Ranking Tires for Heavy Truck Steering Feel Performance Using a Simulation Model2

2006 ◽  
Vol 34 (1) ◽  
pp. 64-82 ◽  
Author(s):  
S. L. Haas
Keyword(s):  
Vehicle Dynamics ◽  
Performance Metrics ◽  
Steering System ◽  
Lateral Acceleration ◽  
Steering Wheel ◽  
Dynamics Model ◽  
Objective Testing ◽  
Steering Feel ◽  
Wheel Torque ◽  
Heavy Truck

Abstract The effects of seven different tire sets on heavy truck steering feel characteristics were demonstrated from objective testing. Also, the steering behavior and vehicle dynamics were modeled in order to determine how well the resulting simulations could rank the steering performance of the tire sets relative to the objective results. The objective testing was performed using a 6×4 tractor with a two-axle flatbed semi-trailer. Measured data included steering wheel torque, steering wheel angle, and lateral acceleration behavior resulting from on-center-type steering tests. In addition, the hydraulic pressure from the power steering system was also measured. The tests consisted of multiple cycles at 0.2 Hz and ±0.2 g. Steering-related performance metrics were selected and calculated based on the interaction between measured parameters. The same test procedure was also applied using an analytical model of a steering system. The input was steering wheel torque, and outputs included the road wheel angles at the steer axle, which were then fed into a commercial vehicle dynamics model providing the vehicle dynamics behavior along with feedback required for the steering model (e.g., king pin moments). Tire loads and slip angles were also provided by the vehicle dynamics model and used as input to a tire model predicting tire force and moment behavior. The related metrics were subsequently computed and compared to the measured results. Effects of the different tire sets on steering characteristics were seen from both the objective and simulation tests. Seven performance metrics were applied in a ranking comparison between measured and modeled results. Correlation of the modeled to measured metrics ranged from R2 values of 0.40 to 0.99 for the seven metrics considered.

scholarly journals A Hysteresis-Based Steering Feel Model for Steer-by-Wire Systems

2017 ◽  
Vol 2017 ◽  
pp. 1-14
Author(s):  
M. Selçuk Arslan
Keyword(s):  
Mathematical Model ◽  
Steering System ◽  
Steering Wheel ◽  
Hysteresis Model ◽  
Steering Feel ◽  
Proposed Model ◽  
Steer By Wire ◽  
Wheel Torque ◽  
Tire Dynamics ◽  
The Mathematical Model

A mathematical model of steering feel based on a hysteresis model is proposed for Steer-by-Wire systems. The normalized Bouc-Wen hysteresis model is used to describe the steering wheel torque feedback to the driver. By modifying the mathematical model of the hysteresis model for a steering system and adding custom parameters, the availability of adjusting the shape of steering feel model for various physical and dynamic conditions increases. Addition of a term about the tire dynamics to the steering feel model renders the steering wheel torque feedback more informative about the tire road interaction. Some simulation results are presented to establish the feasibility of the proposed model. The results of hardware-in-the-loop simulations show that the model provides a realistic and informative steering feel.

Research of Electric Power Steering System Assistance Characteristic Based on the Identification of the Road

2013 ◽  
Vol 756-759 ◽  
pp. 4401-4406 ◽  
Author(s):  
Qiang Li ◽  
Chang Gao Xia
Keyword(s):  
Characteristic Curve ◽  
Steering System ◽  
Lateral Acceleration ◽  
Steering Wheel ◽  
Analysis Model ◽  
The Road ◽  
Power Steering ◽  
Resistance Torque ◽  
Wheel Torque ◽  
The Difference

Study of traditional assist characteristic cure does not take into account the difference of steering resistance torque caused by different road adhesion coefficient. Vehicle dynamics analysis model is established based on ADAMS/CAR. Simulation of steering wheel torque is realized under different road conditions. Departure from the ideal boost characteristics requirements and combined with ideal steering wheel torque under different speed and lateral acceleration., the article built assist characteristic curve under a certain road conditions. The system can real-time select the assist characteristic curve through identifying the vehicle traveling road conditions by the way of BP neural network. The theory provided a feasible method for the improvement of the EPS system performance.

Development of a real-time steering system model for driving simulators

2018 ◽  
Vol 233 (11) ◽  
pp. 2701-2713
Author(s):  
Cesare Certosini ◽  
Francesco Vinattieri ◽  
Renzo Capitani ◽  
Claudio Annicchiarico
Keyword(s):  
Real Time ◽  
Computational Cost ◽  
Steering System ◽  
Lookup Table ◽  
Lateral Acceleration ◽  
Steering Wheel ◽  
Human Beings ◽  
Driving Simulators ◽  
Power Steering ◽  
Wheel Torque

