Contour line of load transfer ratio for vehicle rollover prediction

2017 ◽  
Vol 55 (11) ◽  
pp. 1748-1763 ◽  
Author(s):  
Xinjie Zhang ◽  
Yi Yang ◽  
Konghui Guo ◽  
Jiming Lv ◽  
Tao Peng
Keyword(s):  
Load Transfer ◽  
Contour Line ◽  
Transfer Ratio ◽  
Vehicle Rollover ◽  
Rollover Prediction

Nonlinear Active Rollover Prevention Control Strategies for a 5-Axle Tractor/Semitrailer

2001 ◽  
Author(s):  
A. Scott Lewis ◽  
Moustafa El-Gindy
Keyword(s):  
Active Control ◽  
Load Transfer ◽  
Sliding Mode ◽  
Control Strategies ◽  
Lateral Load ◽  
Lateral Acceleration ◽  
Computer Simulation Model ◽  
Parameter Uncertainties ◽  
Transfer Ratio ◽  
Vehicle Rollover

Abstract This paper presents new active control strategies to prevent heavy vehicle rollover and focuses mainly on cases of maneuver-induced rollover such as rollover in cornering and lane-change maneuvers. Two performance measures as control strategies are explored: the lateral load transfer ratio and the trailer lateral acceleration. A nonlinear 75,000 pound 5-axle tractor/semitrailer computer simulation model has been used to demonstrate the effectiveness of the proposed active control system. A new non-linear sliding mode controller has been designed and found to be effective in improving the dynamic performance and roll stability, regardless of parameter uncertainties, such as tires or suspension characteristics. The controller torque requirement is limited by the differential dynamic braking forces that the tractor drive axles are able to produce as a function of the applied dynamic loads and road surface condition. The results show that with this new controller, the vehicle lateral acceleration can be controlled to prevent rollover without significant change of the vehicle trajectory when active yaw torque is applied to the tractor drive axles. Also, simulation results indicate that the vehicle rollover might be prevented using either the lateral load transfer ratio or the lateral acceleration at the trailer centre of gravity as control strategies.

Detection of Vehicle Tripped and Untripped Rollovers by a Novel Index With Mass-Center-Position Estimations

2017 ◽  
Author(s):  
Fengchen Wang ◽  
Yan Chen
Keyword(s):  
Load Transfer ◽  
Center Of Mass ◽  
Roll Motion ◽  
Mass Center ◽  
Motion Models ◽  
Center Position ◽  
Before And After ◽  
Vehicle Rollover ◽  
Lift Off ◽  
Rollover Index

This paper presents a novel mass-center-position (MCP) metric for vehicle rollover propensity detection. MCP is first determined by estimating the positions of the center of mass of one sprung mass and two unsprung masses with two switchable roll motion models, before and after tire lift-off. The roll motion information without saturation can then be provided through MCP continuously. Moreover, to detect completed rollover statues for both tripped and untripped rollovers, the criteria are derived from d’Alembert principle and moment balance conditions based on MCP. In addition to tire lift-off, three new rollover statues, rollover threshold, rollover occurrence, and vehicle jumping into air can be all identified by the proposed criteria. Compared with an existing rollover index, lateral load transfer ratio, the fishhook maneuver simulation results in CarSim® for an E-class SUV show that MCP metric can successfully predict the vehicle impending rollover without saturation for untripped rollovers. Tripped rollovers caused by a triangle road bump are also successfully detected in the simulation. Thus, MCP metric can be successfully applied for rollover propensity prediction.

scholarly journals Continuous Damping Control for Rollover Prevention with Optimal Distribution Strategy of Damping Force

2020 ◽  
Vol 10 (20) ◽  
pp. 7230
Author(s):  
Xu Zhang ◽  
Chuanxue Song ◽  
Shixin Song ◽  
Jingwei Cao ◽  
Da Wang ◽  
...  
Keyword(s):  
Load Transfer ◽  
Optimal Distribution ◽  
Damping Force ◽  
Damping Control ◽  
Rollover Prevention ◽  
Vehicle Rollover ◽  
Left And Right ◽  
Vehicle Suspension System ◽  
Dangerous Condition ◽  
Force Compensation

