SAE TECHNICAL
`PAPER SERIES
`
`921 596
`
`—
`
`A Review of the Potential for Vehicle On-Board
`
`Diagnostic Safety Systems
`
`Peter E. Bryant
`Automotive DeSugn and Engineering Consultant
`
`Reprinted from: Automobile Safety:
`Present and Future Technology
`(SP-925)
`
`The En Ineenn Socre
`.
`.
`.
`Q‘ EFor Adinginggwobmg
`"Land Sea Arrand Space,“
`INTERNATIONAL
`
`Future Transportation Technology
`Conference and Exposition
`Costa Mesa, California
`August10-13,1992
`
`— 4
`
`00 COMMONWEALTH DRIVE, WARRENDALE, PA 15096-0001 U.S.A.
`
`lPR2013-00417 - Ex. 1023
`
`Toyota Motor Corp., Petitioner
`1
`
`IPR2013-00417 - Ex. 1023
`Toyota Motor Corp., Petitioner
`1
`
`

`

`The appearance ot the tSSN code at the bottom ot this page indicates SAE's consent
`that copies ot the paper may be made tor personal or internal use 01 speCilic clients
`This consent is given or. the condition, however that the copier pay a SS 00 per article
`copy tee thtOugh the Copyright Clearance Center. Inc Operations Center 27
`Congress St r Salem, MA 01970 tor copying beyond that permitted by Sections 107
`Or 108 01 the U S Copyright Law This consent does not extend to other kinds ot
`copying such as copying lot general distribution.
`tor advertismg or promotional
`purposes tor creating new collective works, or tor resale
`
`SAE routinely stocxs printed papers tor a period 01 three years lollowing date 01
`publication Direct your orders to SAE Customer SENICE‘ Department
`
`To obtain Quantity reprint rates permiSSion to reprint a technical paper or permismon
`to use copyrighted SAE publications in other works, contact the SAE Publications
`Group
`
`Global
`Mobility
`[Database
`AII SAE papers standards. and selected
`poms are abstracted and indexed in the
`SAE Global Mobility Database
`
`No part we lhtS publication may by reproduced in any torm, in an electronic retrieval
`system or omen/Vise NI!hOUl the prior written permiSSion of the publisher
`
`ISSN 0148-7191
`
`Copyright 1992 Society of Automotive Engineers. Inc.
`
`posmons and opinions advanced in this paper are those of the authortst and not
`necessarily those at SAE The author is solely responSible tor the content 01 the
`paper A process is available by which discussmns Wlll be printed With the paper it
`.t is published in SAE transactions For permissnon to publish this paper in tull or in
`part contact the SAE Publications OiViSion
`
`Persons WtSmng to submit papers to be consrdered tor presentation or publication
`through SAE should send the manuscript or a 300 word abstract 01 a proposed
`manuscript to Secretary Engineering ActiVity Board. SAE
`
`Printed in USA
`
`2
`
`

