The most difficult at-fault fatal crashes to avoid with current active safety technology

Objective We studied which current fatal at-fault crashes would occur despite the most advanced current active safety devices (up to SAE level 2 of driving automation) and how frequent these crashes would be. Methods We carried out a cross-sectional study of passenger cars that were first registered during the period 1st January 2010 to 31st December 2017 in Finland. To gain the true exposure for these cars, we accessed the national Vehicular and Driver Data Register to obtain the mileage information and the registration count for the study period of 2010-17. Similarly, we accessed the registry of Finnish road accident investigation teams and included all fatal at-fault crashes among the cars in our study for the same period. We used a real world reference technology for each active safety system in our analysis and chose one car brand as an example. This gave us exact system specifications and enabled testing the operation of the systems on the road. We performed field tests to gain further information on the precise operation of the safety systems in different operating conditions. Finally, we gathered all information on the studied active safety systems and analyzed the investigated at-fault fatal crashes case-by-case using our four level method. Results Cars in our study were the primary party in 113 investigated fatal accidents during the years 2010-17. In 87 of the accidents, the leading cause of death was the injuries due to the crash, and these cases were classified as “unavoidable” (n = 58, 67 %), “avoidable” (n = 26, 30 %) or unsolved (n = 3, 3 %). Of the 58 “unavoidable” crashes 21 (36 %) were suicides, 21 (36%) involved active driver input which would have prevented the safety system operation, 15 (17 %) featured circumstances beyond the safety system performance and in one loss-of-control crash the driver had disabled the relevant safety system (electronic stability control). The registration years of the cars in our study (2010-17) totaled 3,772,864 and during this period, the cars travelled 75.9 billion kilometers. The crash incidence of the “unavoidable” at-fault fatal crashes was 0.76-0.80 fatal crashes per billion kilometers and 15-16 fatal crashes per million registration years. Conclusions We calculated a crash incidence for the “unavoidable” crashes which was 20–27% smaller than the observed crash rate of ESC-fitted passenger cars in our previous study. We concluded that suicides, active driver input until the crash, and challenging weather and road conditions are the most difficult factors for current active safety systems. Our analysis did not account for issues such as system usability or driver acceptance and therefore our results should be regarded as something that is currently theoretically achievable. However, the observed incidence is a good reference for automated driving development and the crash rate of automated cars.Peer reviewe

Which not-at-fault crashes are unavoidable by using current active safety technology?

Previous research has focused on analysing crash reduction potential of active safety technology in at-fault passenger cars, but only a few studies have examined counterparties' possibilities to avoid collisions by using advanced driver assistance systems (ADAS). This study quantified the incidence of fatal not-at-fault passenger car crashes that current ADAS (up to SAE level 2) would be unable to avoid. We used data taken from in-depth investigated fatal crashes in which a passenger car was involved, that car having been first registered during the period 1 January 2010 to 31 December 2017 in Finland. The evaluation of unavoidable crashes consisted of two evaluation rounds. The preliminary evaluation round identified potential active safety systems that could have operated in the studied cases. In the following round, we made a five-level case-by-case analysis including a time headway analysis in order to evaluate the possibilities for crash avoidance. The crash data included 63 fatal crashes, of which five were excluded because the death was due to a sudden illness attack. The remaining 58 crashes were classified as follows: probably unavoidable (n = 51), avoidable (n = 3), and unclear (n = 4). The crash incidence of the unavoidable not-at-fault party crashes was 0.67–0.73 fatal crashes per billion kilometers and 14–15 fatal crashes per million registration years. The results indicate that current active safety systems may be able to prevent not-at-fault party fatal crashes only in a few cases and that the driver's role in road safety remains important despite the deployment of the active safety systems.publishedVersionPeer reviewe

