The use of antilock braking systems (ABS) on heavy trucks and trailers. An interview investigation. Revision 1. 1988-03-28

VTlnatat

No:

TF 50-11

_{Date: 1988-06-27}

Title:

_{THE USE OF ANTILOCK BRAKING SYSTEMS (ABS) ON HEAVY}

TRUCKS AND TRAILERS. AN INTERVIEW INVESTIGATION.

REVISION 1. 1988-03-28

Author:

_{Olle Nordström}

Division:

TF

Project no:

50 328-4

Project title:

_{Interview investigation concerning in service experience with}

'

_ABS-brakes

Sponsor:

_{UMTRI, Michigan USA}

Distribution:

fféé / restricted /

Statens väg- och trafikinstitut

V'00/7 ha'

Pa: 581 01 Linköping. Tel. 013-204000. Telex50125 VTISGIS. Telefax013-14 1436

' Besök: Olaus Ma nus väg BZ Linköping

THE USE OF ANTILOCK BRHKING SYSTEMS (ABS) ON HEAUY TRUCKS AND TRAILERS.AN INTERUIEN INUESTIGRTION.

Revision 1 1988.03.28 Olle Nordström

Swedish Road and Traffic Research Institute S*5810l Linköping

INTRODUCTION __-_.I-___-_

The information concerning ABS reported here has been gathered by means of telephone interviews with technical managers and owners of trucking companies in Sweden and Norway selected at random From lists delivered by the Swedish truck manufacturer Uolvo and the ABS* dealers NABCO,Hova ,FOMH,Ãngelholm and the Norwegian vehicle accessory dealer MoRek A/S ,Oslo .

Gathering of information concerning the

reliability,maintain-ability,trucking environment and performance of ABS equipped

heavy trucks and trailers from two or more fleets including one that uses Bosch ABS.

METHOD

1 ) Gathering names of trucking companies with

ABS-equipped vehicles from truck manufacturers and ABS-dealers 2) Sending questionnaires to selected trucking companies 3)Telephone interviews with technical representatives

of these companies. RESULTS

0 TRUCKING COMPANIES

Kinnarps AB,Falköping Sweden

Termotransport AB Kristianstad Sweden Najortrans ñ/S Oslo Norway

Troms Innland Rutehil, Finnsnes ,Norway Tor Fossberg Transport,Rasta, Norway

? 7 1 0 0 3 3 3 3 1 1 UEHICLE FLEETS

COMPANY e : Kinnarps HB,Falköping,Sweden Uehicle fleet:

l two axle Volvo F10 tractor MABCO 2 two axle Uolvo F10 tractor NABCO 5 two axle Uolvo F10 tractor 09800 5 two axle Uolvo F10 tractor NABCO l two axla Scania tractor NHBCO

channel ABS 1983 240 000 km channel ABS ?984 180 000 km channel ABS 1985 120 000 km channel ABS 1987 20 000 km channel ABS 198? 20 000 k -b . b . b . b . b

PJ mml hmm m UO HL ma ms wv.xum m Ex ®®®®. mam mawzn mg 888 sm

33m IO KM ma o :Ec cm> n %Uo m Ada Ly HM mH mL 3. mc Do w mco mcc m .mm Bw w mm nwm m" UO HL ma ms nw. :U mm Ex sa a GN mm mm üas "L Owum cc ou Lm HH ML w mm m om Hh mg 88 mm m 33 m "m mm Mm cc mzo w OQ mQ B" mxus t »ma n cm > ss mm mm m Ma xms UM wa F3 mm Lo zho am 0. m\ c wcm eL oh m: n G >zc uzoo Ex Gsm m nam så ass smm ma mm aws hm x saa mm