`

`This material may be protected by Copyright law (Title 17 US. Code)
`
`921596
`
`A Review of the Potential for Vehicle On-Board
`Diagnostic Safety Systems
`
`Peter E. Bryant
`Automotive Desugn and Engineering Consultant
`
`ABSTRACT
`
`State and Federally mandated vehicle
`inspection programs have failed to prevent fatal
`aCCIdents due to worn parts or failed vehicle
`systems.
`Intelligent Vehicle/Highway Systems
`(IVHS) are being implemented and taking many
`forms » from traffic information systems to
`SOphisticated automated control of vehicles in
`
`motion. With IVHS. detecting unsafe vehicle
`components and systems in use becomes an
`important issue. This paper looks at On-Board
`Diagnostics (080) and examines how they may
`be applied. along with supplementary systems. to
`improve safety in automobiles. especially in an
`automated control enwroment
`
`LNIRQDLJCIIQN
`
`In 1988. the Department of Transportation
`(DOT). and National Highway Traffic Safety
`Administration (NHTSA). issued a report entitled
`"Study of The Effectiveness of State Motor Vehicle
`Inspection Programs". The reportbasically said
`"Periodic Motor Vehicle Inspection programs
`(PMVI), are not effective in reducing crashes
`because they fail to predict failures of systems and
`components". Their report confirmed others
`demonstrating that the inspection methods used
`by many states to prevent crashes due to
`
`component and system failure were virtually
`useless. Those same findings also implied that
`part 570 of the Code of Federal Regulations (CFR)
`Title 49 (Vehicles in-use Standards) was basically
`redundant. The reason given for the failure to
`prevent crashes was important news especially
`considering that the "Vehicle in-use" Standards
`were set up to prevent accidents due to
`component failure.
`
`Intelligent Vehicle and Highway Systems (IVHS) is
`emerging as the best direction to take in solving
`the highway congestion problems. There also
`exists the unsolved problem of reducing accidents
`due to component or system failure. Therefore. a
`method to prevent problems caused by
`mechanical and component failure needs to be
`identified prior to IVHS being implemented
`
`This paper examines the potential for use
`of an expanded On-Board Diagnostic (030)
`System. Both as a valid method to allow vehicles
`to safely interact with IVHS automatic controls,
`and to generally increase vehicle safety in the
`same way as originally intended in the CFR Title
`49 "Vehicle ln—use" Standards,
`
`97
`
`3
`
`

`

`QEQBAQKQBQUNQ
`
`Apart from a few mandated safety warning
`ligh.‘ systems. 080 systems have been mainly
`used to assist in diagnosis of emission controls. A
`light on the dash will come on and announce
`"Check Engine." The technician has to connect
`the OED computer output to an “off-board"
`computer to read possible areas of system or
`component failure displayed as "Trouble codes".
`These codes translate into corresponding
`component or system failure modes. The
`technician can then make the appropriate repairs.
`When failures occur that trigger the warning light
`to come on, they may also allow the system to go
`to a "limp home" mode to allow the vehicle to be
`driven. but at reduced performance level. Safety
`note: in a vehicle safety system if a control units
`fails. a "limp home" mode poses an interesting
`problem i.e.. A gross hydraulic failure that causes
`the brakes to become partially or totally ineffective
`may have no realistic acceptable "limp home"
`condition,
`
`For 080 to be an effective tool in accident
`
`prevention there are some important needs to
`address. For example; it will need to be expanded
`to diagnose condition of components and
`systems. It will need to interface with control
`systems that determine corrective action for the
`particular malfunction.
`It will need the ability to
`interact and communicate with both the operator
`and other parts of the various systems involved.
`including lVHS.
`
`There are many interesting long range
`benefits of 080 safety systems to be found.
`Especially in regard to used car sale or purchase:
`warranty monitoring; liability protection for the
`manufacturer; Insurance actuarial use and Bank
`
`re-financing vehicle suitability.
`
`ELLWEHLQLLSAETLSX S__E.M
`£2§2N§|DERAII_O_N_$
`
`0 Advanced Traffic Management Systems
`(ATMS)
`0 Advanced Driver lnformation Systems (ADIS)
`0 Freight and Fleet Control Operations
`0 Automated Vehicle Control Systems (AVCS)
`
`OBD safety systems will be required to
`interface with AVCS. One part of AVCS will
`provide the driver with useful information and
`warnings; using data collected by on-board
`sensors or transmitted from outside sources. 030
`will fit into this level of AVCS readily. At the most
`advanced level the AVCS may take over the
`driving tasks completely. on dedicated highway
`facilities. and in such locations as high demand
`urban corridors or intercity routes.
`
`Vital to the implementation of advanced
`IVHS. is the requirement for total elimination of
`vehicle failures due to components and/or safety
`related vehicle systems. If the use of expanded
`OBD technology can be effective in avoiding
`vehicle accrdents due to component or system
`failures for IVHS; it will also eliminate these
`causes of accidents in normal rural city/highway
`use.
`
`AQCIDENT PREVENTION POTENTIAL
`
`ENElBON—MEWQIQBS
`
`According to the Tri-level study on the
`causes of traffic accidents. conducted at Indiana
`
`University, Institute for Research in Public Safety
`(May 1979), environmental factors such as slick
`wet road surfaces contributed to nearly one half of
`all accidents in the USA. This is compounded by
`the degradation of components and systems due
`to normal wear or abuse,and the inability of the
`driver to gauge the impact on the performance of
`the various systems. The expanded 080 will
`indicate the condition of components and systems
`and thus. warn the driver of potentially dangerous
`situations compounded by environmental factors.
`
`IVHS technology is now generally viewed
`as the best direction to take to alleviate traffic
`
`HUMANEAQTQRfi
`
`problems. reduce accidents/pollution and cut
`economic losses due to highway delays and
`accidents. IVHS has been grouped into fOUr
`categories,
`
`The Tri-Ievel study also indicated that
`human factors were contributing and probable
`causes in 92.6% of accidents investigated in
`Phases 2 through 5 (1972-75) of their study,
`Implementation of IVHS measures will impact
`
`98
`
`4
`
`

