Lateral Load Transfer due to Sloshing Cargo in Partially Filled Containers

2019 ◽  
Author(s):  
Frank Otremba ◽  
José A. Romero Navarrete
Keyword(s):  
Load Transfer ◽  
Experimental Testing ◽  
Lateral Load ◽  
Safety Performance ◽  
Lateral Acceleration ◽  
Testing Device ◽  
Tilt Table ◽  
Theoretical Approaches ◽  
Acceleration Rate ◽  
Fill Level

Abstract The interaction of the liquid cargo and its carrying vehicle has been a common research subject, aiming at clarifying the potential effects of the mobility characteristics of such type of cargo, on the overall safety performance of the vehicle. While there has been extensive research on this topic, including both experimental and theoretical approaches, the comparative experimental testing of sloshing and non-sloshing cargoes has been only limited. In this paper, a scaled-down testing device that operates under the principles of a tilt table, is described and used to comparatively assess the effects, of a sloshing and non-sloshing cargo, on the lateral load transfer in the vehicle, as a function of the fill level and of the rate at which the lateral acceleration input is exerted on the vehicle-cargo system. Results suggest that the sloshing cargo generates greater load transfers, regardless of the fill level and acceleration rate input. As an average, the sloshing cargo generates a 14.75% greater load transfer.

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.

scholarly journals Modelling of a Partially Loaded Road Tanker during a Braking-in-a-Turn Maneuver

Actuators ◽  
2018 ◽  
Vol 7 (3) ◽  
pp. 45 ◽  
Author(s):  
Frank Otremba ◽  
José Romero Navarrete ◽  
Alejandro Lozano Guzmán
Keyword(s):  
Road Safety ◽  
Load Transfer ◽  
Dynamic Interaction ◽  
Performance Measure ◽  
Lateral Stability ◽  
Safety Level ◽  
Factors Associated ◽  
Braking System ◽  
Factors Influencing ◽  
Fill Level

Road safety depends on several factors associated with the vehicle, to the infrastructure, as well as to the environment and experience of vehicle drivers. Concerning the vehicle factors influencing the safety level of an infrastructure, it has been shown that the dynamic interaction between the carried liquid cargo and the vehicle influences the operational safety limits of the vehicle. A combination of vehicle and infrastructure factors converge when a vehicle carrying liquid cargo at a partial fill level performs a braking maneuver along a curved road segment. Such a maneuver involves both longitudinal and lateral load transfers that potentially affect both the braking efficiency and the lateral stability of the vehicle. In this paper, a series of models are set together to simulate the effects of a sloshing cargo on the braking efficiency and load transfer rate of a partially filled road tanker. The model assumes the superposition of the roll and pitch independent responses, while the vehicle is equipped with Anti-lock braking System brakes (ABS) in the four wheels. Results suggest that cargo sloshing can affect the performance of the vehicle on the order of 2% to 9%, as a function of the performance measure considered. A dedicated ABS system could be considered to cope with such diminished performance.

scholarly journals Research on Model Predictive Control for Automobile Active Tilt Based on Active Suspension

Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 671
Author(s):  
Jialing Yao ◽  
Meng Wang ◽  
Zhihong Li ◽  
Yunyi Jia
Keyword(s):  
Load Transfer ◽  
Ride Comfort ◽  
Active Suspension ◽  
Path Tracking ◽  
Roll Angle ◽  
Lateral Acceleration ◽  
Vehicle Speed ◽  
Model Predictive Controller ◽  
Advantages And Disadvantages ◽  
Predictive Controller