33m mmL xm ma co :E cm» ytan Ham L» HM mH mL 3. mc 00 v u CML HmE mmç L» man sm s Ga .Ex :i ass mm. :i 888 Gmm Ex sas S®m u mm mm HH z.m x Gas ®m 33m xm ma m :zc cm> »man ; Maj Ly HM mH mL 3n mc 00 w u cmc Hmc wmc 03« w w mwm mwl .mm Ex ass amm mmm mHH En ax ®®gm mw 33 0H L0 wumc c0 0 Lm MM ML w mmm omH mM xm ma mmm ®®mm >n cm n >n0 Lv on ng eB om w cmzu Hmc mmm ch

w

mañz

mam

amw

egg

:i

m_

pywm

mmm

h mi sa mm m 33m , Lo po mc co u Lm HH ML w mmm

omH mM xm ma mmm ®®mm >n cm xnon y 3L 20 3, mc 00 v mco mcc mmm

ch cmc Hmc mmc 33m w mm sa mg zn maa mam Qmm ®®® Ex mp wtmm mmm u Lp mmL xm ma mz UL UM mm m Ncm m: _ mmm cm> »non Lp x03 3. mc 00 q _ P-J Pa l mm Lo z mm Cm cc h. 4H mM H3 m OZC JZZ H mzo mh U 0 >2 cm zoo .U Up Mm eM me L mLm mma uwcm> man »0 mm Hn on cm> msk .mE Mm map MLm mm mm aa s MmU UM> HUc

N mc map Lw HM ma mL m sa mxm an Lwøüøv LU E LyH 0:a w mEM Ly gus mxw

mmm

_1m

mm_

uoHL

ma

mswy.

si

sas

sam

mam

mañs

Hmp

oy.

mg

ass

mm

33m

Luc vaxm hm mc cm> »non * Han w ML HH Lm nm om Lum v mcu mcc c .mm

k m Ex UC an oc w m ncm Sa w.s mwn sa m, ®mm ns am hs mv. svvn mm mm es HMU UM> HUC

H na Mag E HH mm mm . sam ass Ex yh msN mn HL UO w mm am mp mm mx ass vw 33 m. L0 wumc co u mmc Lm MN ML w UM qum Hm

omH w LL MM xm ma mum mwc Sá > cm on >U ij go nm om Lum q u mc cc Hm mc hm

m

cmum

gm

wwwmcm

wmeL

xm

cF

mom

mzc

mFo

zmwh

"

m>

2cm

zoo

:i

was

gsm

pan

na

mma

ñaon

mcy

Low

sä

wo#

czo

sm

HmyO

F

:i ass saa _ wjon m mL mM HM LwN EM m mcy Law Ex wo vcs os m Mac h så ses sma k mg uan mmm acw Lo* :i cm> HLU *0 MC JO EM HMN

OF sou cos Lam a ñwxmq mc nam m .mm

Lo pum cc øo Lm HH ML » :M n up mm : :# HE nun na num ML m mm ao ñcm > Hc me >xs x as ss m mmc Hm cc mc u m oom c3 LWH B mma aao n ma xm mco

002n32< m n M07 mammümñm 4103m001&.mmm&0. 201mm

N *20 mme zmñnmamm mmjw :m www» mmäwmmm nonámwnmñ áñcnr. swmoo p nrmzzmw mwmumsz uses rBHBHHmmmm ma sas :3 mmqgmm

m mms 2 mmwm.muama 000% »wcnr.zmm00 M wzwmm mxwm zmwnmnm mwmsa ?mugwpmmmm ma SSG :3 mmqtm ä nxmjjmw mmm.mzz m.mmererHH< om mmm m<mam3m 4:0 mmjmwmw 307mmmH03 w103 ärm Mzwmj<wmsm suüj *rm *mornwnmw smsmumüm Om ärm 003nmswmm Mm www» ärm ñmwwmüwwwñx 0% *Jm mmm: m<mwm3m Hm mmwwmmmn&01< än mxnmwwmjá . arm 001% Om *Jm m<mwm3 *rm* ämncMwmm 30m mäwmnñwon Hm wjm mmmnoozjmnüoñ 30% »m mcngmná wo 00010mH03 30:03 30& 201mm ärm: *Jm owmwnmñw meWHUD nonnmnw01.