`

`certain problems For example; it used to assist
`With service on antrlock brakes (ABS).
`
`The California Air Resources Board
`
`(CARB) has been working With the Society of
`Automotive Engineers (SAE) to standardize OBD
`systems for emissmns and diagnostic equipment
`used in testing
`
`080 WEAK LINKS
`
`Weak links in the emiSSion control 080 system
`
`1 CPU MEMORY PROBLEM
`
`in the past. in some vehicles. in order to turn off
`the "check engine“ indicator light on the dash
`followmg service, the microprocessor (CPU) that
`had detected a malfunction had to have its
`
`memory (RAM) purged in order to be reset. The
`reset method was accomplished by disconnecting
`the power source (battery) following service, The
`RAM then had no memory of the malfunction and
`can only learn of new ones. This gave people a
`way to erase the vital information that a
`malfunction had occmred and defeat the system
`The light was out but the fault still existed. This is
`not a desireable feature to have in a system that
`WI” rely on its memory to help predict failures and
`prevent accidents.
`'EE'Proms that are non-volatile
`are now in use. The ability to erase their stored
`failure data requires sophisticated equipment.
`Before this, the battery disconnect method could
`be used to permit a vehicle with certain types of
`failure modes to "pass” the emission test at smog
`check stations. The condition that caused the
`
`failure may not oc0ur again immediately, so it may
`not be disclosed during the test. Thus, allowing a
`defective car emission control system to pass the
`test.
`
`A safety system diagnosis will not allow
`this to happen if we are careful to put in
`safeguards against tampering. We will rely heavily
`on mileage monitoring in some instances to
`predict serVice intervals.
`lf it is possible to
`"Wipe-out" the memory that is recording mileage it
`would be disastrous.
`
`human factors in both positive and negative ways
`For example; How will naVigating systems
`contribute? Will accidents happen because
`drivers were distracted? Will accidents be avorded
`because drivers were alerted to weather or
`construction problems?
`
`If on‘board diagnostic safety Systems are
`an integral part of the Automated Vehicle Control
`Systems. they will have a definite role in reducmg
`accrdents due to human factors.
`In a system
`where human controls are suplemented With
`automated controls. the emphaSis WI" change the
`human role into more of an interactive one With
`
`the vehicle On-board diagnostics will Supply the
`inputs regarding use and maintenance of vehicle
`systems and accidents Will be prevented by
`system failure prediction 080 will put the driver
`on a communication level With the vehicle similiar
`
`to that of an aircraft pilot and his plane
`
`VEHICULAR.F.ACTORS
`
`Vehicular factors account for 7% of all
`injury acodents.
`It's been proven that Preventive
`Maintenance Vehicle Inspection (PMVI) programs
`have been ineffective in preventing vehicular
`failure acadents
`If we are to replace PMVI
`programs With anything . we have to acknowledge
`the reason that PMVI failed. The DOT PMVI
`
`study said "Existing inspection techniques do not
`provide inspectors with the ability to make
`meaningful predictions of when components may
`fail," This leads to the question of how 080
`safety systems 00uld be set-up and disciplined to
`avoid the same problem.
`
`To accompash this, 080 will need to be
`expanded into a control system as well as a
`diagnostic system. For this purpose the
`nomenclature of 080 will need to be modified to
`
`include references specifically to safety controlie.
`OBDSS (On-Board Diagnostic Safety System).
`
`QBLSIAIEQELHELRI
`
`The Federal Safety Standards call for
`some 030 functions to monitor certain safety
`related systems such as "Low Brake fluid" and
`"Fasten your seat belt". 080 is also in use as an
`aid to service technicians in trouble shooting
`
`99
`
`5
`
`