Vehicle rollover has always been a highly dangerous condition that can cause severe traffic casualties. In this work, a 14-degree-of-freedom vehicle model in MATLAB/Simulink is constructed with the vehicle suspension system dynamics. The validity of the model is verified by comparing with the CarSim model. Then an optimal distribution of damping force strategy with continuous damping control is proposed by combining the traditional lateral load transfer ratio control with optimized equations of suspension damping force. The damping force compensation of the left and right sides is the core of the optimal distribution of damping force strategy. The effectiveness and optimization effect of the optimal distribution of damping force strategy is proved by the simulation results under the fishhook and crosswind tests. The result shows that continuous damping control has evident control effects on vehicle rollover compared with passive suspension. The optimal distribution of the damping force strategy with continuous damping control has a great better performance than traditional continuous damping control, and it provides a certain assistance to vehicle handling stability.

Research on TTR and Roll Stability Control of Heavy Vehicle

2013 ◽  
Vol 380-384 ◽  
pp. 601-604
Author(s):  
Hong Yu Zheng ◽  
Yu Chao Chen
Keyword(s):  
Early Warning ◽  
Control Algorithm ◽  
Load Transfer ◽  
Reference Model ◽  
Stability Control ◽  
Heavy Vehicles ◽  
Lqr Control ◽  
Moment Distribution ◽  
Vehicle Rollover ◽  
The Moment

Because of the sensitive factors, such as the larger loads, higher mass center and relatively narrow tread in comparison with the height of heavy vehicles that have the poor dynamic rollover stability. This paper set of anti-rollover LQR control algorithm based on early warning. The model-based early rollover warning algorithm utilize the TruckSim® models and early warning reference model to predict the impeding vehicle rollover time in advance and told the driver the warning signals so that drivers had enough time to take appropriate measures to prevent vehicle rollover that called time to rollover (TTR), thereby greatly improving the vehicles active safety performance of the heavy vehicles. As to the anti-rollover LQR control algorithm, the principle was to use the optimal additional yaw moment obtained from the control algorithm and then made it reasonable impose the corresponding wheels by taking the moment distribution methods based on the differential braking for the purpose of reducing the risk of rollover. The simulation results show that the algorithm was presented in this paper can effectively reduce the lateral load transfer ratio and actively void the occurrence of rollover accidents.

Parameter Identification of Heavy Commercial Vehicle Rollover Prediction Model

2010 ◽  
Vol 439-440 ◽  
pp. 854-858
Author(s):  
Tian Jun Zhu ◽  
Chang Fu Zong
Keyword(s):  
Prediction Model ◽  
Parameter Identification ◽  
Commercial Vehicle ◽  
Model Simulation ◽  
Experiment Data ◽  
Vehicle Rollover ◽  
Ground Test ◽  
Simulation Results ◽  
Rollover Prediction ◽  
Heavy Commercial Vehicle

This paper presents the parameter identification technology of heavy commercial vehicle rollover prediction. In this study, a nonlinear truck model has been established for the rollover threat prediction. In order to achieve valid and representative truck model as close to the target real truck as possible, a set of key parameters are identified from experiment data collected from real truck ground test. At the last, the vehicle prediction model simulation results compared with the experimental results, it is shown that the prediction model can be accurately predicted the rollover dangerous state.

scholarly journals Rollover Prevention Control for Autonomous Electric Road Sweeper

Electronics ◽  
2021 ◽  
Vol 10 (22) ◽  
pp. 2790
Author(s):  
Seongjin Yim ◽  
Wongun Kim
Keyword(s):  
Load Transfer ◽  
Center Of Gravity ◽  
Path Tracking ◽  
Constant Speed ◽  
Speed Profile ◽  
Tire Model ◽  
Vehicle Model ◽  
Transfer Ratio ◽  
Rollover Prevention ◽  
Bicycle Model

This paper presents a method to prevent the rollover of autonomous electric road sweepers (AERS). AERS have an articulated frame steering (AFS) mechanism. Moreover, the heights of the center of gravity of the front and rear bodies are high. As such, they are prone to rolling over at low speeds and at small articulation angles. A bicycle model with a nonlinear tire model was used as a vehicle model for AERS. Using that vehicle model, path tracking and speed controllers were designed in order to follow a predefined path and speed profile, respectively. To check the rollover propensity of AERS, load transfer ratio (LTR) based the rollover analysis was completed. Based on the results of the analysis, a rollover prevention scheme was proposed. To validate the proposed scheme, a simulation was conducted using a U-shaped path under constant speed conditions. From the simulation, it was shown that the proposed scheme is effective in preventing AERS from rolling over.

