[PDF] NATO Reference Mobility Model. Edition I. Users Guide. Volume I

View - Download NATO Reference Mobility Model. Edition I. Users Guide. Volume I

Previous PDF

Next PDF

A HD TARADCOM

and L A~ Bo 0 ± Rol A W0R

T TECHNICAL REPORT

NO. 12503 •

NATO REFERENCE MOBILITY MODEL, EDITION I

USERS GUIDE

* VOLUME I

CONTRACT NO. DAAK30-77-C-0027

• : OCT 1979 , U .

PETER W. HALEY

* TARADCOM

M. PETER JURKAT

by PETER M. BRADY, JR.

STEVENS INSTITUTE OF TECHNOLOGY

: DAVIDSON LABORATORY

HOBOKEN, JJ 07030

"pproved for public release:1 'distribution unlimited.,

U.S. ARMY TANK-AUTOMOTIVE

RESEARCH AND DEVELOPMENT COMMAND

*) Warren, Michigan 48090 Approved for public release, distribution unlimited

II a. '13SOk

0

Technical Report 12503

NATO REFERENCE MOBILITY MODEL, EDITION I

USERS GUIDE

VOLUME I

OPERATIONAL MODULES

DA Project lL162601AH91

Prepared by

Stevens Institute of Technology

Davidson Laboratory

Castle Point Station

Hoboken, NJ 07030

Contract DAAK30-77-C-0027

OCT 1979

for US Army Tank-Automotive Research & Development Command

Warren, MI 48090

L

R-2058, VOLUME I

Page i

Operational Modules

TABLE OF CONTENTS

LIST OF FIGURES ........... ... ............................. ...vi LIST OF TABLES ...... ............. ..... ...................... vii LIST OF APPENDICES. ... ........................vii I. INTRODUCTION AND OVERVIEW ....... ...... ... ................. A. Background ............. ... .......................... I B. Modeling Off-Road Vehicle Mobility ........... ............. 5 C. Overall Structure of the INRMM ........... ................. 8 D. Model Inputs and Preprocessors ...... ................. ...12

I. Terrain ........... ..................... 12

2. Vehicle ........... ... ......................... ...13

3. Driver .......... ....... ....................... ... 15

4. Scenario .......... ....... ....................... ...15

E. Stand-Alone Simulation Modules ...... ................. ...17 I. Obstacle-crossing Module-OBS78B. .................. ...17

2. Ride Dynamics Module -- VEHDYN ........................ 18

3. Main Computational Modules -- NRMM ........ ........... 21

a. Areal Terrain Unit godule ...... ............ ...22 b. Road Module ............... .................... 28 F. Acknowledgements ........... ..... ....................... 30 II. ALGORITHMS AND EQUATIONS ......... .................... ..33 A. Control and I/0 Module ............. ................... ...33 I. Subroutine SCN -Scenario & Control Input ..... ........ 36

2. Subroutine VEH -Vehicle input ...... .............. ...36

3. Subroutine VPP -Vehicle Preprocessor Control .... ....... 36

4. Subroutine TERTL -Terrain Translator ............... ...36

a. Terrain Input/Translation Subroutine.MAP74 ........ 38 b. Terrain Input/Translation Subroutine MPRD74 ........ 39 c. Terrain Input/Translation Subroutine MAP7 ..... ....40

5. Subroutine AREAL -Areal Module Control ...... ........ 41

6. Subroutine ROAD -Road Moduje ...... ............... ...41

7. Subroutine BUFFO -Basic Output ..... .............. ...42

R-2058, VOLUME I

Page Ii

Operational Modules

B. Vehicle Preprocessor ......... ...................... ...43 I. Subroutine IIl -Units Conversion Routine ........... ...43

2. Subroutine 112 -Gross Combined Weight .............. ...44

3. Subroutine 113 -Maximum Tire Speed ................ ...44

4. Subroutine 114 -Maximum Path Width .... ............ ...46

5- Subroutine 115 -Tire Deflection Ratio .............. ...46

6. Subroutine 116 -Characteristic Length .............. ...46

7. Subroutine 117 -Ground Contact Area .... ........... ...47

8. Subroutine 118 -Controlling Lateral Distance ........... 47

9. Subroutine 119 -Maximum Rolling Radius ............. ...48

10. Subroutine 1110 -Maximum Braking Force .... .......... 48

11. Subroutine fill -Horsepower/ton ..... ............... 48

12. Subroutine 111.2 -Vehicle Cone Index in Fine Grained

Soil .... ....... ........... ..................... 49

13. Subroutine 1113 -Vehicle Cone Index in Coarse Grained

Soil. i *'**........................................ 51

14. Subroutine 1114 -Vehicle tone Index for Muskeg .......... 52

15. Subroutine 1115 -Combined Contact Pressure Factor .... 53

16. Subroutine 1116 -Power Train ...... .............. ...53

a. Subroutine TRAIN -Construction of Tractive Effort vs. Speed Curves ..... .............. ...54 (I) Subroutine AUTOM -Tractive Effort vs.