To improve the handling stability of automobiles and reduce the odds of rollover, active or semi-active suspension systems are usually used to control the roll of a vehicle. However, these kinds of control systems often take a zero-roll-angle as the control target and have a limited effect on improving the performance of the vehicle when turning. Tilt control, which actively controls the vehicle to tilt inward during a curve, greatly benefits the comprehensive performance of a vehicle when it is cornering. After analyzing the advantages and disadvantages of the tilt control strategies for narrow commuter vehicles by combining the structure and dynamic characteristics of automobiles, a direct tilt control (DTC) strategy was determined to be more suitable for automobiles. A model predictive controller for the DTC strategy was designed based on an active suspension. This allowed the reverse tilt to cause the moment generated by gravity to offset that generated by the centrifugal force, thereby significantly improving the handling stability, ride comfort, vehicle speed, and rollover prevention. The model predictive controller simultaneously tracked the desired tilt angle and yaw rate, achieving path tracking while improving the anti-rollover capability of the vehicle. Simulations of step-steering input and double-lane change maneuvers were performed. The results showed that, compared with traditional zero-roll-angle control, the proposed tilt control greatly reduced the occupant’s perceived lateral acceleration and the lateral load transfer ratio when the vehicle turned and exhibited a good path-tracking performance.

Automobile active tilt based on active suspension with H∞ robust control

2020 ◽  
pp. 095440702096620
Author(s):  
Jialing Yao ◽  
Meng Wang ◽  
Yanan Bai
Keyword(s):  
Robust Control ◽  
Degrees Of Freedom ◽  
Load Transfer ◽  
Ride Comfort ◽  
Simulation Analysis ◽  
Active Suspension ◽  
Roll Angle ◽  
Lateral Acceleration ◽  
Roll Moment ◽  
Roll Control

Automobile roll control aims to reduce or achieve a zero roll angle. However, the ability of this roll control to improve the handling stability of vehicles when turning is limited. This study proposes a direct tilt control methodology for automobiles based on active suspension. This tilt control leans the vehicle’s body toward the turning direction and therefore allows the roll moment generated by gravity to reduce or even offset the roll moment generated by the centrifugal force. This phenomenon will greatly improve the roll stability of the vehicle, as well as the ride comfort. A six-degrees-of-freedom vehicle dynamics model is established, and the desired tilt angle is determined through dynamic analysis. In addition, an H∞ robust controller that coordinates different performance demands to achieve the control objectives is designed. The occupant’s perceived lateral acceleration and the lateral load transfer ratio are used to evaluate and explain the main advantages of the proposed active tilt control. To account the difference between the proposed and traditional roll controls, a simulation analysis is performed to compare the proposed tilt H∞ robust control, a traditional H∞ robust control for zero roll angle, and a passive suspension system. The analysis of the time and frequency domains shows that the proposed controller greatly improves the handling stability and anti-rollover ability of vehicles during steering and maintains acceptable ride comfort.

Enhanced braking and steering yaw motion controllers with a non-linear observer for improved vehicle stability

2008 ◽  
Vol 222 (3) ◽  
pp. 293-304 ◽  
Author(s):  
Jeonghoon Song
Keyword(s):  
Load Transfer ◽  
Rear Wheel ◽  
Front Wheel ◽  
Driver Model ◽  
Lateral Acceleration ◽  
Slip Angle ◽  
Vehicle Stability ◽  
Motion Controller ◽  
Non Linear ◽  
Linear Observer

This study proposes two enhanced yaw motion controllers that are modified versions of a braking yaw motion controller (BYMC) and a steering yaw motion controller (SYMC). A BYMC uses an inner rear-wheel braking pressure controller, while an SYMC uses a rear-wheel steering controller. However, neither device can entirely ensure the safety of a vehicle because of the load transfer from the rear to front wheels during braking. Therefore, an enhanced braking yaw motion controller (EBYMC) and an enhanced steering yaw motion controller (ESYMC) are developed, which contain additional outer front-wheel controllers. The performances of the EBYMC and ESYMC are evaluated for various road conditions and steering inputs. They reduce the slip angle and eliminate variation in the lateral acceleration, which increase the controllability, stability, and comfort of the vehicle. A non-linear observer and driver model also produce satisfactory results.

scholarly journals Rollover Prevention System Dedicated to ATVs on Natural Ground

