Brake Effectiveness Evaluation Procedure SAE J2784 FMVSS 135 BRAKE MANUFACTURERS COUNCIL BMC TN S1

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Brke Effectiveness Evlution Procedure SAE J2784 FMVSS 135 BRAKE MANUFACTURERS COUNCIL BMC TN 08001 S1 This Brke Effectiveness Evlution Procedure Guide for vehicles with Gross Vehicle Weight Rting

1 Brke Effectiveness Evlution Procedure SAE J2784 FMVSS 135 BRAKE MANUFACTURERS COUNCIL BMC TN S1 This Brke Effectiveness Evlution Procedure Guide for vehicles with Gross Vehicle Weight Rting elow 3,500 kg uses test results from the SAE J2784 FMVSS 135 single ended inerti dynmometer test. The test results, comined with vehicle specific prmeters nd vehicle dynmics modeling, evlute the BEEP pss/fil criteri nd predict the conformnce confidence of friction mteril with the Federl Motor Vehicle Sfety Stndrd requirements for stopping distnce. The computer model ws vlidted using proving ground testing with fully instrumented vehicles.

2 BRAKE MANUFACTURERS COUNCIL A Product Line Group of Motor & Equipment Mnufcturers Assocition BMC BEEP Brke Effectiveness Evlution Procedure for Aftermrket Friction Product Performnce Chrcteriztion using the SAE J2784 FMVSS 135 inerti dynmometer test procedure Introduction The BMC Friction Mterils Committee resolves tht replcement rke friction mterils should not deteriorte vehicle rking performnce elow the pplicle Federl Motor Vehicle Sfety Stndrds, nd recognizes tht full vehicle or inerti dynmometer testing per SAE J2784 with peer reviewed engineering nd computer nlysis my e employed y mnufcturers of replcement friction mterils in mking good fith efforts to determine FMVSS conformnce confidence. To implement this ojective the BMC implemented the BEEP voluntry certifiction progrm dministered y SAE PRI. Being the only industry pproved nd peer reviewed progrm ville to the industry, the BMC decided to enhnce the BEEP progrm with the ddition of the SAE J2784 FMVSS 135 inerti dynmometer test procedure to ssess the BEEP pss/fil criteri for vehicles mnufctured fter These continuous efforts from the BMC lign with the government s strtegic frmework outlined on NHTSA Docket No The use of computer models, sound lortory testing results, pproprite engineering nlysis methods, nd vehicle specific prmeters, llows the rke or ppliction engineer to predict vehicle performnce nd determine the level of conformnce confidence for given comintion of friction mterils (on the front nd rer xles) reltive to the requirements of the Federl Motor Vehicle Sfety Stndrd FMVSS 135. Similr models re used throughout the utomotive industry to expedite the development nd evlution of friction mterils nd rke systems while reducing the overll costs relted to the testing ctivities nd ssocited resources efore forml relese for regulr production. This Guide ws developed fter extensive proving ground testing per the FMVSS 135 with fully instrumented vehicles nd lortory testing per the SAE J2784 FMVSS 135 test procedure to ensure the roustness of the model. To mke certin of the coverge of different rke systems, the tests used two vehicle rking system configurtions: Crossover vehicle with Electronic Brke Proportioning; disc rke on oth xles; Sedn vehicle with fixed rke proportioning; drum rke on the rer xle. The test progrm included three different friction mterils on ech xle: Originl equipment friction mteril; Aftermrket high friction mteril; Aftermrket low friction mteril. The methods presented on this technicl note follow the ojective of the Brke Mnufcturers Council's Friction Mteril Committee BMC/FMC: The BMC Friction Mterils Committee resolves tht replcement rke friction mterils should not deteriorte vehicle rking performnce elow the pplicle Federl Motor Vehicle Sfety Stndrds, nd recognizes tht full-vehicle or inerti-dynmometer testing per J2784 with peer-reviewed engineering nd computer nlysis my e employed y mnufcturers of replcement friction mterils in mking good-fith efforts to determine FMVSS conformnce confidence. BRAKE MANUFACTURERS COUNCIL Friction Mteril Committee 2

