/h and extends to about 37 km/h. Similar to the first and second transition regions, third transition region218provides a percentage chance that the inflatable device will deploy in accordance with the pattern associated with second region210or third region212. Recall that second region210is associated with a delay fire condition and third region212is associated with a simultaneous fire condition. Because of these associations, third transition zone218graphically represents the percentage chance that an inflatable device will deploy in a delay fire mode or a simultaneous fire mode.

As shown in conventional flat barrier scenario202, the percentage chance that the inflatable device will deploy in a simultaneous fire mode increases as the speed of the impact increases. At about 37 km/h, it is a virtual certainty that the inflatable device will deploy in a simultaneous mode and at speeds above 37 km/h, the inflatable device is designed to deploy in simultaneous mode.

Conventional angle barrier scenario204includes three regions, first region208, second region210and third region212corresponding to three different deployment patterns for an inflatable restraint. Conventional angle barrier scenario204includes a fourth transition zone220disposed between first region208and second region210. Fourth transition zone220extends from a low end of about 13 km/h to a high end of about 19 km/h.

Fourth transition zone220is similar to first transition zone214. As shown inFIG. 2, at the low end of fourth transition zone220, the bar graph representing the angle barrier scenario204is almost completely represented by first conventional region208. This means that there is almost a 100% chance that the deployment condition associated with first conventional region208will occur. Since first conventional region208represents a no fire condition, there virtually no chance that the inflatable device will deploy at the low end of fourth transition zone220.

At the opposite end of fourth transition zone220, at about 19 km/h, the bar graph representing second scenario204is almost completely represented by second region210. Since second region210corresponds to a delay fire condition, it is virtually assured that inflatable restraint will deploy in a delay fire mode. At speeds between 13 km/h and 19 km/h, there is a generally linear relationship between speed and the likelihood that the inflatable device will be deployed in a delay mode. Generally, as speed increases, it becomes more and more likely that the inflatable restraint will be deployed in a delay mode.

Conventional angle barrier scenario204also includes a fifth transition zone222disposed between second region210and third region212. This fifth transition zone222extends from a low end of about 26 km/h to a high end of about 32 km/h and provides the percentage chance of either a delay mode deployment or a simultaneous deployment.

Fifth transition zone222starts at about 26 km/h and extends to about 32 km/h. Similar to other transition zones, fifth transition zone222provides a percentage chance that the inflatable restraint will deploy in accordance with the pattern associated with second region210or third region212. Recall that second region210is associated with a delay fire condition and third region212is associated with a simultaneous fire condition. Because of these associations, fifth transition zone222graphically represents the percentage chance that an inflatable restraint will deploy in a delay fire mode or a simultaneous fire mode.

As shown in conventional angle barrier scenario204, the percentage chance that the inflatable device will deploy in a simultaneous fire mode increases as the speed of the impact increases. At about 32 km/h, it is virtual assured that the inflatable restraint will deploy in a simultaneous mode and at speeds above 32 km/h, the inflatable restraint is designed to deploy in simultaneous mode.

Conventional offset barrier scenario206includes two regions, first region208and second region210. Conventional offset barrier scenario206does not include a third region. Sixth transition zone224is disposed between first region208and second region210. Sixth transition zone224is larger than some other transition zones and extends from about 26 km/h to about 40 km/h.

As shown inFIG. 2, at the low end of sixth transition zone224, the bar graph representing the offset barrier scenario206is almost completely represented by first conventional region208. This means that there is almost a 100% chance that the deployment condition associated with first conventional region208will occur. Since first conventional region208represents a no fire condition, there virtually no chance that the inflatable restraint will deploy at the low end of sixth transition zone224.

At the opposite end of sixth transition zone224, at about 40 km/h, the bar graph representing offset barrier scenario206is almost completely represented by second region210. Since second region210corresponds to a delay fire condition, it is virtually assured that inflatable restraint will deploy in a delay fire mode. At speeds between 26 km/h and 40 km/h, there is a generally linear relationship between speed and the likelihood that the inflatable device will be deployed in a delay mode. Generally, as speed increases, it becomes more and more likely that the inflatable restraint will be deployed in a delay mode.

