Research On Vehicle Steering Comfort Based On Perception Field Of Operating Forces

Vehicle steering comfort is related to the driving experience,safety and stability.The improvement of vehicle steering comfort has great significance to reduce the risk of traffic accident and fatigue damage.For driver,vehicle,and road environment relate to cach other,steering system features,drivers' individual differences,and characteristics of driving scene should be considered synthetically in vehicle steering comfort research.Concerning this issue,firstly,the theory of perception field of operating forces is presented.The common features that influencing the handling comfort of man-machine systems are mapping to the field structure to classified and analyzed.Then the model of perception field of operating forces is built for quantitative assessment of the handling comfort of man-machine systems.Secondly,the model of perception field of operating forces is applied to the vehicle steering case.The steering force feedback characteristic parameters is taken as basic measure indexes,and the driver and driving scene factors are integrated to assess the vehicle steering comfort quantitatively.On this basis,the optimal steering force feedback characteristic parameters corresponding to different subjects in specific vehicle and the road condition are researched by simulated lane change test.And driver 's arm movement and power characteristics during the process of comfortable steering are analyzed by the method of experimental measurement and virtual simulation.Finally,it provides theory and method guidance for vehicle steering comfort evaluation and optimization.The main contents and results are as follows:(1)The same characteristics,influence factors,and the influence law of different kinds of manipulations are analyzed.And the model of perception field of operating forces is built by focusing on the characteristics of man-machine contact force and human body movement and power.The model could be used as a universal measure method of handling comfort.(2)The characteristic of the steering force required during the process of vehicle steering,the vehicle movement responded to steering,and the driver's steering behavior features are analyzed as the principle of man-machine interaction of vehicle steering.Then,the model of perception field of operating forces is applied to vehicle steering instance to quantitatively evaluate the steering comfort.(3)Aiming at the requirement of the steering comfort evaluation test,the vehicle steering simulation and testing system is designed and developed.The steering wheel assembly of steer-by-wire system is the core institutions prototype of this system.It's layout can be freely adjusted.And it can synchronically simulate the steering force feedback and the visual driving scene.(4)20 male and 20 female subjects participate in the simulated lane change test.In the scene of a car changing lanes on a road with three lanes,the simplified optimal characteristic parameters of steering force feedback,i.e.the maximum torque feedback MA and the steering stiffness coefficient k,are measured by the subjects' subjective preference and objective performance.The results show that optimal MA and k both increase with the rise of vehicle speed.The optimal MA of male subjects is larger than that of female subjects obviously,yet the optimal k has no significant difference.(5)A male subject is selected to measure his arm movement data under the condition of the optimal steering force feedback corresponding to him.Then the main muscle forces of the subject' arm are analyzed with the aid of OpenSim software.The results can provide method reference for the vehicle steering comfort quantitative study with the characteristic indexes of human biomechanics.