3 BMC B TN S1 BE EEP Guide FMVSS F Key elements of the SAEE J2784 sed BEEP B model he BEEP mod del determiness the ility of o friction mteril m to devvelop the requ uired rking torque t to meet the specifieed Th su ustined deceleertion require ement, when hving h known n rke on thee other xle nd d without exceeeding the dh hesion utiliztio on lim mit on either of the two xless (no wheel locck up). The folllowing comin ntions pply to o the differentt test sections depending d upo on th he type of rking system nd d its operting condition Two sets of clcultions required: r system; Fixed proportioning rke Electronic proportioning rking sysstem Two scenrios for rer rrke clcultions: Non proportioning vlve; Fixed proportioning (pressure reduccing) vlve. VW nd GVWR R): 1.3. Four scenrios for filed systems (t LLV Filed power rke p unit t GVWR; opertion nl with rer rke filed for front to rer rke system split s (II distriu ution); Rer rrke opertionl with front rke filed forr front to rer rke system split s (II distriu ution); One fro ont nd one rer rke opertionl only forr digonl rkke system split (X distriution n). Th he following sssumptions nd d simplifiction ns pply to thee BEEP model using SAE J FMVSS 135: Additionl rking or retrdtion forcess like engine n nd trnsmissio on rking pow wer, tire rollingg resistnce, eerodynmic drg forces, nd incresed tire to rod dhession s functiion of tire slip re not includeed in this modeel; n level for the clcultion c of ttinle deceelertion levelss; Use of 0.95 insted of 0.9 s the tire to rod dhesion e pplicle use nomiinl pedl forcee of 500 N with hout compensting for the driver's d effort to modulte the All rking events pedl force for ABS or vo oid excessive wheel w slip or locck up which vries s functtion of the fricttion mterils eing tested. The BEE EP model usses vehicle dy ynmics to predict idel rke lnce for dec celertions ove g-criticl g for AB BS or Electro onic Brke Proportioning system ms. The mod del is le to predict critic l sections like e Cold Efffectiveness, Filed F power ssist unit, n nd Hot perfformnce. BRA AKE MANUF FACTURERS S COUNCIL Friction Mte eril Committe ee 3

4 Figure 1 illustrtes the different options for the type of rke events, test sections, nd system conditions contemplted in the model. UMTRI limit Rer rke Rer prop Fully opertionl Decelertioncontrol t t LLVW & GVWR Rer rke Rer prop BEEP using SAE J2784 Pressurecontrol t t GVWR Rer rke Rer prop Power rke t t GVWR Rer rke Filed systems Hydrulic circuit t t LLVW & GVWR Front/Rer (II) split Digonl (X) split Rer rke Rer rke Rer prop Rer prop FIGURE 1. TYPES OF BRAKE EVENTS, TEST SECTIONS, SYSTEM CONDITION, AND BRAKE SYSTEM CONFIGURATION FROM FMVSS 135 AND SAE J2784 BRAKE MANUFACTURERS COUNCIL Friction Mteril Committee 4

Brke output torques BEEP model clcultions Determine loding nd rke system condition Comined rking forces (front nd rer) Tire to rod dhesion utiliztion on ech xle Determine limiting condition: rke

5 The flowchrt on figure 2 illustrtes the min steps nd inputs required to ssess the different pss/fil criteri for the BEEP model. Vehicle design or floor check prmeters Weights nd weight distriution CG loction, wheelse Brke pressure versus pedl force curves Brke sizes (front nd rer) SAE J2784 test Brke pressure nd torque ehvior Brke output torques BEEP model clcultions Determine loding nd rke system condition Comined rking forces (front nd rer) Tire to rod dhesion utiliztion on ech xle Determine limiting condition: rke torque output or dhesion utiliztion Vehicle dynmics Dynmic weight trnsfer G criticl Vehicle performnce prediction Estimte totl vehicle decelertion Determine conformnce confidence to FMVSS FIGURE 2. MAIN STEPS TO ASSESS THE BEEP PASS/FAIL CRITERIA 2. BEEP criteri for fully opertionl system 2.1. Rmp pplictions; University of Michign Trnsporttion Reserch Institute UMTRI limit during rmp pplictions to 12,000 kp. s shll not generte torque equivlent to decelertion level ove 1.0 g t LLVW nd rke pressure corresponding to 178 N of pedl force. This criterion pplies only to vehicles without ABS or Electronic Brke Proportioning BEEP criteri for decelertion controlled or pressure controlled rke pplictions. The test rke shll develop torque equivlent to the required sustined decelertion level from the corresponding section t GVWR or LLVW when using the seline vlues from the OE mteril on the reference xle (non tested xle) without exceeding pressure corresponding to 500 N of pedl force with the rke system fully opertionl. 3. BEEP criteri for filed systems 3.1. Pressure controlled rke pplictions power rke or power ssist unit filure. The test rke shll e le to develop torque equivlent to the required sustined decelertion level from the power rke unit filure section t GVWR without exceeding pressure corresponding to 500 N of pedl force with ny rke power ssist system fully depleted Decelertion controlled rke pplictions hydrulic circuit filure Front to rer (II) split. The test rke shll develop on the test xle (front or rer) torque equivlent to the required sustined decelertion level from the hydrulic circuit filure sections t GVWR or LLVW without exceeding pressure equivlent to 500 N of pedl force with the rke system fully opertionl Digonl (X) split. The test rke shll e le to develop torque equivlent to the required sustined decelertion level from the hydrulic circuit filure sections t GVWR or LLVW when using the seline vlues from OE mteril on the reference xle without exceeding pressure corresponding to 500 N of pedl force with the rke system fully opertionl. BRAKE MANUFACTURERS COUNCIL Friction Mteril Committee 5

