Taking you to the next level apply & Innovate 2012, IPG Technology Conference, Karlsruhe, 21 and 22 June 2012 itpms-in-the-loop Solution for Comprehensive Validation Tasks for indirect Tire Pressure Monitoring Systems According to the New ECE-R 64 Regulation Oliver Blanco-Hague, Coralie Dandre, MICHELIN Manufacture Française des Pneumatiques Charles Miquet, Bernhard Schick, IPG Automotive GmbH IPG Automotive GmbH 19.09.2012 1
Agenda TPMS-in-the-Loop Solution Introduction Direct and indirect TPMS systems TPMS Test procedure according to ECE R-64 Requirements for indirect TPMS HIL application itpms-in-the-loop solution for comprehensive Validation Tasks Conclusion IPG Automotive GmbH 19.09.2012 2
Introduction TPMS Will Be Mandatory by ECE-R 64 from 11/2012 Initial Situation Today ~ 15% of new vehicles are equipped with Tire Pressure Monitoring Systems (TMPS) TPMS will be mandatory by the new regulation ECE-R 64 from 11/2012 for vehicle in categories M1 (<3.5 T) and N1 equipped with single tyres Direct and indirect TPMS are existing and could be used OEMs are motivated to push to the indirect TPMS systems in order to saving money IPG Automotive GmbH 19.09.2012 3
Introduction TPMS Will Be Mandatory by ECE-R 64 from 11/2012 Challenges Indirect TPMS are cheaper but lead to extreme testing effort Huge numbers of vehicle variants, loads, driving conditions, road conditions, tire variants etc. must be approved to guarantee a robust system Sophisticated simulation tools for virtual test drive can support to reduce time and money within the whole validation process. A powerful simulation platform, a comprehensive test concept as well as reliable models especially a reliable tire model are needed IPG Automotive GmbH 19.09.2012 4
Direct and Indirect TPMS Systems Direct TPMS Systems Technology Tire pressure sensor mounted either on the inside of the rim or on the end of the valve stem inside the tire or outside. Information transmitted wirelessly to the receiver module using radio frequency communication Source : Dunn Tire Source : VDO Characteristics Higher costs Absolute pressure values, sometimes also the tire temperature Battery of the sensor has to be changed for such systems Source : Continental IPG Automotive GmbH 19.09.2012 5
Direct and Indirect TPMS Systems Indirect TPMS System Technology Indirect TPMS are embedded as ESC function TPMS function uses the wheel speed sensor signals to detect a possible under-inflated tire ESP ABS ASR VDC VAFs Wheel speed sensor (*4) ESP Characteristics TPMS Cheaper No absolute pressure values, only relative have to be reset by the driver once the tires are checked and all pressures adjusted correctly sensitive to the influences of different tires and external influences like road surfaces and driving speed or style IPG Automotive GmbH 19.09.2012 6
Direct and Indirect TPMS Systems Detection Methods of the Indirect TPMS Un-inflated tire detection by wheel circumference comparison Wheel speed sensor (*4) Different tire pressure ESP Lead to different roll radius Circumference Effect Pressure loss only in one tire detectable Source : Michelin Which lead to different wheel speeds Position of un-inflated tire couldn t be exactly detected Tire slip influences the detection quality IPG Automotive GmbH 19.09.2012 7
Direct and Indirect TPMS Systems Detection Methods of the Indirect TPMS Un-inflated tire detection using spectrum analysis Different tire pressure Tyre mode shapes Source : Michelin Eigen-frequency oscillation due to Inflation pressure variation A P Frequency f Frequency Effect Eigen-frequency is tire individual 35-50Hz Shift of eigen-frequency could be detected Position of inflated tire could be detected Pressure loss of more tire are detectable IPG Automotive GmbH 19.09.2012 8
Regulation ECE 64 TPMS Test Procedure According to ECE R-64 Ambient and road condition Ambient temperature between 0 C and 40 C Road test surface with good grip and dry during the test Vehicle conditions Usual load condition Vehicle speed Speed range from 40 km/h and 120 km/h for puncture test Speed range from 40 km/h and 100 km/h for the diffusion test and the malfunction test The whole speed range shall be covered during the test. IPG Automotive GmbH 19.09.2012 9