2012 ◽  
Vol 162 ◽  
pp. 505-514 ◽  
Author(s):  
Mathieu Richier ◽  
Roland Lenain ◽  
Benoit Thuilot ◽  
Christophe Debain
Keyword(s):  
Predictive Control ◽  
Control Algorithm ◽  
Load Transfer ◽  
Low Cost ◽  
Lateral Load ◽  
Dynamical Model ◽  
Rollover Prevention ◽  
Perception System ◽  
Prevention System ◽  
On Line

In this paper, an algorithm dedicated to light ATVs, which estimates and anticipates the rollover, is proposed. It is based on the on-line estimation of the Lateral Load Transfer (LLT), allowing the evaluation of dynamic instabilities. The LLT is computed thanks to a dynamical model split into two 2D projections. Relying on this representation and a low cost perception system, an observer is proposed to estimate on-line the terrain properties (grip conditions and slope), then allowing to deduce accurately the risk of instability. Associated to a predictive control algorithm, based on the extrapolation of riders action, the risk can be anticipated, enabling to warn the pilot and to consider the implementation of active actions.

System Identification and Lateral Dynamics of the Active Tilt-Controlled Electric Three Wheeler

2020 ◽  
Vol 142 (9) ◽  
Author(s):  
Jigneshsinh Sindha ◽  
Basab Chakraborty ◽  
Debashish Chakravarty
Keyword(s):  
Control System ◽  
System Identification ◽  
Load Transfer ◽  
Lateral Acceleration ◽  
Stable Operation ◽  
Technological Advancement ◽  
Track Width ◽  
Lateral Dynamics ◽  
Vehicle Trajectory ◽  
The Impact

Abstract Active tilt control system (ATC) is considered to be a prominent technological advancement in the three wheelers (3Ws), which improves the drive and comfort capabilities of 3W, leading to additional benefits of excellent maneuverability and small track width. An experimental prototype along with its simulation model is developed, to study the impact of the tilt actuation control system (TAS) and active steer (AS) system on the overall drive experience and stability improvement. A steering direct tilt control (SDTC) strategy is implemented on the vehicle, which allows stable operation of the system during the entire drive range. A transfer function (TF) of the TAS is estimated from the measurements on the prototype using the system identification tool. The derived TF is then utilized to investigate the response of the complete vehicle in terms of vehicle trajectory, perceived acceleration and load transfer across the rear wheels during the double lane change (DLC) and constant turn maneuvers. The results of the analysis indicate that the perceived acceleration felt by the driver is up to 45% less than the lateral acceleration along with up to 36% reduction in load transfer across the rear wheels.

A Numerical Investigation of Laterally Loaded Steel Fin Pile Foundations

2020 ◽  
Author(s):  
Te Pei ◽  
Tong Qiu ◽  
Jeffrey A. Laman
Keyword(s):  
Carrying Capacity ◽  
Load Transfer ◽  
Lateral Load ◽  
Steel Plates ◽  
Pile Foundations ◽  
Load Carrying Capacity ◽  
Element Analysis ◽  
Fea Model ◽  
Load Carrying ◽  
Maximum Improvement

Abstract The present study comprehensively evaluates the improvement in lateral load-carrying capacity of steel pipe piles by adding steel plates (fins) at grade level. This configuration of steel fin pile foundations (SFPFs) is effective for applications where high lateral loads are encountered and rapid pile installation is advantageous. An integrated finite element analysis (FEA) was conducted. The FEA utilized an Abaqus model, first developed to account for the nonlinear soil-pile interaction, and then calibrated and validated against well-documented experimental and filed tests in the literature. The validated FEA model was subsequently used to conduct a parametric study to understand the effect of fin geometry on the load transfer mechanism and the response of SFPFs subjected to lateral loading at pile head. The behavior of SFPFs at different displacement levels and load levels was studied. The effect of the relative density of soil on the performance of SFPFs was also investigated. Based on the numerical simulation results, the optimal fin width for maximum improvement in lateral load-carrying capacity was suggested and the underlining mechanism affecting the efficiency of fins was explained.

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