Speed of Vehicle with Automatic Trans-

mission and Torque Converter ............ ...56 (2) Subroutine STICK -Tractive Effort vs.

Speed of Vehicle with Manual Trans-

mission ......... ................... ..58 b. Subroutine FIT -Quadratic Curve Fit to Tractive Effort vs. Speed Relationship ............... ...58

17. Subroutine 1117 -Rotating Mass Factor .............. ...62

C. Terrain Preprocessor. ........... ............. ............. 63 D. Areal Module ........... ... .......................... ..68 I. Subroutine IVI -Obstacle Spacing and Area Denied ........ 68

2. Subroutine IV2 -Land/Marsh Operating Factors .... ....73

R-2058, VOLUME I Page iii

Operational Modules

3. Subroutine IV3 -Pull and Resistance Coefficients 74

a. Fine Grained Soil... ....... ...... ..... ..79 b. Coarse Grained Soil ......... ................. ...83 c. Muskeg ........... ........................ ...85 d. Shallow Snow ......... ..................... ...86

4. Subroutine IV4 -Summed Pull and Resistance Coefficient 88

5. Subroutine IV5 -Slip Modified Tractive Effort ........... 89

a. Subroutine TFORCF -Soil Limited Tractive Effort.. 95 b. Subroutine VELFOR -Maximum Velocity Overcoming a

Given Resistance ...... ................. .... 96

c. Subroutine SLIP -Powered Traction Element Slip for a Given Traction Coefficient ..... .......... 99 d. Subroutine QUADS -Quadratic Fit to 5 Points... ... 101

6. Subroutine IV6 -Resistance Due to Vegetation ......... ..101

7. Subroutine IV7 -Driver Dependent Vehicle Vegetation

Override Check ........... ...................... ..102

8. Subroutine IV8 -Total Resistance Between Obstacles ....102

9. Subroutine IV9 -Speed Limited by Resistance Between

Obstacles ........ .............................. 103

10. Subroutine IVIO -Speed Limited by Surface Roughness .... 104

11. Subroutine IVIl -Total Braking Force -- Soil/Slope/

Vehicle ............................... 105

12. Subroutine IV12 -Maximum Braking Force -- Soil/

Slope/Vehicle/Driver ....... ................... ..106

13. Subroutine IVl3 -Speed Limited by Visibility ...... 107

14. Subroutine IV14 -Selected Speed Between Obstacles ....... 108

15. Subroutine IVi5 -Maximum Speed Between and Around

Obstacles .......................................... 109

16. Subroutine IV16 -Obstacle Override Interference

and Resistance... ; .............. .................. Ill

17. Subroutine IV17 -Driver Dependent Vehicle Speed

over Obstacles ..... ............................ 112

18. Subroutine IV18 -Speed Onto and Off Obstacles ........... 113

19. Subroutine IV19 -Average Terrain Unit Speed While

Accelerating/Decelerating Between Obstacles .... ....... 117

R-2058, VOLUME I

Page iv

Operational Modules

a. Subroutine ACCEL -Time and Distance to

Accelerate from one Velocity to

Another ............. ...................... 123

b. Subroutine TXGEAR -Time and Distance in a

Gear ............ ....................... ..124

20. Subroutine IV20 -Kinematic Vegetation Override

Check ........... ....................... ..129

21. Subroutine IV21 -Maximurti, Average Speed ............ ..130

E. Road Module ................ .......................... ..132 I. Initialization ............. ...................... 133

2. Velocity Dependent Resistance ................. 133

a. Surface Resistance ................. 133 b. Aerodynamic Resistance ..... ............... ..135 c. Wheeled Axle Turning Resistance .............. ..135 d. Tandem Wheel Aligning Resistance .............. ..136