Government rules generally require motor vehicles to undergo crash testing at certain speeds and under certain conditions. Currently, there are two government regulation zones, a first regulation zone between 32 km/h to 40 km/h for unbelted occupants and a second regulation zone between 0 km/h and 48 km/h for belted occupants. Motor vehicles sold in the United States must be subjected to a number of crash tests to establish passenger and occupant safety in these regulation zones in the event of a collision.

While transition zones have been used in the past as a way to decide how to deploy an inflatable restraint, they also introduce a number of problems. Deployments that occur within transition zones are unpredictable because the transition zones only provide percentage chances of two competing deployment conditions. In some cases, the response of a system using conventional firing map200is so unpredictable that it is possible for an inflatable restraint to deploy two different ways in two successive and identical crash tests.

Because the deployment of an inflatable restraint is unpredictable in a transition zone, the system must be tested at the government mandated speeds as well as at all endpoints of the transition zone.

In order to minimize the number of crash tests, engineering reasoning is generally used and a worst case scenario is tested. Using engineering reasoning, if a motor vehicle passes a crash test conducted under the worst case, then it can be assumed that the motor vehicle will also pass a crash test at under less severe conditions. This is one way to validate the response of the system under many different possible conditions. For example, if a motor vehicle passed a crash test at 40 km/h, engineering reasoning dictates that the same motor vehicle, identically prepared and equipped, should pass the same crash test at 35 km/h. In fact, the motor vehicle should also pass the same crash test at any speed between 0 and 40 km/h.

Referring toFIG. 4, which is an embodiment of a table of crash tests for conventional firing map200, andFIG. 2, the crash tests that are required can be observed. The crash tests are preferably conducted in sets, and each set preferably includes a driver and a passenger. Set1is conducted at a speed of 37 km/h and with a flat barrier collision condition. Set1is used to test the occupant safety of a typical female and an AF5% crash test dummy (which stands for American Female 5 percentile) can be used to model the behavior of a hypothetical female occupant. Set1is an unbelted test, meaning seat belts are not used during the test.

Set2is similar to set1except that set2is used to test the occupant safety of a typical male and an AM50% crash test dummy (which stands for American Male, 50 percentile) can be used to model the behavior of a hypothetical male. The conditions and attributes of the remaining eleven sets of crash tests are self-explanatory from the table shown inFIG. 4.

FIG. 3is a schematic diagram of a preferred embodiment of firing map300. It has been discovered that with careful design of motor vehicle100, the simultaneous fire mode is not necessary to provide occupant safety and also meet government crash test requirements. In other words, it is possible to use a delay fire mode to meet government crash test requirements under conditions where conventional systems use a simultaneous fire mode.

This discovery can be used to create a firing map300that is less complex than conventional firing map200. It is believed that this discovery will help to improve occupant safety because the reduction in the complexity of the new firing map300compared to the conventional firing map200can provide more predictable deployments of inflatable devices. This improved predictability can, in turn, be used to better understand the interplay between occupants and the inflatable restraint system at various different speeds and collision conditions. This can help engineers design safer motor vehicles and inflatable restraint systems. As a side benefit, this discovery also allows the locations of the various transition zones to be selected to prevent overlap with one or more government regulation zones.

Also, because a simultaneous fire mode is no longer required, this entire deployment mode can be omitted from firing map300. In the embodiment shown inFIG. 4, firing map300does not include a simultaneous deployment or firing condition. Firing map300includes just two deployment patterns, a no fire mode and a delayed deployment mode.

Preferably, the various transition zones are carefully selected so that none of the transition zones overlaps a regulation zone. In one embodiment shown inFIG. 3, the transition zones have been moved away or separated from the regulation zones. This allows the crash test routine to be greatly simplified. Referring toFIG. 5, which is a table of crash tests corresponding to firing map300reflected inFIG. 3, differences between this table and the table shown inFIG. 4are readily apparent.

As shown inFIG. 5, several crash tests are no longer needed. Set1is no longer needed because set3is conducted at 40 km/h under the same conditions, namely in delay mode. Note the arrows indicating that new set3is conducted in delay mode from the previous no delay mode. As discussed earlier, if a motor vehicle passes a crash test at a higher speed, then it can be assumed that the motor vehicle will pass the same crash test at a lower speed. Because the new firing map300uses the same deployment conditions at 40 km/h and 37 km/h, any motor vehicle using new firing map300that passes the 40 km/h crash test should also pass set1as well. For the same reasons, sets2,5,6and12are no longer required.