`

`2 QATALYIJCQQNVERIEB.PROBLEM
`
`Typically. catalytic converter condition
`monitoring has been out of the emission
`diagnostic closed-loop control system. This is a
`bad situation because the converter can be fatally
`
`damaged by failure of a closedloop control
`element and not be detected as failed. However
`the new CARB OBD rules regarding converter
`Overtemp detection will help to protect converters
`and reduce failures in future cars.
`
`All kinds of 080 system weak links WI”
`Surface as development occurs They must all be
`elliminated in 080 safety systems
`
`SAF ETY OBD FEASIBILITY
`
`The state of the art indicates that the
`
`technology and hardware exists for deSigning and
`burlding on-board diagnostic safety systems in
`automobiles
`In fact. many manufacturers now
`offer "smart car' options that can perform safety
`related functions that
`
`0 Control lights
`0 Monitor tire pressures
`o Prevent wheel lock-up under braking
`(ABS)
`0 Detect potential collision Situations
`0 Control wheel traction on slick roads
`
`0 Reduce night viSicn problems
`0 Monitor engine problems
`0 Monitor driver function
`
`Microprocessor based sensors and microcomputer
`control is now used for monitoring and controlling
`functions of devices and mechanisms from simple
`digital temperature gauges to complicated space
`shuttle systems
`
`Today. sensors are available that can
`detect changes and properties of condition. speed.
`temperature. distance. viscosity. color, dimension.
`composition and vibration. to name just a few
`Sensors for an OBDSS are on the shelf now
`
`CONTROL. _$..Y..S.TE,M DESIGN
`CQNSJQERATIQNS
`
`Backup systems.
`
`Some systems will need extensive
`modification to work well enough to av0id
`
`catastrophic failure problems. Consider the
`braking system as an example:
`
`A seldom encountered. but feasible.
`
`In
`
`failure mode is a gross loss of hydraulic fluid.
`this event even the mandated federal safety
`standard "split" hydraulic system would be useless
`in certain lVHS situations. At speed. the manual
`park brake does not help much when the front
`brakes have failed completely. Braking distances
`increase dramatically. Without some kind of
`effective alternative or back-up system. the only
`function that the 080 can serve is to announce
`
`the failure This will not be acceptable if it is to
`prevent an accident.
`
`In an AVCS enviroment. If a vehicle is
`equipped to detect a failure mode Such as
`hydraulic fluid loss. it must be able to pr0vide a
`controlled alternative method of stopping to
`prevent an accident,
`
`Alternative vehicle braking methods
`already exist. These include driveline devices such
`as electric retarders. Retarders are in common
`
`use in buses and trains. Many transit authorities
`specrfy their installation in their bid documents
`because they also prolong brake service life.
`Electric brakes have been used for years on horse
`and boat trailers and are very effective. Some
`heavy duty vehicles have hydraulic retarders
`designed into the torque converter system of the
`automatic transmission.
`
`The point is. there are back-up systems
`being used in vehicles right now. They could
`easily be integrated into passenger cars and other
`vehicles. Devices. such as electric retarders could
`be integrated into the normal braking system and
`even enhance the total braking system
`performance just like a booster unit does. Thus.
`becoming an active participant in safety as well as
`a standby alternative to the primary system. The
`downside of using such backup systems is the
`added cost. Historically. safety has not been a big
`incentive to car buyers.
`
`The objective of "predicting" system or
`component failure can be achieved with expanded
`OBD.
`It is a fairly easy technological exercise to
`use sensors to detect brake pad wear. tire tread
`depth. tire temperature, inflation. or even steering
`system wear.
`It is also reasonably easy to supply
`that data to the driver and predict service
`
`100
`
`6
`
`

