Passenger car steering pull and drift reduction considering suspension tolerances

<div class="section abstract"><div class="htmlview paragraph">The focus on driver and occupant safety as well as comfort is increasing rapidly while designing commercial vehicles in India. Improvements in the road network have enhanced road transport for commercial vehicles. Apart from the cost of operation and fuel economy, the commercial vehicles must deliver goods within stipulated time. These factors resulted in higher speed of operation for commercial vehicles. The design should not compromise the safety of the vehicle at these higher speeds of operation. The vehicle should obey the driver’s intended direction at all speeds and the response of the vehicle to driver input must be predictable without much larger surprises which can lead to accidents. The commercial vehicles are designed with rigid axle and RCB type steering system. This suspension and steering design combination introduce steering errors when vehicle travel over bump, braked and while cornering. The errors are well known as bump steer, brake steer and roll steer respectively and can cause the unintended vehicle directional response. This work shows the methodology to optimize the steering system design to reduce the steering errors at minimum level as well predictable in nature.</div><div class="htmlview paragraph">The methodology includes use of newly developed test rig to get the trace of draglink to steering arm ball joint under bump as well as braking conditions. The multibody dynamics model of steering-suspension assembly prepared in MSC ADAMS is validated with test rig results to rightly represent steering system kinematics and compliance. This validated model is then used with novel methodology to get steering hard points which will result in minimum steering errors that are easy for the driver to predict and control the vehicle during high-speed operations. The results obtained from this methodology is further validated with vehicle level result and it is found that this methodology helps to improve the accuracy of prediction for the dynamic behavior of vehicle during braking such as brake pull/steer.</div></div>

show abstract

Objective assessment of vehicle controllability in straight-line motion

Potashov

2022

Trudy NAMI

View full text Add to dashboard Cite

Introduction (statement of the problem and relevance). The problem of vehicle handling and stability during rectilinear motion was raised in the first half of the 20th century, and today this issue is still relevant. The requirements for handling, including during rectilinear movement of modern cars, are getting tougher. Straight-line stability and long-distance directional stability affect driver's fatigue, his driving safety and pleasure, as well as car fuel efficiency. Besides it, to provide modern driver assistance system, the car should possess good straight-line stability. At the same time, the design mustn't be affected by unbalanced forces and torques that could cause the trajectory deviation of the vehicle. There comes a need for an objective controllability and stability assessment of the car in a straight line.The purpose of the research was to analyze the existing methods for studying rectilinear motion controllability, to develop objective parameters for evaluating such motion, and to apply the worked out solutions when analyzing vehicle tests results.Methodology and research methods. Mathematical analysis, comparison, experiments, measurements were applied as research methods.Scientific novelty and results. The results have been presented in the form of a developed straight motion evaluation parameters list and were processed by calculating objective evaluation parameters. The scientific novelty is presented by the parameters of the driver's work objective assessment, and the first step has been made to correlate the objective and subjective assessment of the test driver.Practical significance. The developed method of the objective assessment can be applicable to all vehicles with traditional steering control.

show abstract

Passenger car steering pull and drift reduction considering suspension tolerances

Cited by 3 publications

References 13 publications

A Novel Lateral Dynamics Control Strategy of In-Wheel Motor Vehicle to Improve Agility and Straight-Line Driving Stability

A Novel Lateral Dynamics Control Strategy of In-Wheel Motor Vehicle to Improve Agility and Straight-Line Driving Stability

A Methodology of Optimizing Steering Geometry for Minimizing Steering Errors

Objective assessment of vehicle controllability in straight-line motion

Contact Info

Product

Resources

About