EotProtn_MDD

Module Design Document

For

EotProtn

Jul 1, 2016

Prepared For:

Software Engineering

Nexteer Automotive,

Saginaw, MI, USA

Prepared By:

Spandana Balani,


Change History

SNo.DescriptionAuthorVersionDate
1Initial VersionSarika Natu(KPIT Technologies)1.001-Oct-2015
2Implemented SF018A design version 1.5.0SB2.001-Jul-2016


Table of Contents

1 EotProtn & High-Level Description 5

2 Design details of software module 6

2.1 Graphical representation of EotProtn 6

2.2 Data Flow Diagram 7

2.2.1 Component level DFD 7

2.2.2 Function level DFD 7

3 Constant Data Dictionary 8

3.1 Program (fixed) Constants 8

3.1.1 Embedded Constants 8

4 Software Component Implementation 9

4.1 Sub-Module Functions 9

4.1.1 Init: EotProtn_Init1 9

4.1.1.1 Design Rationale 9

4.1.1.2 Module Outputs 9

4.1.2 Per: EotProtn_Per1 9

4.1.2.1 Design Rationale 9

4.1.2.2 Store Module Inputs to Local copies 9

4.1.2.3 (Processing of function)……… 9

4.1.2.4 Store Local copy of outputs into Module Outputs 9

4.2 Server Runables 9

4.3 Interrupt Functions 9

4.4 Module Internal (Local) Functions 9

4.4.1 Local Function #1 9

4.4.1.1 Design Rationale 10

4.4.1.2 Processing 10

4.4.2 Local Function #2 10

4.4.2.1 Design Rationale 10

4.4.2.2 Processing 10

4.4.3 Local Function #3 10

4.4.3.1 Design Rationale 10

4.4.3.2 Processing 10

4.4.4 Local Function #4 11

4.4.4.1 Design Rationale 11

4.4.4.2 Processing 11

4.4.5 Local Function #5 11

4.4.5.1 Design Rationale 11

4.4.5.2 Processing 11

4.4.6 Local Function #6 11

4.4.6.1 Design Rationale 11

4.4.6.2 Processing 11

4.4.7 Local Function #7 11

4.4.7.1 Design Rationale 12

4.4.7.2 Processing 12

4.4.8 Local Function #8 12

4.4.8.1 Design Rationale 12

4.4.8.2 Processing 12

4.4.9 Local Function #9 12

4.4.9.1 Design Rationale 13

4.4.9.2 Processing 13

4.5 GLOBAL Function/Macro Definitions 13

5 Known Limitations with Design 14

6 UNIT TEST CONSIDERATION 15

Appendix A Abbreviations and Acronyms 16

Appendix B Glossary 17

Appendix C References 18

EotProtn & High-Level Description

The End of Travel Protection function specifies performance attributes as the steering system approaches the mechanical end of travel of the steering gear.

Design details of software module

Graphical representation of EotProtn

Data Flow Diagram

See FDD

Component level DFD

See FDD

Function level DFD

See FDD

Constant Data Dictionary

Program (fixed) Constants

Embedded Constants

Local Constants

ConstantValue
DAMPGPTSIZE_CNT_U082
DAMPGVEHSPDSIZE_CNT_U084
GAINVEHSPDSIZE_CNT_U085

Software Component Implementation

Sub-Module Functions

Init: EotProtn_Init1

Design Rationale

Refer FDD

Module Outputs

Refer FDD

Per: EotProtn_Per1

Design Rationale

EotProtn_Per1 function is divided into various functions to reduce the cyclomatic complexity.

The limiting of ‘EotAssiSca’ output is performed in SoftEndStop subsystem in FDD. But in code it is limiting calculations are done where the output is calculated i.e. FildEotGain function.

Store Module Inputs to Local copies

Refer FDD

(Processing of function)………

Refer FDD

Store Local copy of outputs into Module Outputs

Refer FDD

Server Runables

None

Interrupt Functions

None

Module Internal (Local) Functions

Local Function #1

Function NameEotVelImpctTypeMinMax
Arguments PassedHwAgEotCw_HwDeg_T_f32float32360900
HwAgEotCcw_HwDeg_T_f32float32-900-360
HwAg_HwDeg_T_f32float32-14401440
VehSpd_Kph_T_f32float320511
HwAgAuthy_Uls_T_f32float3201
MotVelCrf_MotRadPerSec_T_f32float32-13501350
Return ValueEotMotTqLim_MotNwtMtr_T_f32float3208.8

Design Rationale

None

Note: Outputs of “EotVelImpct” function is - EotMotTqLim_MotNwtMtr_T_f32.

Processing

Refer to the “EotVelImpct” subsystem of the Simulink model of the design

Local Function #2

Function NameLimPosnDetdTypeMinMax
Arguments PassedRackTrvlLimrRngEna_Cnt_T_loglbooleanFalseTrue
HwAgEotCw_HwDeg_T_f32float32360900
HwAgEotCcw_HwDeg_T_f32float32-900-360
HwAg_HwDeg_T_f32float32-14401440
Return ValueLimPosn_HwDeg_T_f32float32-14401440

Design Rationale

None

Note: Outputs of “LimPosnDetd” function is - LimPosn_HwDeg_T_f32.