`

`requirements using illuminated displays. i.e.. "tire
`rotation due in 1,000 miles" or. "LF tire will need
`replacement in 5.000 miles". or " Check LF tire
`condition." Apart from the question of the cost of
`these systems and the readiness of the public to
`accept them. There is the problem is in deciding
`which action to program the system to take in the
`event that the failure warning is ignored, This
`question Will be addressed later under the heading
`"System Controls"
`
`IARQEIWG OBD SAFEIYSYSIEMS
`
`The Tri-State Studies revealed the followmg
`accident/injury data.
`
`0 Human factors contributed to 92 6% of all
`accrdents
`
`o 33% of these involved environmental factors
`were.
`
`. View obstructions 12%
`- Slick/wet roads 10%
`
`o 7% of all accidents were directly due to
`vehicular factors
`
`0 Leading vehicular system or part failure
`factors were
`- Gross brake failure. 3%
`- Inadequate tire tread depth. 3%
`. Improper side to side brake
`imbalance 2%
`. Under inflation of tires. 1%
`- Vehicle related Vision obstructions
`contributed to 1%
`The rest were
`
`~ Excessive steering free play.
`less than 1%
`
`- lnoperable lights and signals,
`less than 1%
`
`- Door came open - pre-crash.
`less than 1%
`
`Simple analysis of this data reveals that there are
`basically three critical systems to monitor for
`OBDSS;
`
`1) gralg§ystem condition diagnosis and control:
`
`2) flrtheel condition diagnosis and control;
`
`3) SteerjflQLS.u§D.eLr1$.i.Qn condition diagnosis and
`control.
`
`DIAGNQSLiBEQULRED
`
`1, Brake systems will require diagnosis to
`determine condition of the following :
`1) Brake pads or shoes. Discs or drums.
`2) Hydraulic system.
`3) A88 electronics.
`
`2. Tire/wheel elements for diagnosis include:
`1) inflation status.
`2) Tread wear.
`3) Wheel tightness.
`
`3 Steering/suspension elements for diagnosis
`include.
`
`1) Free play at wheel.
`2) Power system function
`3) Excessive wheel occilations (Worn out
`shock absorbers. dampers or imbalanced wheels).
`
`It appears that by diagnosing three
`Note;
`elements of each system, we could get enough
`data to make worthwhile control decisions
`
`In addition the diagnosis control has to
`possible,
`be checked or check itself. (To ensure that it is
`also functioning correctly)
`
`SYSIEMQQMMUNJQAILQN
`
`In the "smart car' of the future, many of
`the systems will communicate with the driver by
`“voice." The driver may also communicate with
`the vehicle by "voice." The technology to do this
`has been developed and computers that operate
`entirely by voice control are available, Thus. there
`is no reason that the OBD system cannot also use
`voice communication._ The voice communication
`could be complemented with an electronic display
`for the three safety systems
`
`SYSIEMQQEIRQLSI
`
`For major system failures. control
`functions are fairly easy to de5ign, i e ,
`if the
`hydraulic brakes have totally failed and theback up
`system is needed. the control module will bring it
`on line. Other control functions may not be so
`easy to implement. Especially those involved with
`predicting failures and indicating that costly
`service needs to be done. if expanded OBD is to
`be effective in replacing PMVI and prevent
`
`101
`
`7
`
`

