The basic performance of steering system is to ensure that any conditions the vehicle when turning the steering wheel better handling and stability.
With the continuous development of automotive electronic technology and integrated automotive systems, automotive steering system from the traditional hydraulic power steering system (Hydraulic Power Steering System, HPS), electric hydraulic power steering system (Electronic Control Hydraulic Power Steering Systern, ECHPS) ,glue stick developed to gradually promote the application of electric hydraulic power steering system (Electro-Hydraulic Power Steering System, EHPS). In recent years,glue gun automotive by-wire steering system (Steer-ing-By-Wire, SBW) has become a hot research abroad. SBW is the X-By-Wire kind. X-By-Wire's full name is "mechanical and hydraulic backup system is not security-related fault-tolerant system." "X" means any security-related operations, including steering, braking, and so on.
1-wire steering system vehicle structure and basic principles.
1.1 The structure of automotive wire steering system.
Automotive wire steering system from the steering wheel assembly, steering assembly and the implementation of the main controller (ECU) of three main parts, and fail-safe system, power and other auxiliary system.
Steering wheel assembly including the steering wheel, steering wheel angle sensor, torque sensors, steering wheel, aligning torque motor. The main function of the steering wheel assembly is to the driver's steering intention (by measuring steering angle) into digital signals, and passed to the main controller; also accept the torque signal sent by the main controller, steering wheel aligning torque generated to provide road feel to the driver the appropriate information. To implementation, including front-wheel angle sensor assembly, steering the implementation of the motor, steering motor controller and the front wheel steering components and other components. Assembly functions to implementation is to accept the host controller commands, steering through the steering wheel rotates the motor controller, to achieve the driver's steering intention.
Main controller of the collected signal processing, vehicle movement state judge to force the steering wheel back to the motor and steering motor are sending commands to control the two motors work to ensure that all conditions have the ideal vehicle to respond to reduce the driver with the speed of change in steering characteristics of the compensation task, to reduce driver burden. At the same time the controller also can identify the driver's operating instructions to determine the current state of the driver's steering operation is reasonable. When the car driver in a non-steady state or send the wrong command, by wire steering system will operate screen driver error, and automatic stability control, making the car as quickly as possible back to the stable state.
Fail-wire steering system is an important module, which includes a series of monitoring and implementation of the algorithm, for different fault type and fault level to make the appropriate treatment, in order to maximize their normal driving the car. As an application, one of the most widely used means of transport, the car must first consider the safety factor, on the basis of all, and thus the automatic detection and automatic fault handling is the most important by-wire steering system component systems. It uses strict fault detection and processing logic, with greater improve vehicle safety performance.
Undertake power system controller, two motors and the implementation of electrical power other vehicle missions, of which only the front corner of the implementation of the maximum power the motor will have 500-800W, together with other electronic equipment on the car, the power of the burden has been quite heavy. Therefore, to ensure grid stability under heavy load, the power of the performance is very important.
Automotive wire steering system 1.2 Principle.
Vehicle steering system is to determine the active safety of the key assembly, the traditional mechanical system, steering system, steering car steering wheel movement is manipulated by the driver through the steering and a series of rods to the steering wheel passes achieved . Automotive by-wire steering system with steering wheel steering wheel removed the mechanical connection between the fully realized by the power shift from the traditional steering system limitations, not only free to design the force transfer characteristics of steering and steering can be designed the angular transmission characteristics to the vehicle steering characteristics for the design of infinite space, is a major innovation in automotive steering system.