Returning toFIG. 1, some embodiments include provisions104to determine if a motor vehicle is qualified to use new firing map300. Although many different methods can be used to determine if a motor vehicle is qualified to use new firing map300, the following method is preferred. Referring toFIG. 6, which is a flow diagram of a preferred embodiment of a method104for determining if a motor vehicle is qualified to use new firing map300, this method can both determine if a motor vehicle is qualified to use new firing map300and also help modify or “tune” the motor vehicle so it becomes qualified to use new firing map300.

Method104can include a number of different tests and a number of modifications that can be made to help the motor vehicle to pass those tests. Preferably, these tests and modifications are arranged sequentially within method104in a systematic way so that a modification does not invalidate previous test results.

Preferably, method104begins with first test602. In first test602, the relative position of a hypothetical child with respect to a No Good Zone (“NGZ”)1002is considered. In some cases, a C3Y (child, three year old) and/or C6Y (child, six year old) dummy is used to model the hypothetical child. Referring toFIG. 10, NGZ1002is a zone roughly between inflatable restraint lid1004and windshield1006. In some embodiments, NGZ1002is defined using particular relative offsets and spacing from various components.

In a preferred embodiment, NGZ1002is defined by one or more boundaries. These boundaries are preselected or predefined distances from various objects or lines. In the embodiment shown inFIG. 10, inflator module1020includes an inflator center line1022. In some embodiments, a boundary is established based on inflator center line1022. In the embodiment shown inFIG. 10, inflator center line boundary1026is defined as a boundary that is parallel and spaced from inflator center line1022. The distance can be varied, however, any distance of about 30 mm to 200 mm can be used. In an exemplary embodiment, inflator center line boundary1026is disposed about 70 mm away from inflator center line1020towards or into the passenger cabin of motor vehicle100.

Inflator module1020can also include an edge1024. In some embodiments, a boundary is established based on inflator edge1024. In the embodiment shown inFIG. 10, inflator edge boundary1028is defined as a boundary that is vertical and horizontally spaced from inflator edge1024. The distance can be varied, however, any distance of about 30 mm to 200 mm can be used. In an exemplary embodiment, inflator edge boundary1028is disposed about 70 mm away from inflator edge1024towards or into the passenger cabin of motor vehicle100.

In some embodiments, a boundary can be established based on windshield1006. In the embodiment shown inFIG. 10, windshield boundary1030is defined as a boundary that is roughly parallel to windshield1006. The distance between windshield1006and windshield boundary1030can be varied, however, any distance of about 50 mm to 300 mm can be used. In an exemplary embodiment, windshield boundary1030is disposed about 100 mm away from windshield1006towards or into the passenger cabin of motor vehicle100.

In some embodiments, a boundary can be established based on inflator lid1004. In the embodiment shown inFIG. 10, the arc or range of motion of the inflator lid is indicated by1004. A lid boundary1032is defined as a locus of points equally spaced from arc1004and disposed outward or away from inflator module1020. The distance between inflator lid1004and lid boundary1032can be varied, however, any distance of about 1 mm to 50 mm can be used. In an exemplary embodiment, lid boundary1032is disposed about 10 mm away from arc1004towards or into the passenger cabin of motor vehicle100.

One or more of these various different boundaries can be used to establish NGZ1002. In an exemplary embodiment, shown inFIG. 10, all of the above boundaries are used. However, other embodiments may use more or less boundaries to establish NGZ1002.

Referring toFIG. 6, if the hypothetical child passenger is clear of NGZ1002, then the process moves on to step606. However, if the hypothetical child passenger does not clear NGZ1002, then the process moves to step604.

FIG. 7is an enlarged view of step604, and one or more of the modifications shown inFIG. 7can be made to help motor vehicle100pass first test602. One option is to modify the Instrument Panel (IP)1008shape. The shape of IP1008can be extended into the passenger cabin to help prevent entry of the hypothetical child in to NGZ1002. Another option is to modify the shape of first thigh bolster or first contact point. Another option is to modify the passenger seat height and/or angle. One or more of these options can be used to prevent the hypothetical child occupant from entering NGZ1002.