3. Non-Velocity Dependent Resistance ..... ............ ..136

a. Tracked Turning Resistance ..... ............. ..136 b. Rolling Resistance ................ 137 c. Grade Resistance ................. 138

4. Speed Limited by Resistance ..... ............... ..138

5. Speed Limited by Surface Roughness ................ ..138

6. Speed Limited by Sliding on Curves ................ ..139

7. Speed Limited by Tipping on Curves ................ ..139

8. Speed Limited by Visibility ........ ............... 139

9. Curvature Speed Limit ............ .................. 141

F. Linear Feature Module ................. .............. ..144 III. INPUTS AND OUTPUTS ............. ......................... ..145 A. Introduction ............. .......................... ..1145 B. Vehicle Data ............... .......................... ..147 C. Terrain Input -- Operational Modules ..... ............. ..154

I. Areal Terrain Input File -Class Interval

Values ............. ......................... ..154

R-2058, VOLUME I Page v

Operational Modules

2. Areal Terrain Input File -Real Values. .........157

3. Road Terrain Input File ... ...................... 160

D. Scenario and Control Input Data ................. 162 E. Output ..... .............. e............... 170 IV. REFERENCES. ......... .. .................. 173

R-2058, VOLUME I Page vi

Operational Modules

LIST OF FIGURES

I.A.1 -- Prospective Users of Vehicle Performance Prediction

Methodology. ....... ............. ..... 3

I.C.) -- General Organization of the Initial Nato Reference Mobility.Model ...... ....... ....................... 9 I.E.1 -- General Flow of INRMM Areal Module ........ .............. 23 II.A.1 -- Structure of Control and i/O Module .................. ..34 •I.A.2 -- Structure of'Subroutine TERTL ...... ................. ...37 II.B.1 -- Powertrain Calculation Logic of Subroutine 1116 ............ 55 I•.B.2 -- Plot of Tractive Effort vs. Speed Array .............. ... 59

11-B.3 -- Possible Anomaly in Quadratic Equation Fit to a Gear ..... 61

II.C. --Side View of an Obstacle .e...................... 64

11-C.2 -- Vehicle Approach to Obstacle ................. 65

•.D.1 -- Area Denied Due to an Obstacle ...... ................ ...72

11-D.2 -- SUBROUTINE IV5 -Slip Modified Tractive Effort ........... ...90

11.D.3 -- Tractive Effort vs. Speed Modification for Soil

and Slope ............... ............... 91

1.D.4 -- Flow Chart of SUBROUTINE IV18 ......... ................. 114

Il.D.5 -- Possible Speed Profiles Across an Obstacle and

Between Obstacles. ..................... 19

II.D.6 -- Speed Profile when Obstacle Approach Speed Cannot be Attained ........ ... .................. 121 II.D,7 -- Representation of Tractive Effort vs. Speed

Relation ..... ................... .124

R-2058, VOLUME I

Page vii

Operational Modules

LIST OF TABLES

I.C.1 -- Terrain, Vehicle, Driver Attributes Characterized in INRMM Mobility Model Data Base ................. ....11 II.D.l -- Slipperiness Conditions and Parameters ........... 81 I•E.l -- Curvature Speed Limits ............ ...........142 III.B.l -- Vehicle Input Data -- NAMELIST VEHICL ................ ...148 IIIC. -- Terrain Input File Structure ................ 155 III.C.2 -- Terrain Input File Structure -- Real Value ............ ...158 III•C.3 -- Terrain Input File Structure -- Roads ..... ............ 161 III.D.1 -- Control Input Data -Operational Modules NAMELIST CONTRL. ....... ..................... ...165 III.D.2 -- Control and Scenario Variables -Operational Modules NAMELIST SCENAR ............. ...................... 168

LIST OF APPENDICES

A. Listing of Program NRMM

B. Vehicle Input Files for Program NRMM

M60 AI (Tank) ................... ......................... B-2 M 151 (Jeep) ................. .......................... B-7

C. Terrain Input Files for Program NRMM

Areal Terrain Input File -- Class Interval Format -- File CKK. C-2 Road Terrain Input File-- Real Values Format -- File CKKRD. C-3

D. Sample Output of Program NRMM

Vehicle: M60 Al Terraih: CKK ...... ................. ...D-2 Vehicle: M60 Al Terrain: CKKRD ...... ................ ...D-lO Vehicle: M 151 Terrain: CKK. .......... ................ D-18 Vehicle: M 151 Terrain: CKKRD ...... ................ ...D-26

E. Possible STOP's in Program NRMM

Page 1

I INTRODUCTION AND OVERVIEW*

The NATO Reference Mobility Model ( NRMM) is a

collection of equations and algorithms designed to simulate the cross-country movement of vehicles. It was developed from several predecessor models, principally AMC-74 (Jurkat, Nuttall and Haley (1975)). This report, in several volumes, provides some background and motivation for most aspects of the model, and presents documentation for the coded version now available through the U. S. Army Tank-Automotive Research and Development Command (TARADCOM).

