International Journal of Vehicle Performance (12 papers in press)
Measurement and Analysis of Performance of Mining Dump Trucks
by Pawan Kumar Yadav, Suprakash Gupta, Deepak Kumar
Abstract: Dump trucks are one of the widely used and capital-intensive heavy earth moving equipment in the mining industry. High-performance rate, good measurement practices and continuous monitoring of equipment performance are mandatory for the high-cost systems to be in the business. Defining the metrics of a performance measure (PM) is essential to monitor the performance of these equipments. This research proposes a methodology for measuring the performance of a dump truck. The proposed PM is derived from the Overall Equipment Effectiveness (OEE), a widely used PM in industrial and manufacturing industries, through modification of metrics. The modified PM is more comprehensive and incorporates the environmental aspects into the performance metrics. Commonly used PMs are based on the internal losses calculation, i.e. availability, performance, and quality losses; which neglected the operational effect beyond the system boundary, i.e. external losses. The proposed PM presents an approach that unites time performance, capacity performance as well as environmental performance. It has been illustrated with a case study in a large surface coal mine. Operational data have been analysed with SPSS. The findings are as follows
i. Dump truck performance decreases with its age,
ii. Availability and utilisation are the major cause of concern for poor performance
iii. Group-B dump trucks perform better than Group-A dump trucks.
The above findings are useful information in decision making.
Keywords: Dump truck; Performance Measurement; Environmental performance; Overall Equipment Performance Indicator (OEPI).
An Overview of Control Schemes for Improving the Lateral Stability of Car-Trailer Combinations
by Smitha Vempaty, Yuping He, Lin Zhao
Abstract: This paper reviews the state-of-the-art control schemes for enhancing the lateral stability of car-trailer (CT) combinations. Various studies have been conducted on lateral stability control of single-unit vehicles, e.g., cars. However, much less attention has been paid to lateral stability control of multi-unit vehicles, e.g., CT, which usually exhibit poor maneuverability in curved-path negotiations and low lateral stability under high-speed evasive maneuvers. The low lateral stability may lead to unstable motion modes, e.g., trailer-sway and jackknifing, causing severe accidents. To improve the lateral stability, various control schemes were designed considering relevant performance measures and evaluated using either numerical simulations or testing methods. Thus, the topics surveyed in this paper include: directional performance measures, evaluation methods, important parameters affecting the directional performance, and active control approaches for CT combinations. Important control schemes are emphasized and their features discussed and analyzed. As a result of the overview, future research efforts are identified.
Keywords: car-trailer combinations; lateral stability control; control actuation; vehicle-unit based control; control algorithm design; robust controllers.
Investigation on the Equivalent Mechanical Longitudinal Fluid Sloshing Model for a Partially Filled Tank Vehicle
by Xiujian Yang, Chuqi Feng
Abstract: This paper aims to investigate the equivalent mechanical model of longitudinal fluid sloshing for a partially filled tank vehicle. A one-degree-of-freedom (1DOF) mass-spring-damping (MSD) equivalent mechanical model proposed in the literature is first introduced and evaluated. To improve the precision of the MSD model, two 2DOF models those are the serial 2DOF (2DOF-S) model and the parallel 2DOF (2DOF-P) model have been formulated and evaluated. However, the 2DOF-S model and the 2DOF-P model can improve the precision only in some certain fill level conditions. Combining the merits of the two 2DOF models, a hybrid 3DOF (3DOF-H) model is proposed, formulated and evaluated. Several comparisons with other models demonstrate that the 3DOF-H model can provide rather satisfying precision in broad ranges of tank ellipticity and fill level. Finally, the proposed 3DOF-H MSD sloshing model is further evaluated from the viewpoint of vehicle dynamics response. It is revealed that the proposed 3DOF-H model can be easily used to integrate with vehicle dynamics to build a fluid tank vehicle model and the constructed tank vehicle model can reflect the basic dynamics property of a tank vehicle.
Keywords: Tank vehicle; Vehicle dynamics; Fluid sloshing dynamics; Equivalent mechanical sloshing model; Computational fluid dynamics; Genetic algorithm.
Review of Rapid Aging Testing Methods of Three-way Catalyst for Gasoline Engine
by Sheng Su, Yitu Lai, ChunXiao Hao, Pan Hou, Tao Lv, Yunshan Ge
Abstract: Recently, many advanced automotive companies around the world have developed rapid aging methods for their three-way catalyst converters (TWC). However, the systematic summary of related research progress is still lacking. Therefore, this work introduces TWC equivalent aging mechanism, classifieds and summarizes the current typical rapid aging technology for TWC. The primary aging of TWC on gasoline vehicle is thermal aging, and the equivalent aging theory is based on the Arrhenius equation. The current rapid aging technology for TWC, including vehicle aging, engine bench aging, and burner aging. There are three kinds of modes for engine bench aging, which are single mode, two-mode and multi-mode aging cycle. Introduces the common two-mode and multi-mode aging cycle in detail. Meanwhile, the paper compares the characteristics of different aging technologies. In general, engine bench aging methods and burner aging methods take less time, manpower and consumable cost than traditional vehicle aging, but there is a certain deviation from the actual vehicle aging effect.