6 4. BEEP structurl integrity criteri 4.1. Allowed: Detchment or frcture of ny component, such s rke springs, rke lining mteril, other thn minor crcks tht do not impir ttchment of the friction mteril to the cking plte or shoe tle; 4.2. Not llowed: Friction mteril ter out (complete detchment of lining from cking plte or shoe tle) exceeding 10% of ny individul friction mteril. 5. Test report A summry tle indicting the pss/fil for ech pplicle BEEP criteri. In ddition, s the min report for ech rke event with BEEP criteri the test report shll indicte: 5.1. Attinle vehicle decelertion clculted for the vehicle with the OE friction mteril on the other xle (non tested xle); 5.2. Percentge mrgin of conformnce (or non conformnce) confidence with the pplicle BEEP criteri; 5.3. Except for the hot performnce criteri #1 nd #2 which re very specific on the FMVSS 135 protocol, the ctul BEEP conformnce confidence is reported for the rke ppliction with the highest clculted decelertion vlue for tht specific section. This follows the FMVSS criteri tht "t lest one stop" needs to fulfill the requirement. Tles 1 nd 2 show smple summry with the pplicle BEEP pss/fil criteri for friction products meeting nd not meeting ll the BEEP requirements for vehicle with EBP nd with non ABS fixed rer rke proportioning, respectively. TABLE 1. SUMMARY TABLE WITH TEST RESULTS FROM A TEST MEETING ALL BEEP CRITERIA FMVSS 135 TEST ON FRONT BRAKE BRAKE MANUFACTURERS COUNCIL Friction Mteril Committee 6

7 TABLE 2. SUMMARY TABLE WITH TEST RESULTS FROM A TEST NOT MEETING ALL BEEP CRITERIA FMVSS 135 TEST ON FRONT BRAKE BRAKE MANUFACTURERS COUNCIL Friction Mteril Committee 7