Regulation ECE 64 TPMS Test Procedure According ECE R-64 Warm-up Procedure and learning phase Drive the vehicle for a minimum of 20 minutes within the speed range and with an average speed of 80 km/h (+/-10 km/h) At the discretion of the Technical Service, where the driving test is undertaken on a track (circle/oval) with only turns in a single direction, then the driving test should be equally split (+/-2 minutes) in both directions Within the 5 minutes of completing the learning phase, measure the warm pressure of the tyre(s) to be deflated. The warm pressure shall be taken as the value Pwarm. This value will be used for subsequent operations. IPG Automotive GmbH 19.09.2012 10
Regulation ECE 64 TPMS Test Procedure According ECE R-64 Puncture test Deflation phase Deflate one of the vehicle's tyres within 5 min until Pwarm -20% (Ptest) or min. of 150 kpa Stabilization period 2-5 minutes Low tyre pressure detection phase TPMS shall illuminate the warning signal < 10 minutes after reducing the pressure Diffusion test Deflation phase Deflate all four tyres within 5 minutes until Pwarm - 20% - 7 kpa (Ptest) Stabilization period 2-5 minutes Low tyre pressure detection phase TPMS shall illuminate the warning signal < 60 minutes after reducing the pressure IPG Automotive GmbH 19.09.2012 11
Regulation ECE 64 TPMS Test Procedure According ECE R-64 Malfunction test Test procedure Simulate a TPMS malfunction, for example, by disconnecting the power source to any TPMS component, or disconnecting any electrical connection between TPMS components, or installing a tyre or wheel on the vehicle that is incompatible with the TPMS. Drive the vehicle for up to 10 minutes Failure detection TPMS shall Illuminate the warning signal < 10 minutes after generating the failure IPG Automotive GmbH 19.09.2012 12
Requirements for Indirect TPMS HIL Application Context : a Huge Variety of Configurations A huge validation effort is needed due to the large number of variants Tire / wheel combination Load conditions Vehicle variants Chassis variants Speed Ambient conditions (temperature) Roads Uneven Even Cross-country winding roads Autobahn IPG Automotive GmbH 19.09.2012 13
Requirements for Indirect TPMS HIL Application Requirements : a Powerful HIL Simulation Platform Software & Model Environment Vehicle Driver and maneuver Road Analysis tools Test automation HIL Tool Environment FailSafeTester tool Diagnostic tool support CCP/XCP and flash tool CAN/FlexRay/LIN tools HIL instruments HIL Testbench for ESP Simulation of all I/O signals CAN Communication Hydraulic signal acquisition Accurate wheel speed sensor module IPG Automotive GmbH 19.09.2012 14
Requirements for Indirect TPMS HIL Application Requirements : a Reliable Tire Model A reliable tire model is required High accurate physical tire model with realistic behavior. Temperature signal of inflation medium Tire Pressure modeling Physical pressure effect Tire pressure, which is function of tire temperature as input quantity of the tire model (not only parameter) Tire eigen-frequency modelling, which is pressure dependent Wheel speed [rpm] A P Frequency f Time IPG Automotive GmbH 19.09.2012 15
itpms-in-the-loop TameTire for itpms-in-the-loop TameTire model structure TameTire Data Base IPG Automotive GmbH 19.09.2012 16
itpms-in-the-loop Wheel Speed Sensor Signal Monitoring Wheel Speed sensor signal IPG M400 Wheel speed Pulse IPG Automotive GmbH 19.09.2012 17
itpms-in-the-loop itpms-in-the-loop Solution Software modules Hardware component User GUI Thermo-mechanical tire model Temperature effect Pressure effect TameTire Data Base IPG M400 Tire eigen-frequency module A P I (A) Wheel Speed signal Frequency f Pulse Shift t IPG Automotive GmbH 19.09.2012 18
Conclusion itpms-in-the-loop : the Solution for Indirect TPMS Validation TPMS system are mandatory for passenger cars from 11/2012 according to the ECE R-64 Indirect TPMS are cheaper but lead to extreme testing and validation effort A powerful simulation platform, a comprehensive test concept as well as reliable models especially a reliable tire model are needed itpms-in-the-loop module fulfills this sophisticated validation task for indirect TPMS IPG Automotive GmbH 19.09.2012 19