Keywords: gasoline vehicle; three-way catalyst; Arrhenius; Rapid Aging; vehicle aging; engine bench aging; burner aging.
Heavy-duty diesel engine fuel consumption comparison with diesel and biodiesel measured at different altitudes
by Chunxiao Hao, Yunshan Ge, Xin Wang
Abstract: This paper devoted to a comparison of fuel consumption of a diesel engine fueled with diesel and biodiesel. Comparisons were conducted at sea level, 1600m and 3300m. A 6.7L, six cylinder turbocharged heavy-duty diesel engine was introduced. The BSFC over the full engine map were measured and plotted. The results indicated that the fuel consumption with diesel fueling increased with altitude in all the operating conditions except high-speed, high-load mode; while the fuel consumption with biodiesel fueling mainly increased with altitude under low-speed, low-load and middle-speed, low-load conditions. Under most of the testing conditions, the fuel consumption with biodiesel fueling was insensitive to the change of altitude. The comparison of fuel consumption between diesel and biodiesel fueling demonstrated that diesel was still the more economic option for diesel engines operating at sea level. However, biodiesel fueling could provide a better fuel economy under middle-speed conditions at high altitudes, particularly at 3300m.
Keywords: Fuel consumption; diesel engine; biodiesel; high altitude.
An Energy-Saving Strategy for Steering-Motors of Steer-by-Wire Vehicles
by Huiyong Zhao, Yuping He
Abstract: In a steering process, the steering-motor of a steer-by-wire (SBW) vehicle consumes energy. To facilitate energy efficiency analyses, the steering-motor energy consumption is split into two parts, which correspond to varied and constant steering-wheel angle operating condition, respectively. The former condition is a vehicle operational maneuver, in which steering-wheel angle varies continuously, whereas the latter is a constant-radius circular-curve negotiation, in which steering-wheel angle maintains constant. Analyzing the relation of steering-wheel angle with a road curvature, we propose an energy-saving strategy for steering-motors of SBW vehicles. The energy-saving strategy is featured with a concept, a hydro-mechanical locking device, and an SBW controller for the steering-motor unit. The feasibility and effectiveness of the energy-saving strategy is demonstrated using closed-loop simulations. To implement the closed-loop simulation, we combine the driver, vehicle, and curved road models generated in CarSim software with the steering-motor model and the SBW controller developed in Matlab/Simulink.
Keywords: Steer-by-wire vehicles; steering-motors; energy-saving strategy; hydro-mechanical locking device; locked rotor torque; circular-curve negotiation; closed-loop simulation.
Lightweight Design of Drive Axle Housing Based on Reliability
by Yang Chen, Xiandong Liu, Yingchun Shan, Tian He
Abstract: By introducing the influence of uncertain factors on the mechanical properties of drive axle housing, this paper investigates the method improving the reliability of the optimization scheme of a drive axle housing of off-road vehicle. Firstly, the finite element model of the drive axle housing is established, and its simulation is carried out according to the bench test standard. Then the Monte Carlo method is applied to study the influence of uncertain factors on the reliability of the axle housing. And the lightweight design of the axle housing is performed based on the 6? theory. The result shows that the weight of the axle housing is reduced by 12.48% under the premise of every performance with high reliability.
Keywords: drive axle housing; finite element analysis; reliability; lightweight design.
Special Issue on: Multibody System Algorithms in Vehicle Dynamics and Virtual Prototyping
Wheelrail wear simulation and rail cant optimisation based on railway vehicle dynamics
by Wei Li, Pu Wang, Shuguo Wang, Daolin Si
Abstract: A numerical prediction model for the wheelrail wear development on heavy-haul railway is established herein, and a corresponding programme is written using MATLAB. Using Archards material wear theory, wear distributions in the wheelrail contact patch and along the rail profile are evaluated via vehicletrack dynamics simulation and wheelrail rolling contact analysis. In the vehicle dynamics model, various structural components and complex nonlinear interactions between components are precisely simulated to guarantee consistency with reality. The established model is employed to study the influences of rail cant on the wheel-rail wear distribution and development. The following two main conclusions are drawn. On straight railway section, the wheelrail contact region and wear distribution become unreasonable when the rail cant exceeds 1/20. On curved section, the influences of rail cant on the wear of the inner and outer rails are different. The changes of rail cant also obviously impact the changing rules of wear with the vehicle speed. A rail cant of 1/30 is recommended for the curved section of heavy-haul railway.
Keywords: heavy haul railway; vehicle-track dynamics; wheel–rail contact; wear; numerical simulation; rail cant; optimisation.