Processing

Refer to the “LimPosnDetd” subsystem of the Simulink model of the design

Local Function #3

Function NameCalcEntrGainTypeMinMax
Arguments PassedHwAg_HwDeg_T_f32float32-14401440
VehSpd_Kph_T_f32float320511
LimPosn_HwDeg_T_f32float32-14401440
Return ValueEntrGain_Uls_T_f32float3201

Design Rationale

None

Note: Outputs of “CalcEntrGain” function is - EntrGain_Uls_T_f32.

Processing

Refer to the “CalcEntrGain” subsystem of the Simulink model of the design

Local Function #4

Function NameCalcExitGainTypeMinMax
Arguments PassedHwTq_HwNwtMtr_T_f32float32-1010
Return ValueExitGain_Uls_T_f32float3201

Design Rationale

Calculation of Filtered Handwheel torque is done after ‘CalcExitGain’ function is executed.

Note: Outputs of “CalcExitGain” function is - FildHwTq_HwNwtMtr_T_f32

Processing

Refer to the “CalcExitGain” subsystem of the Simulink model of the design

Local Function #5

Function NameCalcEotGainTypeMinMax
Arguments PassedEntrGain_Uls_T_f32float3201
ExitGain_Uls_T_f32float3201
Return ValueEotGain_Uls_T_f32float3201

Design Rationale

None

Note: Outputs of “CalcEotGain” function is - EotGain_Uls_T_f32

Processing

Refer to the “CalcEotGain” subsystem of the Simulink model of the design

Local Function #6

Function NameFildEotGainTypeMinMax
Arguments PassedEotGain_Uls_T_f32float3201
Return ValueEotAssiSca_Uls_T_f32float3201

Design Rationale

Limit of EotAssiSca is moved to local function FildEotGain.

Note: Outputs of “FildEotGain” function is - EotAssiSca_Uls_T_f32

Processing

Refer to the “FildEotGain” subsystem of the Simulink model of the design

Local Function #7

Function NameCalcEotDampgTypeMinMax
Arguments PassedHwAg_HwDeg_T_f32float32-14401440
VehSpd_Kph_T_f32float320511
HwAgEotCw_HwDeg_T_f32float32360900
HwAgEotCcw_HwDeg_T_f32float32-900-360
MotVelCrf_MotRadPerSec_T_f32float32-13501350
Return ValueEotDampgCmd_MotNwtMtr_T_f32float32-8.88.8

Design Rationale

None

Note: Outputs of “CalcEotDampg” function is - EotDampgCmd_MotNwtMtr_T_f32

Processing

Refer to the “CalcEotDampg” calculation of the Simulink model of the design

Local Function #8

Function NameEotActvCmdCalcTypeMinMax
Arguments PassedRackTrvlLimrDi_Cnt_T_loglbooleanFalseTrue
HwAgAuthy_Uls_T_f32float3201
VehSpd_Kph_T_f32float320511
HwAg_HwDeg_T_f32float32-14401440
MotVelCrf_MotRadPerSec_T_f32float32-13501350
LimPosn_HwDeg_T_f32float32-14401440
Return ValueEotActvCmd_MotNwtMtr_T_f32float32-8.88.8

Design Rationale

None

Note: Outputs of “EotActvCmdCalc” function is - EotActvCmd_MotNwtMtr_T_f32

Processing

Refer to the “EotActvCmdCalc” calculation of the Simulink model of the design

Local Function #9

Function NameSoftEndStopStCtrlTypeMinMax
Arguments PassedVehSpd_Kph_T_f32float320511
HwAgAuthy_Uls_T_f32float3201
EotProtnDi_Cnt_T_Loglboolean01
EotDetd_Cnt_T_Loglboolean01
HwAg_HwDeg_T_f32float32-14401440
FildHwTq_HwNwtMtr_T_f32float32-3.4E+383.4E+38
SysMotTqCmdSca_Uls_T_f32float3201
LimPosn_HwDeg_T_f32float32-14401440
Return ValueNonefloat32-8.88.8

Design Rationale

None

Processing

Refer to the “SoftEndStopStCtrl” calculation of the Simulink model of the design

GLOBAL Function/Macro Definitions

None

Known Limitations with Design

None

UNIT TEST CONSIDERATION

None

Abbreviations and Acronyms

Abbreviation or AcronymDescription
FDDFunctional Design Document

Glossary

Note: Terms and definitions from the source “Nexteer Automotive” take precedence over all other definitions of the same term. Terms and definitions from the source “Nexteer Automotive” are formulated from multiple sources, including the following:

  • ISO 9000

  • ISO/IEC 12207

  • ISO/IEC 15504

  • Automotive SPICE® Process Reference Model (PRM)

  • Automotive SPICE® Process Assessment Model (PAM)

  • ISO/IEC 15288

  • ISO 26262

  • IEEE Standards

  • SWEBOK

  • PMBOK

  • Existing Nexteer Automotive documentation

TermDefinitionSource
MDDModule Design Document
DFDData Flow Diagram

References

Ref. #TitleVersion
1AUTOSAR Specification of Memory Mapping (Link:AUTOSAR_SWS_MemoryMapping.pdf)Process release 04.02.01
2MDD GuidelineProcess release 04.02.01
3Software Naming Conventions.docProcess release 04.02.01
4Software Design and Coding Standards.docProcess release 04.02.01
5SF018A_EotProtn_DesignSee Synergy subproject version
Last modified October 12, 2025: Initial commit (1fadfc4)