Laboratory brake test variability Part 1: ISO friction coefficient. Part 2: ISO/PMP/SAE brake emissions

Transcription

1 Laboratory brake test variability Part 1: ISO friction coefficient Part 2: ISO/PMP/SAE brake emissions UN PMP 41 st meeting Ispra, Italy 13 th October 2016

2 summary ISO test variability TF brake performance testing Jaroslaw Grochowicz Carlos Agudelo & Shanglei Li Achim Reich Karl-Heinz Wollenweber Harald Abendroth Ford Motor Co. Link Engineering Company Continental Corp. ZF TRW Consultant (Chairman ISO SW brakes)

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4 2010 interlab accuracy study

5 Front brake Medium-size sedan FN3-57 caliper Low-steel pad 15-inch cast iron rotor McPherson knuckle All components measured and selected

6 Repeatability & Reproducibility for dynamometer controls Parameter Repeatability (within-lab) CD r Reproducibility (between-lab) CD R Initial speed (kph) Initial temp ( C) 4 8 Avg d press (bar) Avg d decel (m/s²)

7 Repeatability (Test-to-Test) for friction coefficient A B C D E 100% 99% 99% 93% 91% Percent of stops within 0.02 variation

8 Reproducibility (Dyno-to-Dyno) for friction coefficient Any test from lab A B 99 Compared to any test from lab A B C D E C D E Percent of stops within variation

9 Main sources of variation µ calculation and parameters Temperature control Airflow direction and volume

10 2011 DOE

11 DOE (7x2 FF) factors Factor Low A Brake Cooling 400 m³/h onto caliper DOE level High m³/h opposite to caliper B Environmental Cond cold/dry hot/humid C Kinetic Energy 90 % inertia 95 % braking speed D Pad Soak (5 ± 2) C at (40 ± 5) % RH cold/dry 110 % inertia 105 % braking speed (30 ± 2) C at (95 ± 5) % RH hot/humid E TC Location Lining TC Rotor TC F Caliper Drag Zero drag High drag G Burnish Cycles 32 snubs 192 snubs

12 Main effects for friction coefficient Main Effects Plot for Average µ Data Means Brake cooling Env ir. C ond. Energy lev el Low High C old/dry Hot/Humid Low P ad soak TC location C aliper drag High Mean C old/dry Burnish Hot/Humid Rotor Lining Low drag High drag Short Long

13 Effects on friction metrics for caliper drag 20 metrics > metrics < 0.02

14 Effects on friction metrics for cooling air temperature and humidy 15 metrics > metrics < 0.02

15 2013 V2D

16 Repeatability (vehicle and dyno) 89% < 0.02 vehicle 75% < % < 0.02 dyno 73% < 0.02

17 Correlation (vehicle-to-dyno) Front Axle Diff V1-D1 V2-D2 V4-D4 V5-D5 V6-D6 < % 100% 91% 98% 91% Rear Axle Diff V1-D1 V2-D2 V4-D4 V5-D5 V6-D6 < % 55% 84% 64% 66%

18 2014 M2M

19 ECE R90-A3 & A9 P/T, ISO JASO C406 SAE J2522, J2784 SAE J661 GB5763

20 Cumulative kinetic energy

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22 M2M fade & hot performance

23 Repeatability (T2T) test method %brake applications within friction ranges < > 0.04 SAE J R90-A9 P R90-A9 T GB R90-A ISO SAE J SAE J SAE J JASO C

24 Summary Coupon and drag tests, mainly type approval and QC Dynamometer testing closer to operational friction Dynamometer testing provides less variability

25 complete revision ISO document work into ISO TR advocate for improvement on other standards

26 ultimately, many software problems are people problems

27 Thank you! ISO test variability TF brake performance testing Jaroslaw Grochowicz Carlos Agudelo & Shanglei Li Achim Reich Karl-Heinz Wollenweber Harald Abendroth Ford Motor Co. Link Engineering Company Continental Corp. ZF TRW Consultant (Chairman ISO SW brakes)

28 proposal ISO/PMP/SAE test variability TF on brake emissions Carlos Agudelo Jaroslaw Grochowicz Link Engineering Company Ford Motor Co.

29 Cooperate on standardization Compete on implementation AUTOSAR AUTOmotive Open System ARchitecture

30 Thus far Related (but independent) studies and testing Performance and high energy dyno schedules Lack of standard city traffic dyno testing

31 What-not-how WP1 dyno test setup WP2 test procedure Enclosure & air handling WP3 test results City traffic test Debris sampling PMS specs Test conditions Measurements PN & PM Key metrics Correlations

32 VDA Vol 5 EN481- ISO 7708 EN12341 ISO Brake EUR ISO Dyno PMS ISO 3966 ISO ISO 5725 ISO 9169 ISO 8756 examples only

33 Open data Sync ISO, JSAE, SAE, and PMP Brake, dyno, and PMS agnostic Toxicology, health aspects, or chemistry Commercial vehicles Regulation or rulemaking

34 Further investigation and work Step 1 interlab labs 2 brakes 2-3 repeats Step 2 - ruggedness Step 3 interlab labs DOE for sensitivity Practice Tighten controls Final document and repeat (1 lab) Publication

35 one more thing

36 d > 2d > 8d flows on l/min

37 Collectives for braking speeds WLTP-Class 3 LACT FRACT

38 Collectives for deceleration LACT FRACT WLTP-Class 3

39 Collectives for rotor temperatures WLTP-Class 3 LACT FRACT

40 Collectives for pad temperatures WLTP-Class 3 LACT FRACT

41 LACT 3 x x 10 4 Particle count / 6 nm 10 µm Particle mass / 6 nm 10 µm

42 WLTP 4 x Particle count / 6 nm 10 µm Particle mass / 6 nm 10 µm

43 ISO fade 4 x Particle count / 6 nm 10 µm Particle mass / 6 nm 10 µm

44 Challenges & unknowns Customer usage and randomness of duty cycle Dyno/PMS validation and long-term r&r How to involve academia

45 Conclusions Need to better understand what the results mean Tribological explanations are still elusive Economics and global programs will lead integration

46 Cooperate on standardization Compete on implementation AUTOSAR AUTOmotive Open System ARchitecture

47 Thanks! UN PMP 41 st meeting Ispra, Italy 13 th October 2016