003003< m :mmm 0 003303 nonjmnwow m0? mmm man meárwjm *xum cmm s»&r _n anm.H:H&Hmww% *3010 8010 mm<müm nedjomwos nwowwmgm 2300: 2010 awmmwwomwwä ümncnma mmwmñ ñmacnwnm arm owpmpjmwww *so mmumñwwm mmm man Humárwnm 008m? mc00ww Uwzm än osm

003303 UH: :på: m mncmñm 33 070mm mümm swár 010 <0pwmmm

mxomnw arma ärm wñcnr mamwnm um ñcznwnm.oosnmn< 3 103m m0 nmwwmn mocUHm 003003m&w03m :Hd: H3 www m 003300«01m 3 man: 003wpnmñwon. *Jm áñmemñ mmm 3mwmcsnáuon mwmjmw »3 ärm wwmnñOW 000 M: ärm mmjw< 0030H3mwwonm *tüjma 0:* *0 cm cnjmwmeHm acw áo 003300w01 UH: 010mmwmwr.azm m<müm3 Emm 30: nrmzmmm m0 »:m& 000:

mm3wñmeHmw man aowp< :mn Hám 0:: Emünwnm Hnmwnmáow H: *rm mrmum 0% mHam 030m <HmHUHm *0 rm 01H<mw *jwocmj »30 100% \Hms 301707 maa *30m wññmnmm303& :mm sovrma mconmmmmcww<.

arm 003nmnwmm w man 0 *Im* :mm wjm mmumjmwm Hmo r nonnmnwow 10000* *Jaa 00010mH03 UTOmegm mmew UC* 30W mm<mñm .003300&01m wñm njmjmma mä 30m* 0300 m <mmw.003umnw U :mm onww onmñmwmm 030 <001 man apa 30% 30001* m < 003300ñ01 01 0%301 mmm10100wmgm. OOEUwzw m 8300. mwmo :wa onmwmwmm mmm onpw 03m <mmü :ma 30

UñOUHmBm »0 70007* man mwmo 30 añmwwmw nosnmnwowm .

20 mnmnwmw gmunñmnwjnm mozmacwm mumnwmwww m 1 »mm Emm Cmma 0% msw Om arm nosnmnwmm mxnmnw wow 003ums< 0 www* :mn mumnwmw *www

mncwn3mzñ áo ormar wjm mmm .Hrwm Emm 003m 0300 m <mmw »ommájmw

50%: :jmmp 0103 nwmmmmm3üww m07 omnmñmw Uñmrm »jmumnáH03.

20 amwmw

Tmnøwámu m aon% Ujmr

nonwwowwmü

Km 000mCmm om mmnwoñm *30% 2010 ?mpwwma *0 »mm 5010 xnmn* m01 m mwanm ommm H: no3umj< w sjmñm 03m Om ärm mm 000030 Hamnáw<m umnmCmm Om m UmWanmjä mmwmm

mwmnmw %0 *30 jmmcwmwwjm <mw<m.

8:03 Bmwmcnnwuon »m »anwnmwmuu *Jm uñw< um 0% www 003Umnwmm Gujåchm *jmwñ ocwjmw Hm Mä 000c1m sjwwm uñw<wnu.Hm áümwwmñ Bmwmcnoåwon Hm »nuwnmüma mmámw noznmnwwsm wjm wwmwwmj w wwmwwm 003300»01 Hm »jmumnáma man ?mnocnwma.

zo 0100Hm3m :vw: mwmn»1030030&00 01 wmuwo mñmncmjnw

Hañmemümjnm Emñm ñmnowñma UK 03% üm §30 003umjwmm.

3. MAINTAINRBILITY (DURABILITY,SERUICEABILITY)

Hll companies claim that the readiness of the system is easily checked by observing the ABS warning lights.No other checka are made by the drivers.

Only one company (C) makes regular checka by means of special instruments provided by the ABS - manufacturer.This is done once a year.Company D has a service contract that includes the

ABS-systems.

