SAWE Ground Vehicles https://www.sawe.org Society of Allied Weight Engineers, Inc. Sat, 04 Jul 2026 18:51:02 +0000 en-US hourly 1 https://wordpress.org/?v=7.0.1 231197347 3856 Weight Management of Ground Vehicles: A Mass Properties Control Framework for Road, Off-Road, and Special-Purpose Platforms https://www.sawe.org/product/3856-weight-management-of-ground-vehicles-a-mass-properties-control-framework-for-road-off-road-and-special-purpose-platforms/ Fri, 29 May 2026 16:35:21 +0000 https://www.sawe.org/?post_type=product&p=11472 Paper
Hans-Peter Dahm: 3856. Weight Management of Ground Vehicles: A Mass Properties Control Framework for Road, Off-Road, and Special-Purpose Platforms. 2026.

Abstract

Ground vehicles are frequently managed by curb mass, gross vehicle mass, or payload, but those scalar measures do not adequately control the engineering risk created by the distribution and maturity of mass. This paper presents a practical mass properties engineering framework for weight management of ground vehicles, including passenger cars, trucks, buses, motorcycles, electric bicycles, construction machines, special-purpose vehicles, and tracked platforms. The objective is to convert weight management from late-stage reporting into a closed-loop control process that supports architecture decisions, homologation, stability, braking, steering, energy use, payload, and lifecycle configuration control. The proposed approach combines top-down allocation of mass, center of gravity, axle loads, wheel loads, inertias, and reserves with bottom-up roll-ups from computer-aided design, bills of material, supplier data, and physical measurement. It distinguishes current mass from forecast mass, mass growth allowance from uncertainty, and certification limits from engineering margins. The method uses a defined mass state, a vehicle-family-specific risk register, a gate-based verification plan, and an escalation path whenever not-to-exceed values, axle reactions, center-of-gravity limits, or stability constraints are threatened. The central finding is that the best ground-vehicle program is not necessarily the lightest program; it is the program whose mass properties are controlled at the right level of maturity for each decision. For passenger cars and performance vehicles, the dominant risks are variant accretion, battery placement, unsprung mass, and inertia drift. For trucks and buses, payload, axle-load reserve, bodybuilder integration, roof-mounted systems, and rollover sensitivity dominate. For two-wheel vehicles, rider, battery, and luggage locations must be treated as part of the system. For construction and tracked vehicles, implement position, ballast, soil pressure, and transport configuration require explicit mass states. The paper concludes with an implementation checklist, for example status record, and peer-review checklist intended for adaptation to specific ground-vehicle programs. Keywords: mass properties engineering; weight management; ground vehicles; center of gravity; axle loads; moments of inertia; mass growth; uncertainty; vehicle development; verification.]]> Paper
Hans-Peter Dahm: 3856. Weight Management of Ground Vehicles: A Mass Properties Control Framework for Road, Off-Road, and Special-Purpose Platforms. 2026.

Abstract

Ground vehicles are frequently managed by curb mass, gross vehicle mass, or payload, but those scalar measures do not adequately control the engineering risk created by the distribution and maturity of mass. This paper presents a practical mass properties engineering framework for weight management of ground vehicles, including passenger cars, trucks, buses, motorcycles, electric bicycles, construction machines, special-purpose vehicles, and tracked platforms. The objective is to convert weight management from late-stage reporting into a closed-loop control process that supports architecture decisions, homologation, stability, braking, steering, energy use, payload, and lifecycle configuration control. The proposed approach combines top-down allocation of mass, center of gravity, axle loads, wheel loads, inertias, and reserves with bottom-up roll-ups from computer-aided design, bills of material, supplier data, and physical measurement. It distinguishes current mass from forecast mass, mass growth allowance from uncertainty, and certification limits from engineering margins. The method uses a defined mass state, a vehicle-family-specific risk register, a gate-based verification plan, and an escalation path whenever not-to-exceed values, axle reactions, center-of-gravity limits, or stability constraints are threatened. The central finding is that the best ground-vehicle program is not necessarily the lightest program; it is the program whose mass properties are controlled at the right level of maturity for each decision. For passenger cars and performance vehicles, the dominant risks are variant accretion, battery placement, unsprung mass, and inertia drift. For trucks and buses, payload, axle-load reserve, bodybuilder integration, roof-mounted systems, and rollover sensitivity dominate. For two-wheel vehicles, rider, battery, and luggage locations must be treated as part of the system. For construction and tracked vehicles, implement position, ballast, soil pressure, and transport configuration require explicit mass states. The paper concludes with an implementation checklist, for example status record, and peer-review checklist intended for adaptation to specific ground-vehicle programs. Keywords: mass properties engineering; weight management; ground vehicles; center of gravity; axle loads; moments of inertia; mass growth; uncertainty; vehicle development; verification.]]> 11472 SAWE RP G-1, 2016: Mass Properties Control for Wheeled and Tracked Vehicles https://www.sawe.org/product/sawe-rp-g-1-2016/ Tue, 05 Apr 2022 21:44:00 +0000 https://www.sawe.org//?post_type=product&p=5722 Scope   This document covers standard mass properties statements for procurement of mass properties data for wheeled and tracked vehicles, states the principles followed in the formulation of these standards, and furnishes instructions where necessary for uniform compilation of the required mass properties statements and forms   Sufficient detail is included to cover the majority of components for most wheeled and tracked vehicles (including amphibians). Blank spaces are provided for "write-ins" to detail mass properties for advanced design vehicles, projected propulsion systems, etc. Care should be taken before adding a "write-in" to ascertain that reasonably appropriate terms are not already available for usage.   Concepts   The detail and group mass properties statement have been predicated on the following basic concepts:  
    • The primary purpose of the mass properties data are to provide information in the most advantageous form for development and improvement of wheeled and tracked vehicles (including amphibians) mass properties estimating methods and for mass properties control during design and construction of the vehicles. Such data and methods serve the significant functions of bringing avoidable adverse trends to light at an early stage, pointing out areas in which design mass properties control can be most fruitful, establishing realistic weight goals, and evaluating on a rational basis the weight cost of design features during the evolution of new or alternate configurations.
 