Some of these modifications can be seen inFIG. 13, which is a schematic diagram of a motor vehicle interior and an out of position child1302. Motor vehicle interior includes a seat1304. The forward edge1306of seat1304generally serves as the first contact point for child1302. As shown schematically inFIG. 13, the location of forward edge1306and/or the angle of seat1304can be modified to help motor vehicle100pass first test602.

After these modifications are made, the process returns to first test602until it has been confirmed that the hypothetical child does not enter NGZ1002.

After this has been confirmed, the process moves on to step606, the second test, where the process determines whether or not the kinematic arc of an average male passenger will strike windshield1006.FIGS. 11 and 12are schematic diagrams of examples demonstrating contact with windshield1006and clearance of windshield1006, respectively. In some cases, an AM50% crash test dummy (which stands for American Male, 50 percentile) is used in second test606. Referring toFIG. 11, crash test dummy1100is in a first position1102prior to the collision and is in a second position1104after the collision. As shown inFIG. 11, crash test dummy1100contacts windshield1006in second position1104. It can also be observed that the pelvis1105of crash test dummy1100moves from a first position1106to a second position1107as indicated by arrow1112causing an excessive pelvic stroke during the collision. Both of these incidents are not desirable and would cause the design shown inFIG. 11to fail second test606.

Because the motor vehicle failed second test606, the process would move to step608where stage two modifications can be made.FIG. 8is an enlarged view of step608, and fromFIG. 8, there are preferably three available stage two modifications that can be made. The Knee Bolster (K/B)1108can be moved; the windshield1106can be moved forward and away from the occupant; and finally the stiffness of knee bolster1108can be adjusted. One or more of the stage two modifications can be made, and eventually the goal is to design the motor vehicle to pass second test606.

FIG. 12is a preferred embodiment of an example of a motor vehicle that passes second test606. InFIG. 12, crash test dummy1200moves from a first position1202prior to the collision to a second position1204after the collision. It can be observed inFIG. 12, that crash test dummy1200clears windshield1006and no head contact with windshield1006occurs. It can also be observed that re-designed knee bolster1208helps to manage the motion of pelvis1206to acceptable levels.

After motor vehicle100passes second test606, the process proceeds to third test610where an Out Of Position (OPP) child passenger is tested with a delayed firing inflatable restraint. In a preferred embodiment, the firing delay is about 20 to 30 milliseconds. Again, like other tests, a C6Y (child, six year old) dummy can be used for third test610. If motor vehicle100fails third test610, then the process moves to step612, where stage three modifications, including tuning the passenger side inflatable restraint can be made. After the inflatable restraint has been tuned, the process returns to third test610. Preferably, this is done until motor vehicle100passes third test610.

After motor vehicle100passes third test610, the process moves on to fourth test614. Fourth test614determines whether motor vehicle100can protect occupants during a frontal 40 km/h collision who are not wearing their seat belts. Preferably, both a hypothetical male occupant and a hypothetical female occupant are tested in fourth test614. In some embodiments, an AM50% crash test dummy (which stands for American Male, 50 percentile) is used to model the behavior of a hypothetical male and an AF5% crash test dummy (which stands for American Female 5 percentile) is used to model the behavior of a hypothetical female occupant.

If motor vehicle100fails fourth test614, then the process moves to step616where stage four modifications can be made.FIG. 9is an enlarged view of step616. Preferably, stage four modifications include the optional modifications of tuning the steering wheel and tuning the driver's side knee bolster.

In some embodiments, the size, shape, and collapsing stiffness of the steering wheel can be varied to help protect the occupants. Also, in some embodiments, the driver's side knee bolster can be repositioned and the stiffness of the driver's side knee bolster can be tuned.

The passenger side knee bolster1108(seeFIGS. 11 and 12) can only be modified by stiffening knee bolster1108. This is because any reduction in stiffness of passenger side knee bolster1108would invalidate the results of second test606. Preferably, the process is designed so that no modification invalidates previous test results. Like other steps, the stage four modifications are preferably tuned until motor vehicle100passes fourth test614.

