Understand Xiaomi Auto's 48V wire-controlled steering in one article: goodbye mechanical connection!

On November 14, Xiaomi Auto announced its intelligent chassis pre-research technologies, including Xiaomi fully active suspension, Xiaomi super four-motor system, Xiaomi 48V wire-controlled braking, and Xiaomi 48V wire-controlled steering.

Among them, Xiaomi's 48V wire-controlled steering technology can realize a steering wheel-free cockpit layout. Xiaomi officially explained the principles behind this technology today.

It is understood that the steering system is a key component of the vehicle. The traditional automobile steering system uses mechanical connections. When the driver turns the steering wheel, mechanical components such as the steering gear and steering column use the drive motor to assist in driving the wheels to swing and rotate, thereby reducing the driver's physical exertion when steering.

The Xiaomi 48V wire-controlled steering system eliminates the mechanical connection between the up-turn and down-turn, and the up-turn becomes a driver's hand force simulator. It also adopts a direct-drive motor solution, with only one motor completing the hand force simulation task, saving cabin space.

The solution accurately simulates the driver's feel by calculating the steering wheel's turning angle, actual vehicle speed and other information, making steering more flexible and smooth with almost no delay while driving.

Xiaomi said that the biggest advantage of the wire-controlled steering system is "human-machine decoupling", that is, the driver's operation and the vehicle's response are no longer restricted by mechanical components.

It is reported that the high-precision hand force simulator, equipped with advanced sensors and redundant electronic control units, can accurately capture the driver's steering intentions.

These signals are transmitted to the wheel-end steering actuator in real time and accurately. The latter drives the rack to move laterally through the motor, thereby accurately turning the wheel. The electrical signal becomes the "invisible bond" connecting the steering wheel and the wheel, breaking the constraints of the mechanical structure.

At the same time, the wire-controlled steering system also supports functions such as dynamically adjusting the steering ratio (ranging from 5:1 to 15:1) and setting the number of steering wheel circles.

The steering ratio is continuously adjustable, which means that when the vehicle is reversing or turning at low speed, the wheels can respond more sensitively to slight turns of the steering wheel.

When changing lanes at high speed, the wheels can maintain direction more stably, and the vehicle can autonomously switch between high-speed sports car mode and low-speed home mode.

It is reported that by using electronic signal connection, wire-controlled steering can provide two experiences: vibration isolation and comfortable driving in daily driving; real-time feedback of road feel and grasp of road surface information in dynamic driving.