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

2017 ◽  
Vol 2017 ◽  
pp. 1-14
Author(s):  
M. Selçuk Arslan

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.

2006 ◽  
Vol 34 (1) ◽  
pp. 64-82 ◽  
Author(s):  
S. L. Haas

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.


2017 ◽  
Author(s):  
Jaepoong Lee ◽  
Sehyun Chang ◽  
Kwangil Kim ◽  
Bongchoon Jang ◽  
Dongpil Lee ◽  
...  

Author(s):  
Felix Heinrich ◽  
Jonas Kaste ◽  
Sevsel Gamze Kabil ◽  
Michael Sanne ◽  
Ferit Küçükay ◽  
...  

AbstractUnlike electromechanical steering systems, steer-by-wire systems do not have a mechanical coupling between the wheels and the steering wheel. Therefore, a synthetic steering feel has to be generated to supply the driver with the necessary haptic information. In this paper, the authors analyze two approaches of creating a realistic steering feel. One is a modular approach that uses several measured and estimated input signals to model a steering wheel torque via mathematical functions. The other approach is based on an artificial neural network. It depends on steering and vehicle measurements. Both concepts are optimized and trained, respectively, to best fit a reference steering feel obtained from vehicle measurements. To carry out the analysis, the two approaches are evaluated using a simulation model consisting of a vehicle, a rack actuator, and a steering wheel actuator. The research shows that both concepts are able to adequately model a desired steering feel.


2015 ◽  
Vol 2015 ◽  
pp. 1-17 ◽  
Author(s):  
Sheikh Muhammad Hafiz Fahami ◽  
Hairi Zamzuri ◽  
Saiful Amri Mazlan

In conventional steering system, a feedback torque is produced from the contact between tire and road surface and its flows through mechanical column shaft directly to driver. This allows the driver to sense the steering feel during driving. However, in steer by wire (SBW) system, the elimination of the mechanical column shaft requires the system to generate the feedback torque which should produce similar performance with conventional steering system. Therefore, this paper proposes a control algorithm to create the force feedback torque for SBW system. The direct current measurement approach is used to estimate torque at the steering wheel and front axle motor as elements to the feedback torque, while, adding the compensation torque for a realistic feedback torque. The gain scheduling with a linear quadratic regulator controller is used to control the feedback torque and to vary a steering feel gain. To investigate the effectiveness of the proposed algorithm, a real-time hardware in the loop (HIL) methodology is developed using Matlab XPC target toolbox. The results show that the proposed algorithm is able to generate the feedback torque similar to EPS steering system. Furthermore, the compensation torque is able to improve the steering feel and stabilize the system.


Author(s):  
Xin Guan ◽  
Yu-Ning Zhang ◽  
Chun-Guang Duan ◽  
Wen-Liang Yong ◽  
Ping-Ping Lu

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.


Author(s):  
Olga Mikhaylovna Tikhonova ◽  
Alexander Fedorovich Rezchikov ◽  
Vladimir Andreevich Ivashchenko ◽  
Vadim Alekseevich Kushnikov

The paper presents the system of predicting the indicators of accreditation of technical universities based on J. Forrester mechanism of system dynamics. According to analysis of cause-and-effect relationships between selected variables of the system (indicators of accreditation of the university) there was built the oriented graph. The complex of mathematical models developed to control the quality of training engineers in Russian higher educational institutions is based on this graph. The article presents an algorithm for constructing a model using one of the simulated variables as an example. The model is a system of non-linear differential equations, the modelling characteristics of the educational process being determined according to the solution of this system. The proposed algorithm for calculating these indicators is based on the system dynamics model and the regression model. The mathematical model is constructed on the basis of the model of system dynamics, which is further tested for compliance with real data using the regression model. The regression model is built on the available statistical data accumulated during the period of the university's work. The proposed approach is aimed at solving complex problems of managing the educational process in universities. The structure of the proposed model repeats the structure of cause-effect relationships in the system, and also provides the person responsible for managing quality control with the ability to quickly and adequately assess the performance of the system.


2021 ◽  
Vol 9 (2) ◽  
pp. 118
Author(s):  
Xinqing Zhuang ◽  
Keliang Yan ◽  
Pan Gao ◽  
Yihua Liu

Anchor dragging is a major threat to the structural integrity of submarine pipelines. A mathematical model in which the mechanical model of chain and the bearing model of anchor were coupled together. Based on the associated flow rule, an incremental procedure was proposed to solve the spatial state of anchor until it reaches the ultimate embedding depth. With an indirect measurement method for the anchor trajectory, a model test system was established. The mathematical model was validated against some model tests, and the effects of two parameters were studied. It was found that both the ultimate embedding depth of a dragging anchor and the distance it takes to reach the ultimate depth increase with the shank-fluke pivot angle, but decrease as the undrained shear strength of clay increases. The proposed model is supposed to be useful for the embedding depth calculation and guiding the design of the pipeline burial depth.


Electronics ◽  
2021 ◽  
Vol 10 (15) ◽  
pp. 1843
Author(s):  
Jelena Vlaović ◽  
Snježana Rimac-Drlje ◽  
Drago Žagar

A standard called MPEG Dynamic Adaptive Streaming over HTTP (MPEG DASH) ensures the interoperability between different streaming services and the highest possible video quality in changing network conditions. The solutions described in the available literature that focus on video segmentation are mostly proprietary, use a high amount of computational power, lack the methodology, model notation, information needed for reproduction, or do not consider the spatial and temporal activity of video sequences. This paper presents a new model for selecting optimal parameters and number of representations for video encoding and segmentation, based on a measure of the spatial and temporal activity of the video content. The model was developed for the H.264 encoder, using Structural Similarity Index Measure (SSIM) objective metrics as well as Spatial Information (SI) and Temporal Information (TI) as measures of video spatial and temporal activity. The methodology that we used to develop the mathematical model is also presented in detail so that it can be applied to adapt the mathematical model to another type of an encoder or a set of encoding parameters. The efficiency of the segmentation made by the proposed model was tested using the Basic Adaptation algorithm (BAA) and Segment Aware Rate Adaptation (SARA) algorithm as well as two different network scenarios. In comparison to the segmentation available in the relevant literature, the segmentation based on the proposed model obtains better SSIM values in 92% of cases and subjective testing showed that it achieves better results in 83.3% of cases.


2016 ◽  
Vol 10 (10) ◽  
pp. 133
Author(s):  
Mohammad Ali Nasiri Khalili ◽  
Mostafa Kafaei Razavi ◽  
Morteza Kafaee Razavi

Items supplies planning of a logistic system is one of the major issue in operations research. In this article the aim is to determine how much of each item per month from each supplier logistics system requirements must be provided. To do this, a novel multi objective mixed integer programming mathematical model is offered for the first time. Since in logistics system, delivery on time is very important, the first objective is minimization of time in delivery on time costs (including lack and maintenance costs) and the cost of purchasing logistics system. The second objective function is minimization of the transportation supplier costs. Solving the mathematical model shows how to use the Multiple Objective Decision Making (MODM) can provide the ensuring policy and transportation logistics needed items. This model is solved with CPLEX and computational results show the effectiveness of the proposed model.


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