After motor vehicle100passes fourth test614, the process proceeds to fifth test618. Fifth test618determines whether motor vehicle100can protect a male occupant during a frontal 48 km/h collision when the male occupant is wearing his seat belt. Preferably, a hypothetical male occupant is tested in fifth test618and in some embodiments an AM50% crash test dummy (which stands for American Male, 50 percentile) is used to model the behavior of a hypothetical male occupant.

If motor vehicle100fails fifth test618, then the process moves to step620where stage five modifications can be made. Preferably, stage five modifications do not invalidate any of the test results from any of the previous tests. In one embodiment, stage five modifications include tuning the seat belt.

In some embodiments, the position, anchor points and/or tension of the seat belt can be adjusted to help protect the male occupant. Like other steps, the stage five modifications are preferably tuned until motor vehicle100passes fifth test618.

One of the goals of method600is to avoid making a modification or adjustment during a current test that would invalidate a previous successful test result. At this point in the preferred embodiment of method600, no other major modifications are available that would not invalidate previous test results and any modification could invalidate a previous successful test result. Therefore, there are no major modifications available for the remaining tests and the process attempts to confirm that motor vehicle100passes the next several tests.

After motor vehicle100passes fifth test618, the process proceeds to sixth test622, seventh test624and eighth test626. Sixth test622determines whether motor vehicle100can adequately protect a female occupant during a frontal 48 km/h collision when the female occupant is wearing her seat belt. Preferably, a hypothetical female occupant is tested in sixth test622and in some embodiments an AF5% crash test dummy (which stands for American Female 5 percentile) is used to model the behavior of a hypothetical female occupant.

Seventh test624determines whether motor vehicle100can protect a male occupant during a collision with an angled barrier at 40 km/h when the male occupant is not wearing his seat belt. Preferably, a hypothetical male occupant is tested in seventh test624and in some embodiments an AM50% crash test dummy (which stands for American Male, 50 percentile) is used to model the behavior of a hypothetical male occupant.

Eighth test626determines whether motor vehicle100can adequately protect a female occupant during a collision with an offset barrier at 40 km/h when the female occupant is wearing her seat belt. Preferably, a hypothetical female occupant is tested in eighth test626and in some embodiments an AF5% crash test dummy (which stands for American Female 5 percentile) is used to model the behavior of a hypothetical female occupant.

Again, because no major modifications are available, the process determines if motor vehicle100passes sixth test622, seventh test624and eighth test626. If motor vehicle100passes all of those tests, then the process proceeds to'step628where the process concludes that motor vehicle100is qualified to use new firing map300.

If motor vehicle100fails any one of the last three tests, then the process returns to a previous stage of modification. In some embodiments, this previous stage of modification can be determined by considering which modification would assist motor vehicle100in passing the failed test. Preferably, the highest stage of modification is selected with a goal of minimizing the number of tests that are invalidated. In other embodiments, this previous stage of modification is predetermined and the process moves to a certain predetermined modification stage if motor vehicle100fails any of the last three tests. In a preferred embodiment, the process moves to third test610if motor vehicle100fails any of the last three tests.

Although, it is preferred that the inflatable restraint include only two deployment modes, a first mode where the inflatable restraint does not deploy and a second mode where the inflatable restraint is deployed with a delay, it is possible to provide embodiments where a simultaneous deployment mode is used at some speed greater than 48 km/h. If a simultaneous deployment mode is used, it is preferred that the transition zone between the simultaneous deployment mode and any adjacent mote would not overlap with any regulation zone.

Using principles disclosed above, it is possible to provide a simplified inflatable restraint system that has more predictable characteristics, improved safety and the operation of which is easier to test and validate.

Each of the various components or features disclosed can be used alone or with other components or features. Each of the components or features can be considered discrete and independent building blocks. In some cases, combinations of the components or features can be considered a discrete unit.

While various embodiments of the invention have been described, it will be apparent to those of ordinary skill in the art that may more embodiments and implementations are possible that are within the scope of the invention. Accordingly, the invention is not to be restricted except in light of the attached claims and their equivalents.