    • The secondary purpose of the mass properties data is to provide reasonably detailed information for engineering checking and reference purposes such as dynamic stability, grade ability, power analysis of components, flotation capabilities (in case of amphibians) etc.
  Principals   The following principles have been followed to implement the above basic concepts:  
    • A dual status system has been implemented, a weight status (code system) and a mass properties status.
 
    • The weight status (code system) has been implemented to make it easier to group the data to aid in locating the data and to help to establish the confidence level by identifying the stage of estimation, calculation or actual data.
 
    • In the weight status (code system), all weights have been broken down into functional and identifiable components which will permit and encourage the analysis of weight variations and stimulate development of lighter and more efficient vehicles.
 
    • Insofar as practicable, all tangible and readily identifiable components and provisions for a specific function or installation have been allocated to the functional group, regardless of geographic location and physical method of attachment. Where compromise of this principle was necessary because of multi-purpose function (supports, panels, etc.), items have been allocated geographically with as complete function isolation and identification as is possible.
 
    • The mass properties status consists of a major breakdown of all items in the vehicle that require individual mass properties (weight, center of gravity location and mass moment of inertia) for determining power requirements of motors, static balance, dynamic balance, dynamic stability, grade ability, flotation capabilities and any other engineering analysis requiring mass properties data.
 
    • The mass properties status must show the "weight empty" mass properties, the "basic weight" mass properties, the "curb weight" mass properties, the "design load weight" mass properties, the shipping mass properties and all the major components making up the above list.
 
    • For clarity a detailed mass properties status of major sub-groups, must be submitted on separate sheets (example---engine, transmission, differentials, main frame, radar, armament, etc.) when the sub-group is a mechanism requiring power analysis (except if the sub-group has been in production prior to the contract approval and qualified by the procuring agency) or when required by the contract specification.
 ]]> Scope   This document covers standard mass properties statements for procurement of mass properties data for wheeled and tracked vehicles, states the principles followed in the formulation of these standards, and furnishes instructions where necessary for uniform compilation of the required mass properties statements and forms   Sufficient detail is included to cover the majority of components for most wheeled and tracked vehicles (including amphibians). Blank spaces are provided for "write-ins" to detail mass properties for advanced design vehicles, projected propulsion systems, etc. Care should be taken before adding a "write-in" to ascertain that reasonably appropriate terms are not already available for usage.   Concepts   The detail and group mass properties statement have been predicated on the following basic concepts:  
    • The primary purpose of the mass properties data are to provide information in the most advantageous form for development and improvement of wheeled and tracked vehicles (including amphibians) mass properties estimating methods and for mass properties control during design and construction of the vehicles. Such data and methods serve the significant functions of bringing avoidable adverse trends to light at an early stage, pointing out areas in which design mass properties control can be most fruitful, establishing realistic weight goals, and evaluating on a rational basis the weight cost of design features during the evolution of new or alternate configurations.
 
    • The secondary purpose of the mass properties data is to provide reasonably detailed information for engineering checking and reference purposes such as dynamic stability, grade ability, power analysis of components, flotation capabilities (in case of amphibians) etc.
  Principals   The following principles have been followed to implement the above basic concepts:  
    • A dual status system has been implemented, a weight status (code system) and a mass properties status.
 
    • The weight status (code system) has been implemented to make it easier to group the data to aid in locating the data and to help to establish the confidence level by identifying the stage of estimation, calculation or actual data.
 
    • In the weight status (code system), all weights have been broken down into functional and identifiable components which will permit and encourage the analysis of weight variations and stimulate development of lighter and more efficient vehicles.
 
    • Insofar as practicable, all tangible and readily identifiable components and provisions for a specific function or installation have been allocated to the functional group, regardless of geographic location and physical method of attachment. Where compromise of this principle was necessary because of multi-purpose function (supports, panels, etc.), items have been allocated geographically with as complete function isolation and identification as is possible.
 
    • The mass properties status consists of a major breakdown of all items in the vehicle that require individual mass properties (weight, center of gravity location and mass moment of inertia) for determining power requirements of motors, static balance, dynamic balance, dynamic stability, grade ability, flotation capabilities and any other engineering analysis requiring mass properties data.
 
    • The mass properties status must show the "weight empty" mass properties, the "basic weight" mass properties, the "curb weight" mass properties, the "design load weight" mass properties, the shipping mass properties and all the major components making up the above list.
 
    • For clarity a detailed mass properties status of major sub-groups, must be submitted on separate sheets (example---engine, transmission, differentials, main frame, radar, armament, etc.) when the sub-group is a mechanism requiring power analysis (except if the sub-group has been in production prior to the contract approval and qualified by the procuring agency) or when required by the contract specification.
 ]]> 5722