Driving simulators have boosted the vehicle design with the introduction of human beings in the simulation loop. For a realistic functioning, the steering system must provide an accurate behaviour, since the hand wheel is a crucial human interface. Despite a large diffusion of steering models, this paper deals with the creation of a specific solution for real-time applications, characterized by precise features as numerical stability and low computational cost. The proposed model is based on a physical structure and considers all the key phenomena, such as the system elasticities, the power steering effects and friction hysteresis, making the model more accurate in terms of steering wheel torque and lateral acceleration than other angle-driven models. Its two degrees of freedom design allows a proper behaviour of the power steering sub-model; another key aspect is the friction model: the use of the LuGre formulation greatly improves accuracy and stability in comparison to the lookup table friction models. Compared to the literature reference torque-driven model, it does not need the use of a torque sensor when implemented in driving simulators having an angle-driven formulation (the input of the steering wheel is its angle and the torque needed is its output), hence it is cheaper to implement; nevertheless, its accuracy is close to state-of-art reference. An original parametrization procedure is proposed since a generalized one is not available in literature; using a steering test-rig, all the model variables are defined. The validation phase combines offline and online simulations, assessing objectively and subjectively the model’s capabilities and showing accurate results in terms of steering wheel torque, lateral acceleration and steering feeling. In addition, a minor contribution of this paper shows how different analyses (steering effort evaluation, experimental data comparison or simulator feedback computation) require different output torques.

Study on decomposition and calculation method of EPS assist characteristic curve

2021 ◽  
pp. 095440702098706
Author(s):  
Xin Guan ◽  
Yu-Ning Zhang ◽  
Chun-Guang Duan ◽  
Wen-Liang Yong ◽  
Ping-Ping Lu
Keyword(s):  
Steady State ◽  
System Dynamics ◽  
Calculation Method ◽  
Characteristic Curve ◽  
Steering System ◽  
Steering Wheel ◽  
Driving Style ◽  
Steering Feel ◽  
Wheel Torque ◽  
Intermediate Variables

Steering feel is closely related to the matching of the EPS assist characteristic curve, however, due to the lack of theoretical basis for the design of the EPS assist characteristic curve, the steering feel can only be changed indirectly by adjusting the magnitude of assist, which is very difficult. To control steering feel directly and reduce the difficulty of adjustment, this paper proposes a decomposition and calculation method of the EPS assist characteristic curve. At first, the mechanism of the EPS assist characteristic curve is revealed. It is found that the process of designing and adjusting the EPS assist characteristic curve is a process of changing the corresponding relationship between the steering wheel torque and the steering motion intensity based on considering vehicle dynamic characteristics. On this basis, the driver’s desired steering motion intensity and the pinion angle position are taken as intermediate variables, the EPS assist characteristic curve is decomposed into three parts: driving style, steady-state inverse characteristics of chassis dynamics, and steady-state inverse characteristics of steering system dynamics. According to the designed driving style and the calibrated steady-state inverse characteristics of chassis dynamics and steering system dynamics, the EPS assist characteristic curve can be directly calculated. The test results show that the EPS system adopting assist characteristic curve calculated can realize the designed driving style and provide consistent and controllable steering feel on the premise of meeting the requirements of steering portability and road feel.

Design of an Optimal Control Strategy for an Active Front Steering System

2006 ◽  
Author(s):  
Avesta Goodarzi ◽  
Ebrahim Esmailzadeh ◽  
Babak Nadarkhani
Keyword(s):  
Optimal Control ◽  
Vehicle Dynamics ◽  
Steering System ◽  
Lateral Acceleration ◽  
Manufacturing Companies ◽  
Vehicle Dynamic ◽  
Steering Control ◽  
Optimal Control Strategy ◽  
Active Front Steering ◽  
Innovative System

The concept of active steering control (ASC) has been considered by several researchers as well as auto manufacturing companies during recent years. This innovative system permits any correction of the driver’s steering angle in order to achieve the desired vehicle dynamic behavior. An optimal control law to evaluate the steering angle’s correction of the front wheels, being part of an active front steering system (AFS), has been developed. For this purpose a specific lateral vehicle dynamics index is defined in which way that the minimization of the performance index lead to improved vehicle dynamics. The optimal values of the control law’s gains are determined analytically. The performance of the proposed control system has been verified using 8-DOF nonlinear vehicle dynamic model. The simulation results illustrate that considerable improvement in vehicle handling is achieved particularly for the cases of the low and mid-range lateral acceleration maneuvers.

Active Kinematics Suspension Integrating Milliken Moment Method in the Control Logic

2016 ◽  
Author(s):  
Isabel Ramirez Ruiz ◽  
Edoardo Sabbioni ◽  
Federico Cheli
Keyword(s):  
Vehicle Dynamics ◽  
Moment Method ◽  
Full Range ◽  
Operating Conditions ◽  
Lateral Acceleration ◽  
Steering Wheel ◽  
Slip Angle ◽  
Control Logic ◽  
Sideslip Angle ◽  
Vehicle Dynamics Control