Äärimmäisen taloudellisen kulkuneuvon suunnittelu

The aim of this Thesis was to design a mileage marathon vehicle for Finnish competition called 'Pisaralla Pisimmälle'. The first chapters of the thesis involve the basic theory concerning energy flow in a vehicle and vehicle efficiency. Some simulation and measurement methods are also introduced to study the efficiency of the vehicle. The implementation of the theory is briefly introduced in Chapter 4. The design and implementation covers all subsystems of the vehicle: frame, shell, steering and suspension, engine selection and modifications, power train and electronics. The vehicle efficiency and performance is measured in several different ways and the results cover detailed information about the overall efficiency of the vehicle, aerodynamic characteristics, rolling resistance characteristics and overall performance. In the end of the Thesis is discussed some of the success factors of the mileage marathon racing and some notifications concerning the project itself.Työn tarkoituksena oli suunnitella taloudellisuuskilpa-ajoneuvo Suomessa järjestettävään Pisaralla Pisimmälle -kilpailuun. Työn alkuosassa käydään läpi ajoneuvon läpi kulkevaan energiavirtaan liittyvää perusteoriaa ja tarkastellaan ajoneuvon kokonaishyötysuhteeseen ja ajovastuksiin liittyviä seikkoja. Alussa esitellään myös muutamia simulointi- ja mittausmenettelyjä, joiden avulla voidaan tutkia ja varmentaa ajoneuvon hyötysuhteeseen ja ajovastuksiin liittyviä tunnuslukuja. Neljännessä luvussa esitellään ajoneuvon suunnittelu ja rakentaminen pintapuolisesti. Käsittely kattaa kaikki osajärjestelmät: rungon, korin, pyörätuennan ja ohjauksen, moottorin, voimansiirron ja sähköjärjestelmän. Työssä perehdyttiin ajoneuvon kokonaishyötysuhteeseen ja ajovastuksiin monin eri keinoin. Saadut tulokset käsittävät yksityiskohtaista tietoa ajoneuvon kokonaishyötysuhteesta ja sen eri tekijöistä, vierintävastuksesta, ilmanvastuksesta ja suorituskyvystä. Työn loppuosassa poimitaan esiin lajiin liittyvät keskeiset seikat ja pohditaan hieman koko projektiin liittyviä asioita

Kuinka autot suojaavat kuljettajiaan ja pitäisikö autoja suojata kuljettajiltaan: turvatyynyistä ajamisen automaatioon

This thesis examined not only the effectiveness of the currently available safety devices for passenger cars (introduced by 2018) but also crashes that cannot be prevented by current safety technology. The research was carried out as a statistical analysis using Finnish databases as material. The material of the Finnish Crash Data Institute (OTI) was used exclusively as the crash data. In the publications, this crash data was combined with appropriate Finnish databases as needed. All four publications were quantitative observational studies. The first three studies were retrospective cross-sectional studies regarding passenger car safety technology, but the first one also included a case-control part. The last of these studies was a prospective cohort study, where the follow-up period for those with attention deficit-hyperactivity disorder (ADHD) had been going on for a considerable period of 40 years. The results of the studies were presented as odds ratios (OR) for the case-control and cohort studies, and as the prevalence for the cross-sectional studies. According to the results, the airbags contributed little to eye injuries (the prevalence of possible eye injuries was fewer than 4 injuries per 10,000 injured), but the non-use of the seat belt increased the odds of both head injuries (OR 2.50, 95% confidence interval [1.59; 3.97]) and death (OR 5.89 [3.33;10.9]). In addition, the injury (-29% [-27%;-31%]) and fatal (-58% [-45%; -69%]) crash rates were significantly lower for passenger cars having electronic stability control (ESC) than for older, non-ESC cars. If the ESC cars mentioned above are compared to newer cars having almost all available active safety devices, the analysis showed that the incidence of at-fault fatal crashes could be reduced by another 20-27% per kilometre, i.e. down to 0.48-0.53 crashes per billion kilometres when sudden disease attacks and suicides were not taken into account. Crashes that are most difficult to prevent using current safety technology are suicides, crashes caused by active but erroneous driver control, and crashes occurring in bad weather or road conditions. In addition to the above, shortcomings in usability, consumer resistance, and behavioural adaptation may be risks in the future. However, the results of this dissertation showed that currently, the most significant negative behaviour regarding safety devices was the non-use of safety devices. Non-medicated ADHD is an example of a single factor leading to highly complex cause-and-effect relationships regarding risk-taking. In the results, ADHD combined not only with increased mortality but also with elevated criminality (OR 24.3 [3.21; 184]) and drunk driving (OR 5.61 [2.30; 13.6]). The purpose of the example was not to stigmatize people with ADHD but to show how a disease with perinatal exposure factors can lead to crashes that are difficult to prevent.Työssä tutkittiin markkinoilla olevien (vuoteen 2018 mennessä esiteltyjen) henkilöauton turvalaitteiden tehokkuutta ja toisaalta onnettomuuksia, joita ei pystytä nykyisillä turvalaitteilla estämään. Tutkimus toteutettiin tilastollisena analyysinä, jonka aineistona käytettiin suomalaisia tietokantoja. Onnettomuusaineistona käytettiin Onnettomuustietoinstituutin hallinnoimia tietokantoja, joita yhdistettiin osatutkimuksissa tarpeen mukaan soveltuviin aineistoihin. Kaikki tutkimukset olivat luonteeltaan havainnoivia ja määrällisiä. Kolme ensimmäistä osatutkimusta oli retrospektiivisiä turvatekniikkaa koskevia poikittaistutkimuksia, mutta ensimmäisessä osatutkimuksessa oli myös tapaus-verrokki-osa. Viimeinen tutkimuksista oli prospektiivinen kohorttitutkimus, jossa aktiivisuuden ja tarkkaavuuden häiriön (ADHD) omaavien seurantajakso oli jatkunut jo 40 vuotta. Tutkimusten tuloksiin on otosten osalta laskettu oleelliset ristitulosuhteet (odds ratio, OR) ja poikittaistutkimuksissa oleelliset vallitsevuudet. Tulosten mukaan turvatyynyt eivät juuri aiheuttaneet silmävammoja (mahdollisten silmävammojen vallitsevuus alle 4 vammaa/10 000 vammautunutta), mutta turvavyön käyttämättömyys nosti sekä päävammojen (OR 2,50, 95 % luottamusväli [1,59; 3,97]) että kuoleman (OR 5,89 [3,33;10,9]) mahdollisuutta merkitsevästi. Lisäksi ajonvakautuksella varustetuille henkilöautoille sattui merkittävästi vähemmän sekä vammautumiseen (-29 % [-27 %;-31 %]) että kuolemaan (-58 % [-45 %; -69%]) johtaneita onnettomuuksia kuin vanhemmille, ilman ajonvakautusta olleille henkilöautoille. Kun edellä mainittua ajonvakautusautoa verrataan uudempaan, miltei kaikilla saatavilla olevilla aktiivisilla turvalaitteilla varustettuun autoon, aiheutettujen kuolemaan johtaneiden onnettomuuksien voidaan arvioida laskevan vielä 20-27 % kilometriä kohden, aina 0,48-0,53 onnettomuutta per miljardi kilometriä asti, kun sairaskohtauksia ja itsemurhia ei huomioida. Nykyisen turvatekniikan kannalta vaikeimmin estettäviä onnettomuuksia ovat itsemurhat, kuljettajan virheellisen hallintaliikkeen takia ja huonojen sää- tai keliolojen vallitessa sattuneet onnettomuudet. Edellisten lisäksi muun muassa puutteet käytettävyydessä, kuluttajien vastustus ja turvalaitteiden hyödyn ulosmittaaminen saattavat olla riskejä tulevaisuudessa, mutta tämän työn tuloksissa merkittävin kielteinen käyttäytymismalli oli turvalaitteiden käyttämättömyys. Lääkitsemätön ADHD on esimerkki yhdestä riskitekijästä, johon liittyy erittäin monimutkaisia syy-seuraus-suhteita. Tuloksissa ADHD esiintyi yhdessä kohonneen kuolleisuuden, rikollisuuden (OR 24,3 [3,21; 184]) ja liikennejuopumusriskin (OR 5.61 [2.30; 13.6]) kanssa. Esimerkin tarkoituksena ei ollut leimata ADHD:a sairastavia, vaan osoittaa, miten synnynnäisiä altistustekijöitä omaava sairaus voi johtaa onnettomuuksiin, joita on vaikea estää

