Vehicle steer-by-wire system based on planetary roller screw pair

Abstract

The invention relates to a vehicle steer-by-wire system based on a planetary roller screw pair. The system comprises a first mechanical movable connecting rod and a second mechanical movable connecting rod which are movably connected with the two sides of a base respectively, a propelling mechanism respectively connected with the two movable connecting rods, a main transmission mechanism connectedwith the propelling mechanism, and a guide mechanism connected with the main transmission mechanism. The guide mechanism is connected with the base, the main transmission mechanism is connected witha driving system, the propelling mechanism comprises a transverse pull rod and a planetary ball screw pair connected with the transverse pull rod, a planetary nut of the planetary ball screw pair is connected with the main transmission mechanism, and the propelling mechanism, the first mechanical movable connecting rod, the base, the second mechanical movable connecting rod, the main transmissionmechanism and the guide mechanism form a six-rod mechanism. Compared with like systems in the prior art, the system of the invention has the following advantages: the reliability is high, and the controllability, accuracy and comfort of the vehicle steering system are improved.

Description

Technical field [0001] The invention relates to the field of vehicle-by-wire steering, in particular to a vehicle-by-wire steering system based on a planetary roller screw pair. Background technique [0002] With the development of new energy vehicles and autonomous driving technology, vehicle steering systems emphasize more controllability, accuracy and comfort of steering. The steering system of the vehicle has gradually developed from EPS (Electric Power Steering, electric power steering system) to the direction of steer-by-wire. The main difference between steer-by-wire and EPS is that the mechanical connection between the steering wheel and the front wheel is cancelled, and the sensor is used to obtain the steering data of the steering wheel, and then the ECU (Electronic Control Unit, electronic control unit) converts it into a specific Driving force data, using a motor to push the steering gear to turn the front wheels. At the same time, the control unit will feel the cha...

AI Technical Summary

Problems solved by technology

Usually, the above two sets of hydraulic cylinders are powered by the same system. This steering mechanism is only suitable for manned wheeled vehicles due to low steering accuracy.

Also due to its disadvantages of low transmission efficiency, high energy consumption of hydraulic pump stations, large space occupation, and complex control pipelines, it is not suitable for new energy electric vehicles and automatic driving.

also, figure 1 Another important defect of the front axle steering mechanism is that during the action of the two sets of hydraulic systems, the output of the push (pull) force is synchronous, but the direction of action is inconsistent, which leads to the complexity of the control process of pushing out and pulling in. The integration of the system has brought great difficulties

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