Active vehicle rollover control using a gyroscopic device

2016 ◽  
Vol 230 (14) ◽  
pp. 1958-1971 ◽  
Author(s):  
Behrooz Mashadi ◽  
Morteza Mokhtari-Alehashem ◽  
Hamid Mostaghimi
Keyword(s):  
Load Transfer ◽  
Fuzzy Controller ◽  
Equations Of Motion ◽  
Gyroscopic System ◽  
Roll Torque ◽  
Rollover Risk ◽  
Vehicle Rollover ◽  
Vehicle Motion ◽  
Lift Off ◽  
Two Phases

A gyroscopic system is designed and utilized as an actuator for the prevention of vehicle rollover. The vehicle motion before rollover and during rollover is considered in two phases: before lift-off of the wheels and after lift-off of the wheels. The lateral load transfer ratio is used to identify the time when the wheels lift off the ground. Based on the equations of motion for the vehicle on two wheels, an imminent rollover algorithm is designed to specify the rollover risk. A fuzzy controller that determines the required roll moment to stabilize the vehicle is designed. A gyroscopic package is designed to apply the corrective roll torque directly on the rolling mass of the vehicle in the opposite direction to the rollover moments. The performance of the proposed system is investigated by simulating some severe manoeuvres, and the results show that the system is able to stabilize the vehicle successfully.

Coordinated Control of Steering and Anti-Roll Bars to Alter Vehicle Rollover Tendencies

1998 ◽  
Vol 124 (1) ◽  
pp. 127-132 ◽  
Author(s):  
Allan Y. Lee
Keyword(s):  
Traffic Safety ◽  
Load Transfer ◽  
Highway Traffic ◽  
Safe Operation ◽  
National Highway Traffic Safety ◽  
Active Systems ◽  
Active Devices ◽  
Dynamic Testbed ◽  
Vehicle Rollover ◽  
Active Controls

A Variable Dynamic Testbed Vehicle is presently being built for the National Highway Traffic Safety Administration. It will have four-wheel steering, front and rear active antiroll bar systems, four adjustable dampers, and other active controls. Using these active devices, we can alter the vehicle’s understeer coefficient, front/rear load transfer distribution in high-g lateral maneuvers, and roll mode frequency and damping. This study investigates how these active systems could be controlled to alter the vehicle rollover tendencies. In particular, we study how an increased front antiroll bar stiffness, in conjunction with an increased front damper rate and out-of-phase rear steering could improve vehicle rollover resistance and enhance vehicle safety. Similar but “reverse” algorithms could be used to artificially degrade the rollover resistance of a vehicle. Rollover-related accidents could then be studied using such a vehicle. Results obtained could also provide guidelines for the safe operation of the variable dynamic vehicle in limit lateral maneuvers.

scholarly journals Research method of vehicle rollover mechanism under critical instability condition

2019 ◽  
Vol 11 (1) ◽  
pp. 168781401882121 ◽  
Author(s):  
Bo Li ◽  
Shaoyi Bei
Keyword(s):  
Prediction Algorithm ◽  
Lateral Velocity ◽  
Full Account ◽  
Rollover Risk ◽  
Proposed Model ◽  
Critical Instability ◽  
Vehicle Rollover ◽  
Shift Experiment ◽  
Rollover Prediction ◽  
The Impact

In this article, a novel rollover prediction algorithm is developed for application on vehicles with large lateral velocity and high center of gravity. Lateral energy is the direct cause of rollover. Rollover prediction model is proposed by taking full account of the impact of the pavement, tire, and suspension and realizes the estimation of the vehicle lateral energy. By calculating the ratio of real-time lateral energy reserve and rollover threshold, the degree of rollover risk is obtained. The double-shift experiment and the Fishhook experiment are performed to verify the accuracy and suitability of the proposed model, and the proposed prediction is 0.2 s ahead of the actual liftoff situation and 0.45 s ahead of the actual rollover situation; therefore, the proposed rollover model can be regarded as an effective method.

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