The ABS -manufacturers provide a one year warranty including new parts and labour

None of the companies found it possible to give an answer to the question of the life of an antilock system in service.âll systems were still in operation although som parts had been replaced.

Company H had replaced one tractor sensor due to defective wire

caused by mechanical damage due to bad installation,two tractor controllers and one semitrailer oontroller.two of these were changed after only two months of operation and one ( on a

tractor ) efter 4 years of service.nfter initial troubles

mentioned earlier with the UBG connectors these are changed less

than once a year

Company B has changed 2 sensor exiter rings , one sensor due to cable damage and a warning indicator relay.

Company C has changed between lø-Zø sensors,about 10 controllers

and l@*15 ABseconnectors from 1982 to 2988.these were all on the

trucks and according to information from the DAF dealer

referable to sensor cable damage due to unsuitable installation which caused wear due to vibrations.These gav failure

indications which were difficult to trace and resulted in replacement of intact components before the real failure was

found.

Company D and E did not report any repairs

The trailer connectors wear out due to corrosion.and are easy

to replace.No other parts were reported to wear out No parts of the system were reported to be

serviced regularly

No parts were reported to need frequent adjustment.ndjustment

&. Hmcanzm mchmozzmza

oosnmnw ) amww<m1m wCTJmeüm. 37H3m7HH% OmmHnm mtñjwaWm. oosumnw m amww<m1m moon

nognmnw 0 amww<mñm moon man mmnmümw nm100 003Um3% 0 mmww<m1m mmsmwmp nmñmo

003nm3< m amww<m1m mmwummm man mmsmñmw 0m1m0 »30:3» Om Hama H: m *Kuhnwp ame<mwwu

003mm3< m n Mass wmxmmswüñmwwm1.0m åjm <mzwnwm gwpmmmm M§ Hm mmáwsmdmm *Jm* dax Hm *CHH< Hmamj man max m3uá<.

mognmnw w" mmaaaumusss rm 0: m éücnwlmcww áñmwwmw 003UH:m&H03. Om Jm <mjwnwm 3memmm H* Hm mmäw3mwma *rm* manad ms N Hm wcww< Fmams man ha N Hm :på: nmññumw pewa.

003um3< 0" mnsss rm 03 m W120? mcww áümwwmñ n03UH3mÖH03

Om *Jm 3memmm Må Mm mmáw3máma ärmá avec» ms N Hm maww Hmmm: man m8 N Hm spå: nmüwwmw Moma.

oosnmnw 0" mmsss rm 03 m wwcnr mcww ñwmwwmñ 0030H3máH03.H& smm 30* UnmmHUHm »0 mm* m3 mmeBmwm 0% *vw näOUOWWMO: mcHH< Hmamju nmñwwmw Hama man msnw< snwmwmm.

Oosum3< muzo mM®21mm oocwa Gm owámwnma.

memwncwñpmm QEWHJM anñoacnnwon Om mmm H: ärm onmñmdwonmu

1!!'lllIII'lllII..iglllli'llllx'ililll'11'lil!l|ll:!ltiillilillllll

203m Om ärm 003nmnwmm meOWWma max uwmmwncwåwmm. 01H<M3m nojuywwonmu

»HH nogumjwmm mxnmuá m :ma wasmüwa wosm awmñmjnm Q1H<H3® on wmnjmww vomum EH#3 mosm nwwm Hm 1HUCÖH03.3HH :www onmñwwwjm :namn www mmmm0: nonawñwonm :two: Hjowcamm mHHUUmü< üømam acw §0 mnos msn »mm »3 sm Ewnámñ nmüwoa mina endocmü *0 »U1HH.Emñ womam www mwmo Dawám mñmncmjw ncü 30% ümumñnma mm mmnmnwmwww

mwwunm1%.mm<m1m QOEUJHHH ammnmnwm smñm manocnñmñmn vw ärm

Zowsmmwms no3um3pmm 0 man 0 ñjocmj mnw mnmnHmwn :csnm1 nocpn 30%

um mw<m3.IHmj amnmwmñmwwon mäonm acw üo *jmmmwn nonmwwnwm :mm 30% amma ?mu01wma 3% *Jm a1w<m1m H3 wnw Om *rm 003Umnwmm.

