Research On Active Steering System With Power Steering Ability

The active steering system with power stering ability is a new kind of steeringsystem. The motor can provid extra force and motion for the driver by a force andmotion synthesis mechanism to realize the system’s power steering ability and activesteering ability. The synthesis mechanism is composed by a double planetary wheelmechanism, and is integrated in the steering shaft. A jaw electromagnetic cluth is usedas an assist mechanism to change the working state of the steering system. It can makethe steering system realize power steering ability when the vehicle runs at a low speed,and realize active steering ability at other speed. So this steering system can make upthe limiations of the single power steering system or the single active steering systemon improveing the vehicle steering performance; it can also overcome the mutualinfluence of the power steering and active steering ability when simply integrates thepower steering system and the active steering system in one same car; All componentsof the steering system are linked by mechanical connetion, its reliability is much betterthan the steering-by-wire system. So the steering system introduced in this paper hasgreat significance for the improvement of the vehicle steering performance.Based on the special vehicle and characteristic of the steering system, this paperanalyzed and compared some force and motion synthesis mechanisms that werecommonly used, and selected the double planetary wheel mechanism which have apublic sun gear as the synthesis mechanism; And selected the jaw electromagneticcluth as the assist mechanism, basing on the analysis and comparation of theperformances and charastics of some electromagnetic cluths; and then designed thedouble planetary wheel mechanism, the worm gears connecting the double planetarywheel mechanism and the motor, and the jaw electromagnetic cluth. This paper alsoanalyzed the dynamic principles of the system power steering ability, active steeringability, and steering ability when the system breaks out. And establishsed the dynamicmodels of the steering system, designed the assist characteristic and the revising principle of the steering ratio, establishsed the simulation models, and do somesimulation tests using these simulation models. The simulation results show thesteering system this article introduced can effectively improve the vehicle’s steeringportability, steering sensitivity, and handing stability.