Study the Dynamic behaviour of seven DOF of full car model with semi-active suspension system
by Hemanth Krishna, Shamanth Vasanth, Devaraj Sonnappa, Hemanta Kumar, Gangadharan KV
Abstract: This paper presents an investigation on the ride comfort and road-holding performance of a vehicle equipped with the semi-active suspension system. The full car semi-active suspension model with 7 degrees of Freedom (7 DOF) system is adopted for the study and a fuzzy-logic control strategy is considered for minimizing the effect of road disturbance on vehicle performance. The responses of a vehicle have been analyzed under the Indian average random road profile (ISO8608) against the conventional passive suspension system. The performance of the semi-active suspension system is evaluated by heave, roll and pitch acceleration of the vehicle body around its center of gravity. The performance of a vehicle with the semi-active suspension system has been compared with the response conventional passive suspension system. The result specifies that, the semi-active suspension system with a Fuzzy-logic controller reduces around 43 % of vibration amplitude at the resonance frequency of vehicle than the passive suspension system.
Keywords: Full car; MR damper; Modified Bouc-wen; NSGA-II; optimization; fuzzy logic and Indian average road.
Research on Hierarchical Control Strategy of Electromagnetic Active Mounting System
by Zheming Chen, Heng Wang, Chenguang Lai
Abstract: In order to improve the vibration isolation performance of the automotive powertrain mounting system, a hierarchical control strategy is proposed according to the structural characteristics of the electromagnetic active mounting system and the influence of the dynamic characteristics of the actuator on the system control accuracy. Based on the analysis of the active mounting system 3 degree-of-freedom (DOF) 1/4 vehicle, the mathematical model of the mounting system and the electromagnetic actuator control circuit is derived. Guided by hierarchical control strategy, upper and lower controllers are designed for mount part of the active mounting system and actuator circuit respectively. The upper mounting controller is under LQR control with strong adaptability, fine robustness and easy implementation, and the weight coefficient of its performance index is optimized by genetic algorithm. The lower part of the actuator circuit is under simple and practical PID control and its parameters are optimized through particle swarm optimization algorithm. To verify the effectiveness of the control strategy, two typical working conditions are set for simulation research with the system input of the joint excitation of the engine and pavement. The results show that compared with the active mounting system under conventional control, the system designed according to the hierarchical control strategy can control different working conditions of the vehicle more precisely, which not only improves the vibration isolation performance of the powertrain mounting system to a certain extent, but also renders a better robustness and force tracking property.
Keywords: Automotive engineering; powertrain; electromagnetic actuator; active mount; LQR control; genetic algorithm; PID control; particle swarm optimization; hierarchical control; simulation analysis.
Performance evaluation of different centrifugal pendulum morphologies through multibody dynamics simulation
by Marco Cirelli, Ettore Pennestrì, Pier Paolo Valentini, Romualdo Paga
Abstract: This paper aims to evaluate the effectiveness of the centrifugal pendulum applied to an internal combustion engine as a vibration damper. In particular, a specific design strategy, based on an energy equivalence, is analyzed using a series of multibody simulations. A simplified model is initially discussed and different solution morphologies simulated. The present solution is based on the roller-in-slot centrifugal pendulum, designed to have the same kinematic behavior of lumped mass models. The reasons why the centrifugal pendulum has had in recent years numerous applications are evidenced, together with a discussion of some design strategies. The main characteristics and requirements of this vibration damper are presented. Simulation strategy is subsequently showed, with a description of all bodies, forces, and parameters used in the different systems analyzed. To assess the effectiveness of the design strategy, a comparison among the simulation results of the different solutions is offered.
Keywords: Centrifugal Pendulum; Vibration Absorber; Multibody Dynamics; Trapezoidal pendulum; Contact simulation; Equivalent mechanism;.
Special Issue on: Recent Advances in Energy-efficient Research for Vehicle Performance Improvement
Research on regenerative braking strategies for hybrid electric vehicle by co-simulation model
by Han Guo, Jianwu Zhang, Wenran Geng, Huijun Cheng, Haisheng Yu
Abstract: Regenerative braking is an important factor in improving hybrid electric vehicle fuel economy. This paper presents the simulation modelling of a power-split hybrid electric vehicle with different regenerative braking strategies. A co-simulation model is used to enhance the simulation capability for the hybrid vehicle performance and development of control strategy. AMESim is used to model the complex physical components including engine, transmission, motors, battery and hybrid vehicle, and the physical model is integrated with control model established by MATLAB/Simulink, which is required to operate the vehicle and the regenerative braking system through standard drive cycles. Simulation results show that a regenerative braking control strategy can recuperate significant amounts of energy. Vehicle fuel economy in EV and HEV modes is improved significantly by coupling the proposed regenerative braking strategy.
Keywords: hybrid electric vehicle; regenerative braking; energy management; AMESim; MATLAB/Simulink.