`

`It must have the capability to meant
`accidents.
`failure modes from developing .
`The only way it can do this is by diagnosis
`and some form of preventative action. At the
`present time and in the past, these functions have
`been outlined in owners manuals and service
`books as "recommended maintenance and
`service." It the owner did not follow the
`recommendations. the vehicle fell into
`substandard conditions. Quite often the owners
`
`ignored the service recommendations because
`they knew that they would trade-in the car for a
`new one after a year or two anyway. so why
`bother?
`
`The answer to this problem may also lie in
`the adoption of expanded OBD!
`If the car can
`now communicate with the driver. as we have
`
`suggested. then the communication dialogue
`could also be expanded to include the information
`from the owners manual regarding service This
`way the car could "ask" to be serviced as a
`preventive maintenance measure. Let us go one
`step further and examine the ultimate control and
`liability responsibility
`
`BQTIQMLINLQULSI mu
`
`0. Should a "smart car“ be able to shut
`
`itself down if it predicts a dangerous
`failure mode situation?
`
`A. No! The reason is not one of safety,
`but liability. The car may be needed in
`order to prevent a worst case scenario
`than that already predicted.
`
`For example; let's assume that a car has two very
`bad front tires that should be changed for safe
`operation of the vehicle. Let's also assume that
`the owner is broke, out of work and can't afford
`the repairs, and suddenly his/her spouse has a life
`threatening emergency in the middle of the night
`and needs to be taken to a hospital
`
`0. Would the vehicle manufacturer be
`liable if the unsafe vehicle could not be
`used to try and save the spouses life?
`
`A. Probably yes; because the question of
`priorities would call for a legal resolution to
`the problem.
`
`Now the question arises; how can the diagnosed
`problem be handled and the vehicle manufacturer
`avoid being liable if the operator ignores the
`03088 warning? If the system can't overide the
`operator. then how is this situation to be avoided?
`
`The best answer may be found in the
`vehicle's communication capability. For example;
`assume that the bad tires didn't happen over night.
`but are the result of normal wear and tear. As
`
`they degraded. the car informed the driver about
`the problem again and added a caveat.
`
`Hypotheticaldm
`
`Dave goes to his car. identifies himself then opens
`the now unlocked door. (The car recognised his
`voice and unlocked the door.) He gets in and tells
`the car to start the engine.
`
`Car:
`
`"Hello Dave; the safety systems all check out
`except for the tires. The left front tire has 2,500
`miles of useable life and the right front is within
`1,000 miles. As you know Dave. this is your
`second warning. I have been programmed to limit
`the speed of this car to 15 miles per hour if you go
`inside the 500 miles wear range limit.
`l must also
`broadcast the "Need Service" code. Dave. I have
`checked with the Network and obtained the latest
`
`tire prices. May I remind you that you will recieve
`remittance points from your Insurance carrier for
`prompt attention to service announcements. Shall
`I make an appointment for you. Dave"?
`
`If the driver makes a negative response
`the computer could then (at the 500 miles left
`point) start broadcasting a code and limit the
`speed of the car to 15 mph. This code could
`inform his insurance carrier and the DMV of the
`
`safety related tire problem. The code would also
`be available for scrutiny by any any other
`interested party. Of course. this was not the first
`warning to Dave of the problem and the computer
`would have the ability to inform other interested
`parties including other passengers in the car.
`It is
`also possible that the computer could warn other
`motorists via their control computer. It would be
`fairly obvious to anyone that there was a problem
`with the car only doing 15 mph.
`
`But. this speed would not pose a serious
`problem in getting his spouse to the hospital
`should the need arise. and it would be difficult to
`
`102
`
`8
`
`