A. Background

* Rational design and selection of military ground vehicles requires objective evaluation of an ever-increasing number of vehicle system options. Technology, threat, operational requirements, and cost constraints change with time. Current postures must be reexamined, new options evaluated, and new trade-offs and decisions made. In the single area of combat Vehicles, for example, changes in one or another influencing factor might require trade-offs that run the gamut from opting for an air or ground system, through choosing wheels, tracks or air cushions, to designating a new tire. The former Mobility Systems Laboratory of the then U. S. Army Tank-Automotive Command (TACOM) and the U. S. Army Engineer Waterways Experiment Station (WES) are the Army agencies responsible for * This chapter is adapted from Jurkat, Nuttall and Haley (1975).

R-2058, VOLUME I Page 2

Operational Modules

conducting ground mobility research. In 1971, a unified U. S. ground mobility program, under the direction of the then Army Materiel Command (AMC), was implemented that specifically geared the capabilities of both laboratories to achieve common goals. As a first step in the unified program, a detailed review was made of existing vehicle mobility technology and of the problems and requirements of the various engineering practitioners associated with the military vehicle life cycle. One basic requirement was identified as common to all practitioners surveyed: the need for an objective analytical procedure for quantitatively assessing the performance of a vehicle in a specified operational environment. This is the need that is addressed to a substantial extent by the INRMM and its predecessors. In theory, a single methodology can serve some of the needs of all major practitioners, provided it relates vehicle performance to basic characteristics of the vehicle-driver-terrain system at appropriate levels of detail. Three principal categories of potential users of the methodology were identified: the vehicle development community, the vehicle procurement community, and the vehicle user community (Figure I.A.1). The greatest level of detail is needed by the design and development engineer (vehicle design and development community) who is inýerested in subtle engineering details--for example, wheel geometry, sprung masses, spring rates, track widths, etc.--and their

R-2058, VOLUME I

Page 3

Operational Modules

VEHICLE DESIGN AND VEHICLE PROCUREMENT VEHICLE USER

DEVELOPMENT COMMUNITY COMMUNITY COMMUNITY

Preparation of

Evaluation of

Strategic

Specifications Competitive Designs Selection of Mix

RQC's etc.

Vehicle Design Tactical

and 1. Route Selection

Development

2. Estimation of

Engineer Support

Vehicle Test

and

Evaluation

* PROSPECTIVE USERS OF VEHICLE PERFORMANCE PREDICTION METHODOLOGY

FIGURE I-A-1

interactions with soil strength, tree stems of various sizes and spacings, approach angles in ditches and streams, etc. At the other end of the spectrum is the strategic planner (user community), who is interested in such highly aggregated characteristics as the average cross-country speed of a given vehicle throughout a specified region--the net result of many interactions of the engineering details with features of the total operational environment. Between these two extremes, is the person responsible for selection of the vehicles whoquotesdbs_dbs27.pdfusesText_33

[PDF] BGV A5

[PDF] BGV B 3

[PDF] BGV B3 - IG Metall

[PDF] BGV D27 Flurförderzeuge

[PDF] BGV D44 Munition - arbeitssicherheit.de

[PDF] BGV-Elementarschutz zahlt den Schaden an Haus und Einrichtung

[PDF] bgv`PV - BATI CENTRAL Colmar

[PDF] BH - Compte rendu AGO

[PDF] BH 1er prix du concours « On écrit une Belle Histoire

[PDF] BH 3 prix du concours « On écrit une Belle Histoire

[PDF] BH 500-6 B 7735501023

[PDF] BH instructions mise à jour Budgetbox V2

[PDF] BH-D Grand Diamètre

[PDF] BH1-120B - aremeca instrumentation

[PDF] BHAGAVAD-GITA ——— UN EPISODE DU MAHÂBHÂRATA