The most difficult at-fault fatal crashes to avoid with current active safety technology

Objective: We studied which current fatal at-fault crashes would occur despite the most advanced current active safety devices (up to SAE level 2 of driving automation) and how frequent these crashes would be. Methods: We carried out a cross-sectional study of passenger cars that were first registered during the period 1st January 2010 to 31st December 2017 in Finland. To gain the true exposure for these cars, we accessed the national Vehicular and Driver Data Register to obtain the mileage information and the registration count for the study period of 2010-17. Similarly, we accessed the registry of Finnish road accident investigation teams and included all fatal at-fault crashes among the cars in our study for the same period. We used a real world reference technology for each active safety system in our analysis and chose one car brand as an example. This gave us exact system specifications and enabled testing the operation of the systems on the road. We performed field tests to gain further information on the precise operation of the safety systems in different operating conditions. Finally, we gathered all information on the studied active safety systems and analyzed the investigated at-fault fatal crashes case-by-case using our four level method. Results: Cars in our study were the primary party in 113 investigated fatal accidents during the years 2010-17. In 87 of the accidents, the leading cause of death was the injuries due to the crash, and these cases were classified as “unavoidable” (n = 58, 67 %), “avoidable” (n = 26, 30 %) or unsolved (n = 3, 3 %). Of the 58 “unavoidable” crashes 21 (36 %) were suicides, 21 (36%) involved active driver input which would have prevented the safety system operation, 15 (17 %) featured circumstances beyond the safety system performance and in one loss-of-control crash the driver had disabled the relevant safety system (electronic stability control). The registration years of the cars in our study (2010-17) totaled 3,772,864 and during this period, the cars travelled 75.9billion kilometers. The crash incidence of the “unavoidable” at-fault fatal crashes was 0.76-0.80 fatal crashes per billion kilometers and 15-16 fatal crashes per million registration years. Conclusions: We calculated a crash incidence for the “unavoidable” crashes which was 20–27% smaller than the observed crash rate of ESC-fitted passenger cars in our previous study. We concluded that suicides, active driver input until the crash, and challenging weather and road conditions are the most difficult factors for current active safety systems. Our analysis did not account for issues such as system usability or driver acceptance and therefore our results should be regarded as something that is currently theoretically achievable. However, the observed incidence is a good reference for automated driving development and the crash rate of automated cars.Peer reviewe