5. PERFORMANCE

All companies reported that the drivers were very enthusiastic about driving ABS vehicles.

The main advantage reported by the drivers of all companies was the ability to brake on snow and ice without loosing steerability and stability especially without getting trailer swing or front axle breakaway.

None of the companies could report on specific near accidents avoided by ABS

In general none of the companies had observed any obvious change in driving behaviour though company A and C expressed a feeling that the drivers drove somewhat faster under severe road

conditions due to the higher confidence in being able to brake more efficiently without skidding.

None of the companies reported complaints about loss of brakes except for one case in company A on one dolly wheel due to malfunction in a controller unit.This was observed during a

coupling operation under en almost stationary condition.

None of the companies had any accidents to report for vehicles with or without ABS nor could they report on any improvement or

change in tyre wear,brake relinings ,brake repairs or other

ANNEX 1

1(2)

The University of Michigan

-

V

Transportation Research Institute

1901 han." Ruud. Åtm Ål'llf. Mtchlgnn QBIMJHO

What Will be Asked of the Users of Trucks

This section presents the types of questions that would be addressed to vehicle users.

These questions are divided into the following subject areas: (1) reliability, (2)

maintainability (durability, serviceability), (3) trucking environment, and (4) performance.

Relinbillty of ABS Systems

la. How often are repairs (other than routine maintenance) required?

lb. What is the mean time or distance between mall'unctions? (How often do

malfunctions occur?)

2. Which parts of the system require the most attention?

3 .> What kind ofmaintenance schedule is used to provide reliable operations?

4. Are deliveries delayed because of factors that are related to the antilock system? 1

5 . What does the driver do when a malfunction is indicated? How often do drivers

delay deliver-les to wait for service?

6. Any problems with electromagnetic or radio frequency interference (EMI/RFI)?

Maintainability (Durability, Scrviceability)

l . is the readiness of the antilock system easily checked by the driver?

2. What checks for proper operations of the system do your maintenance and service

i personnel make? Are these checks easy to make?

3 . What service does the vehicle or antilock manufacturer provide? Do they provide

warrantees?

4. What is the life of an antilock system in service?

5. Which parts have you replaced and how often (time or distance)?

6. Which parts wear out? Are these parts eaSy to replace?

_

7. Which parts of the system do you service? Are they easy to get at for service?

8. Which parts require frequent adjustment? How often are adjustments made? Are

the adjustments easy to make?

9. How often do you adjust wheel speed sensors?

Tracking Environment

1. What types of vehicles do you opemte? How many? How 'many of your vehicles

are equipped with antilock systems?

ANNEX 1 2(2)

3. *What is the amount of 'load in a typical delivery? What percentages of vehicle

kilometers are empty, panially leden, or fully iaden?

4. What diüculties were encountered during the time period when ABS was being

introduced into your operations?

1

I

5 . How many kilometers do your ABS-equipped vehicles accumulate each year? Your

non-ABS vehicles?

6. What is a typical delivery like? What kinds ofroads are involved? Approximater

how many routine stops are involved? Approximater how many downhill descents are

iHVOIVed? D0 mms-conflicts require high deceleration steps? Do you operatc wh^n the

road is slippery? Wet? Snowy? lcy?

Performance

l . Do your drivers like or complain about the antilock systems installed on their

vehicles?

.

.

2. Do your drivers observe improved braking perfnnnançe? Do the), know of

"accidents which didn't happen" because of ABS?

3. How many of these near misses have they had?

4. Do drivers drive ABS vehicles differently than those without? lf so, how?

5. Have there been any complaints about "loss of brakes"?

6. '15 the accidan record of your ABS vehicles different from your non-ABS vehicles?

7. Compared to non-ABS vehicles, are ABS vehicles under- or over-involved in

particular types of accidents?

8. Have Other aspects of your operation improved. changed, or degraded. eg., tire