8 Appendix A Minimum performnce requirements per the FMVSS 135 Tle A.1 shows the test sequence during SAE J2784 FMVSS 135 inerti dynmometer lortory test long with the mximum stopping distnce llowed during the vehicle test nd the corresponding sustined decelertion level. In order to otin the different sustined decelertion levels, the BEEP model uses the nominl test conditions (rke force uild up time nd rking speed) long with the mximum stopping distnce llowed for the specific section. The generl clcultion for the mximum llowed stopping distnce in meters (nd minimum stopping distnce for the recovery performnce section) during the vehicle test uses eqution A.1. S 2 V + V Eqution A.1 Where: V coefficient tht equls 0.1 to ccount for the distnce trveled during rking force uildup time is the rking speed in km/h coefficient tht vries s function of the mximum stopping distnce llowed. Coefficient is relted to the sustined vehicle decelertion 135 per eqution A.2. The individul vlues re specified on the FMVSS 135 protocol for ech section = Eqution A TABLE A.1. BEEP CRITERIA USING SAE J2784 FMVSS 135 INERTIA DYNAMOMETER TEST PROCEDURE Section Numer FMVSS 135 Reference Brking Speed V [km/h] Brke Appliction Control (IBT, Cycle Time, or Distnce) FMVSS 135 Required stopping distnce S [m] BEEP Required decelertion level 135 [g] Burnish t GVWR 80 IBT = 100 C (1) kp Adhesion Utiliztion Rmps t GVWR (2) kp Adhesion Utiliztion Rmps t GVWR 50 IBT = 65 C first, then 100 C 100 IBT = 65 C first, then 100 C Cold Effectiveness t GVWR 100 IBT = 100 C < 70 > High Speed Effectiveness t GVWR 160 IBT = 100 C < > 0.59 (80% V mx for V mx < 200 km/h) <0.1 V V Cold Effectiveness t LLVW 100 IBT = 100 C < 70 > High Speed Effectiveness t LLVW 160 IBT = 100 C < > 0.59 (80% V mx for V mx < 200 km/h) <0.1 V V Filed Antilock System t LLVW 100 IBT = 100 C < Hydrulic Circuit Filure t LLVW for front rkes Hydrulic Circuit Filure t LLVW for rer rkes Hydrulic Circuit Filure t GVWR for front rkes Hydrulic Circuit Filure t GVWR for rer rkes 100 IBT = 100 C < 168 > IBT = 100 C < 168 > IBT = 100 C < 168 > IBT = 100 C < 168 > Filed Antilock System t GVWR 100 IBT = 100 C < Cool Down t GVWR 5 Until 5 C ove cooling ir temp BRAKE MANUFACTURERS COUNCIL Friction Mteril Committee 8

9 Section Numer FMVSS 135 Reference Brking Speed V [km/h] Brke Appliction Control (IBT, Cycle Time, or Distnce) FMVSS 135 Required stopping distnce S [m] BEEP Required decelertion level 135 [g] 130 Wrm Up t GVWR 50 Until 65 t 60 seconds cycle time Filed Power Brke Unit t GVWR 100 IBT = 65 C first, then 100 C < 168 > Heting Snus t GVWR IBT = 55 C first, then cycle time of 45 seconds First Hot Stop t GVWR seconds fter the end of the lst snu from section 160 < < 110 > ( 1 / 2) First OR Second Hot Stop t GVWR seconds fter the end of section 170 < 89 > Brke Cooling Stops t GVWR 50 Cycle distnce = 1.5 km fter the end of section Recovery Performnce t GVWR Cycle distnce = 1.5 km fter the strt lst stop of section Finl Inspection for structurl integrity Not llowed: Friction mteril ter out (complete detchment of lining from cking plte or shoe tle) exceeding 10% of ny individul friction mteril Biliogrphy BMC, Aftermrket Friction Product Effectiveness Chrcteriztion Guide, BMC, Reserch Tringle, NC, 2002 Breuer, B. nd Bill, K. H. Brke Technology Hndook, SAE, Wrrendle, PA, 2008 Limpert, R. Brke Design nd Sfety, SAE, Wrrendle, PA, 1999 NHTSA, Stndrd No. 135 Light Vehicle Brke Systems, DOT, Wshington DC, 2005 NHTSA Docket No Recommended Best Importer Prctices To Enhnce The Sfety Of Imported Motor Vehicles And Motor Vehicle Equipment, DOT, Wshington DC, 2008 Roert Bosch GmH, Sfety, Comfort nd Convenience Systems, John Wiley & Sons Ltd., West Sussex, Englnd, 2006 SAE Brke Dynmometer Test Code Tsk Force, SAE J2784 FMVSS 135 inerti dynmometer test procedure, SAE, Wrrendle, PA, 2007 Additionl informtion: network.org/pri/ 1 BEEP criteri not ctul requirement for the FMVSS 135 vehicle test. 2 Using decelertion level equivlent to the mximum stopping distnce llowed during the Cold Effectiveness section t GVWR t 100 km/h; section Ditto footnote 2. BRAKE MANUFACTURERS COUNCIL Friction Mteril Committee 9

Solenoid Operated Proportional Directional Control Valve (with Pressure Compensation, Multiple Valve Series)

Solenoid Operated Proportional Directional Control Valve (with Pressure Compensation, Multiple Valve Series) Solenoid Operted Proportionl Directionl Control Vlve (with Pressure Compenstion, Multiple Vlve Series) Hydrulic circuit (Exmple) v Fetures hese stcking type control vlves show pressure compensted type