`

`show the manufacturer liable in this situation. The
`owner chose to buy a car with 08088 so he could
`use the AVCS highway. He read the warranty and
`the OBDSS statements and agreed to the
`conditions.
`
`Note: For IVHS use the automated highway could
`be alerted of a potentially defective car and it
`could be "turned away" at the controlled access
`entry ramp automatically.
`
`There are, of course. alternative
`disciplines that may be less militant and easier to
`use. For example: It would be fairly easy to put a
`command into the control system that makes the
`situation intolerable for the driver. but reduces the
`accident potential. This could be as simple as an
`annoying tone or noise, but it still allows the car to
`run at reduced speed.
`
`This way. the vehicle could still be used in
`an emergency but couldn't be driven too fast to
`control in the case of a flat tire or blowout.
`Whatever is done to alert drivers of problems with
`vehicle 080 systems will not be effective unless it
`carries the weight of preventative action. Cars
`with potentially dangerous parts or systems would
`be extremely dangerous in IVHS freeway lanes
`that were set up for "platooning". ie: cars in groups
`of say five cars, running at 5 feet apart at 60 mph.
`(Platooning is being experimented with today in
`California.)
`
`RQTENTIAL SIDE EFFECT BENEFITS:
`
`The side effects of having safety
`controlled systems in vehicles that can track and
`diagnose problems could be beneficial in several
`ways.
`
`For example: Used cars will carry their
`service history with them! By just turning the
`ignition key to the stand-by position, a potential
`buyer will be able to determine it's condition. The
`computer will tell them how the brakes. tires and
`steering are.
`If we hook the engine diagnosis into
`it, the engine computer will also know when the oil
`was last changed and how the car is running. The
`car will virtually sell itself. and the buyer will know
`it isn't lying.
`
`Phasing in automated highway use will be
`easier, because the car could tell the highway
`controller if it was not suitable for automatic
`operation.
`
`Police could carry a signaler that could put
`the car into the "limp home" mode or even stop it if
`they were chasing it.
`
`People who are not technically inclined
`would not have to try and understand what is
`wrong with the car.
`it wiil tell them what to do.
`
`OBDSS will work very well within the development
`of "the smart car" and may increase sales appeal.
`
`ACCIDENT
`FACTOR
`
`Vehicular
`
`. Environmental
`
`Improper
`Driving
`
`TOTALS
`
`ACCIDENT REDUCTION PRQJECTIQNS
`
`CURRENT
`%AGE
`OF TOTAL
`ACCIDENTS
`
`ESTIMATED
`PROJECTED
`%AGE
`REDUCTION
`
`PROJECTED
`% OF TOTAL
`ACCIDENTS
`AFTER REDUCTION
`
`7%
`
`16%
`
`66529
`
`
`83%
`
`60%
`
`15%
`
`1Q°Zq
`
`Not
`
`4.2%
`
`2.4%
`
`15%
`
`Am: M
`
`103
`
`9
`
`