The idea behind the active kinematics suspension is to enhance its performance of vehicle dynamics. This includes improve steady and dynamic limit stability and faster transient reaction through optimized lateral and longitudinal dynamics. The driver’s benefits are: improved safety and higher driving pleasure. To achieve more control over the position of the rear wheels and thus the tire contact patch on the ground, the active suspension introduces one independent linear actuator at each rear wheel that controls the wheels’ camber freely. This paper will present the vehicle dynamics control logic methodology of a rear active vehicle suspension implementing the Milliken Moment Method (MMM) diagram to improve the vehicle stability and controllability, achieving gradually the front and rear axle limits. A Multibody vehicle model has been used to achieve a high fidelity simulation to generate the Milliken Moment Diagram (MMD) also known as the CN-AY diagram, where the vehicle’s yaw moment coefficient (CN) about the CG versus its lateral acceleration (AY) is mapped for different vehicle sideslip angle and steering wheel angles. With the Moment Method computer program it is possible to create the limit of the diagram over the full range of steering wheel angle and side slip angle for numerous changes in vehicle configuration of rear camber wheels and operating conditions. The vehicle dynamics control logic uses the maps like a vehicle maneuvering area under different vehicle active configurations where vehicle’s control is most fundamentally expressed as a yawing moment to quantify the directional stability.

A Prototype Steering Weave Stabilizer for Automobiles

1991 ◽  
Vol 113 (1) ◽  
pp. 138-142 ◽  
Author(s):  
J. C. Whitehead
Keyword(s):  
High Speed ◽  
Steering System ◽  
Lateral Acceleration ◽  
Steering Wheel ◽  
Phase Lag ◽  
Vehicle Speed ◽  
Control Torque ◽  
Concentrated Mass ◽  
Wheel Rim ◽  
The Difference

A prototype high-speed steering stabilizer for automobiles applies transient steering torques so that the sum of natural steering restoring torque and the control torque is more nearly in phase with steer angle than the natural restoring torque alone. The resulting reduction in the phase lag from steer angle to restoring torque mitigates the steering weave mode. Since steering restoring torque is nearly proportional to vehicle lateral acceleration, weave controller circuitry could subtract instantaneous lateral acceleration from expected steady-state lateral acceleration calculated from steer angle and vehicle speed, and thence command a steering torque actuator depending on the difference signal. The prototype performs the same function using a concentrated mass on the lower steering wheel rim which is passively sensitive to both steer angle and lateral acceleration, thereby applying only transient steering torques in the desired manner at a vehicle speed of 30 m/s. The additional steering system inertia alone affects the weave mode, so a non-stabilizing configuration with the same mass distributed around the steering wheel rim is tested for direct comparison. The experimental data show a dramatic stabilization of weave for the configuration which applies control torque.

Influence of Front Wheel Alignment Parameters on Handling Stability of Vehicle Based on Joint Simulation

2014 ◽  
Vol 716-717 ◽  
pp. 832-836
Author(s):  
Hui Wang ◽  
Xiao Zhi Wang
Keyword(s):  
Steering System ◽  
Front Wheel ◽  
Front Axle ◽  
Lateral Acceleration ◽  
Steering Wheel ◽  
Initial Alignment ◽  
Vehicle Handling ◽  
Joint Simulation ◽  
Hydraulic Steering ◽  
Lane Change Test

This paper uses AMESim software to establish simulation model of SGA170 mine truck full hydraulic steering system, and validates the correctness of the proposed model. Through the joint simulation, vehicle steady circular test, double lane change test and steering wheel angle input test are verified. By changing the initial alignment parameters of front axle, vehicle handling performance are tested through the same simulation test, and yaw velocity, and the curves of lateral acceleration and vehicle roll angle describing vehicle handling stability are obtained, which provides a reference for the design and improvement of the similar mine truck selection.

Variable steering ratio control of steer-by-wire vehicle to improve handling performance

2019 ◽  
Vol 234 (2-3) ◽  
pp. 774-782
Author(s):  
Xiaodong Wu ◽  
Wenqi Li
Keyword(s):  
High Speed ◽  
Objective Evaluation ◽  
Angular Speed ◽  
Steering System ◽  
Lateral Acceleration ◽  
Steering Wheel ◽  
Handling Performance ◽  
Steer By Wire ◽  
Fuzzy Neural ◽  
Lane Change Test

To improve vehicle handling performance, a variable steering ratio characteristic for steer-by-wire system is designed. The steering ratio is adjusted by a compensating coefficient according to vehicle longitudinal speed and steering wheel angle. To evaluate the performance of vehicle with variable steering ratio, simulations are conducted based on an objective evaluation index, which consists of quadratic cost functions of vehicle lateral deviation, steering angular speed, vehicle lateral acceleration and roll angle. By using the optimized data from the simulation results, a Takagi-Sugeno fuzzy neural network is designed for the steering ratio control. In order to test and validate the proposed controller, a series of comparison experiments are conducted on a closed-loop driver-vehicle system, including lemniscate curve test and double lane-change test. The results demonstrate that compared with a conventional steering system with fixed steering ratio, the proposed system can not only improve steering agility at low speed and steering stability at high speed, but also reduce driver’s workload in critical driving conditions.

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