`

`EBQJECILBEDLLClllQNfiJ N. .696. ! DENT. S
`
`U SLN QDAIA ERQM1988_S_T_A.TJSILQS
`(DATA BASE SOURCES. FOLLOW)
`
`In order to make a comparison between
`data pre-OBDSS. and post-OBDSS we made the
`following assumptions for post-OBDSS‘
`
`A) Total of vehicle accidents
`100% = 20.600000
`B) Drivers (vehicles) involved
`= 36200000
`
`191:! protected reduction Delgemwe = 13.2%
`
`0 That OBDSS adoption becomes part of
`IVHS plans.
`
`For
`
`0 That the post—OBDSS fleet is 100%
`
`0 That OBDSS includes certain smart car
`
`sensors and controls that are logical
`developments to use in IVHS and OBDSS
`equipped cars. These would include such
`items as rain detectors and noxious gas
`detectors (to detect carbon monoxide)
`which would help in reducing accidents
`due to human factors and drivers errors
`
`caused by these elements. Also, included
`are developments necessary for inclUSion
`of vehicles in IVHS future plans. I e.
`collision avoidance radar.
`
`0 That accident/crashes due to vehicle
`
`factors are reduced by at least 60% due to
`the OBDSS capability in keeping defiCient
`components and systems off the roads,
`
`0 That accidents/crashes caused by
`environmental factors are reduced by a
`conservative estimate of 15%. credited to
`a partial reduction in 10% of the cause
`(ie. slick roads). due to smart car options
`and improved performance, Also credited
`to a further reduction obtained from
`removal of interaction with vehicle factors
`
`such as tire tread depth.
`
`0 That accidents due to improper driving
`(human error) currently accredited with
`being the reason for approximately 66% of
`all crashes and accidents. Are reduced by
`a target 10% (This target reduction is
`justified by the adoption of smart car
`options such as collision avoidance and
`ABS, and their subsequent impact on the
`data.)
`
`A) projected total vehicle accidents =
`17.880800
`
`8) projected total vehicle accident
`reduction = 2.719.200
`
`N916: Because we have reduced the total number
`of accident causes and accidents that were
`
`projected to happen. We could also expect that
`the projected number of total (driver) vehicles
`involved to be reduced. To arrive at this projection
`we looked at the ratio of vehicle accidents to
`drivers involved for 1988 and used the same ratio
`
`for drivers (vehicles) projected reduction.
`
`This exercise shows that the total drivers
`
`(vehicles) involved (8) would be approximately
`31421600, A reduction 014,778,400
`drivers/vehicles (13.2%). According to the
`database the cost of motor vehicle accidents in
`
`If we had reduced this by
`1988 was $70.2 billion.
`13.2% it would show a cost savings of 592664
`billion. For cost/benifit comparison purposes. it is
`estimated that an increase in the federal gasoline
`tax of one cent will increase the federal revenue
`
`by one billion dollars.
`
`Qde us_io.n_s
`
`The review indicates that the technology
`exists to design. manufacture and install
`saletyrelated on-board diagnostic safety control
`systems. With funding already being made
`available for IVHS. and with the need for a safety
`control system of some sort to make some
`portions of the AVCS part of IVHS systems
`feasible.
`It is not unreasonable to assume that a
`
`federally mandated safety program will force
`safety control systems to be included on vehicles
`interfacing with AVCS. Some vehicle
`
`104
`
`10
`
`10
`
`

`

`manufacturers are already into their own safety
`system development programs,
`
`The ability of a vehicle to specify or even
`demand service of it's owner/driver. in order to be
`used in AVCS lanes on the highway. makes
`owning such a vehicle a vastly different situation
`than we currently experience now, Add to that.
`the cars ability to report the owner to the
`insurance carrier or even the various authorities.
`
`and a very interesting situation arises. The very
`thought of that. may be enough to turn people
`away from 08088
`
`The potential of 08088 to save lives will
`have to be weighed against the cost of
`implementation and the feasibility of such a
`program. before it becomes a reality. The purpose
`of this revrew is to help start the dialogue
`
`REFERENCES
`
`institute for Highway Safety (HHS) publication.
`1
`HHS Fact 1989
`
`2. Office of Crash Avoidance Research (NHTSA),
`Intelligent Vehicle Highway System (IVHS)
`accident analysis 1984-1986 cardfile database
`on pre-crash factor (3 to 5 seconds prior to crash)
`
`3. Tri-level Study of The Causes of Traffic
`Accidents. J R. Treat et al, May 79, Institute for
`Research to Public Safety Indian Unwersxty.
`(DOT contract HS-O34-3-535.)
`
`4 Accident Facts, 1989 Edition Nation Traffic
`C0unCil
`
`105
`
`11
`
`11
`
`