The tens of billions blue ocean of wire-controlled chassis: smart driving "upward" and independent rise

Chassis, engine, and gearbox are the three core structural parts of traditional automobiles. Under the "new four modernizations" of automobiles, only the chassis has been retained, and "human-machine decoupling" has been achieved through wire-controlled transformation: the driver's operation commands It is transmitted to the actuator through the electronic controller, replacing traditional mechanical connections such as steering wheels, brakes, and pedals. Therefore, it has the advantages of high precision, high safety, and high response speed.

Structurally, the drive-by-wire chassis consists of five major systems: shift-by-wire, brake-by-wire, steering-by-wire, throttle-by-wire, and suspension-by-wire. The penetration rates of these five systems are 3%, <1%, and 100% respectively. , 25%, <3%, and the value of the bicycle is respectively 2,000~2,500 yuan, 5,000 yuan, 300 yuan, 400~500 yuan, and 10,000~20,000 yuan.

Obviously, as smart driving becomes the standard feature of mid-to-high-end models, the market focus of drive-by-wire chassis will also be concentrated on areas with high technical difficulty and high gold content such as steering, suspension, and braking.

Image source: Essence Securities Research Center

Gasgoo Automotive Research Institute predicts that in 2025, the domestic market size of automobile control-by-wire chassis will reach 60 billion yuan, with an average annual growth rate of 25.9%, of which the average annual growth rate of steering-by-wire and brake-by-wire will reach 72.2% respectively. and 45.3%.

The track attracts money, and new and old players naturally continue to emerge. Following Bosch, Continental, and ZF, Chinese independent brands are also continuing to make efforts in the two blue oceans of online braking and wire steering. At the Gasgoo 2022 Second Automotive Intelligent Chassis Conference, the IBS Division of Lianchuang Automotive Electronics Co., Ltd. General Manager Sui Qiaomei said:

Lianchuang Automotive Electronics has been in the field of wire-controlled chassis for decades. Its steering-by-wire and brake-by-wire products have all been mass-produced, with cumulative sales of more than 5 million and 2 million units respectively. It has the largest market share and market growth rate of independent brands in China. are at the forefront.

Sui Qiaomei | General Manager of IBS Division of Lianchuang Automotive Electronics Co., Ltd.

Sui Qiaomei emphasized that the development of intelligent chassis is an extremely urgent need, whether from the perspective of building a powerful automobile country or from the perspective of industrial development.

In terms of intelligent steering EPS and braking ABS/ESC systems, Lianchuang Automotive Electronics has successfully broken through the technology monopoly of international giants and achieved stable supply. So, how did Lianchuang Automotive Electronics start its independent technology layout in the field of wire control? ? And what opportunities will the development of drive-by-wire chassis bring to the scenario-based implementation of autonomous driving? Which areas of wire-controlled chassis will be the first to usher in a large-scale phase, and how will independent brands seize this opportunity?

Combined with the development history of Lianchuang Automotive Electronics, we may be able to get a glimpse of the answers to these questions.

From EPS to SBW, Lianchuang’s path to breakthrough in automotive core technology

Lianchuang Automotive Electronics Co., Ltd. was established in 2006. It is a core automotive electronic parts company under the leadership of SAIC. From the beginning, it focused on independent research and development of core automotive electronic technologies, including the core "stuck neck" technology in the steering field: Electric power steering (EPS) system.

"In 2008, the Shanghai World Expo was held. At that time, SAIC undertook a new energy vehicle task that required brushless EPS. At that time, the development of this area (in China) was still very weak. A foreign supplier said that it could do it, but it asked for 20 million euros in development costs.”

Driven by this opportunity, Lianchuang Automotive Electronics fully launched its self-research technology layout in the field of steering: "Lianchuang established an EPS core R&D team to carry out industry-university-research cooperation, independent innovation and research, and finally spent 20 million yuan to This system was built. "It helped SAIC successfully complete the task of using cars for the World Expo.

In 2012, Lianchuang Automotive Electronics launched the first-generation brushless electric steering system that was first produced in China and supplied in batches. Since then, Lianchuang has successively launched the second-generation integrated brushless/brushed electric steering system and the third-generation ASIL D-compliant electric steering system. The required modular electric steering system is the fourth generation fully redundant steering control system that meets L3 level intelligent driving.

Image source: Lianchuang Automotive Electronics

In fact, due to factors such as space limitations in the vehicle, signal transmission mechanism, response accuracy, response speed, etc., replacing the mechanical structure with a wire-controlled structure is a necessary condition to achieve multiple safety redundancies of the actuator.

Under normal circumstances, multiple independent and parallel control systems will work at the same time and share the total output demand. If one system fails, the remaining systems can independently provide remaining assistance, thereby avoiding the situation of complete helplessness. Multiple redundancy must be achieved , technical difficulties such as function synchronization and data sharing between different systems must be dealt with.

Mass production and being put on the road are the best proof of the technical confidence of a set of products.

On December 8, 2021, Xiangdao Robotaxi equipped with Lianchuang steer-by-wire was officially launched for operation. This is also the first practical application of steer-by-wire for a domestic independent brand.

Lianchuang's independent breakthrough in EPS technology has also given SAIC a say in the joint venture's business layout.

It is reported that around 2014, the foreign partner of a parts joint venture owned by SAIC originally wanted to build a wholly-owned EPS factory. However, because Lianchuang’s EPS products already had development capabilities, the foreign partner finally decided to cancel the wholly-owned company plan and instead cooperate with SAIC Lianchuang has increased cooperation and jointly established an EPS R&D center.

Steer-by-wire: the “execution” cornerstone of high-level autonomous driving

Sui Qiaomei revealed that in December 2025, Lianchuang Automotive Electronics will further launch the fifth-generation steer-by-wire (SBW) system that meets the full scenario application of L4 and above autonomous driving, including park autonomous vehicles, Robotaxi, and trunk heavy trucks. , moving towards a driverless future without a steering wheel.

On the steering-by-wire prototype vehicle jointly developed by Lianchuang, the steering wheel, human-computer interaction screen, and two-way control remote sensing can all control the direction of the vehicle to facilitate manual takeover. Among them, the interactive screen can also demonstrate the working status and key points of the steering-by-wire in real time. parameters, control the function switch of the steer-by-wire steering. This steer-by-wire prototype was put on the road for actual testing two years ago.

Image source: Lianchuang Automotive Electronics

Realizing physical decoupling between the steering wheel and the steering system is the core advantage of steer-by-wire. Its technical principle is: on the basis of electric power steering, the intermediate drive shaft between the steering wheel and the steering gear is eliminated, and the sensor is directly used. The steering wheel angle data is obtained and calculated by the ECU, and the steering is realized based on the vehicle speed and driving status.

Because commands are transmitted entirely through electrical signals, in theory, the steering-by-wire system can realize automated and unmanned steering operations through the debugging of software algorithms, combined with a road-sensing simulator and an electronically controlled steering column.

This will undoubtedly help high-end autonomous driving systems enter a new channel of "hands-off" operation.

According to the prediction of Gasgoo Automotive Research Institute, "EPS+ redundancy" will be used as a substitute for steer-by-wire in the short term to meet the needs of L3 and below autonomous driving. As the penetration rate of L3+ autonomous driving increases, steer-by-wire is expected to be applied in batches on high-end flagship models. The passenger car steer-by-wire market is expected to reach 4.4 billion yuan in 2025.

Focusing on the field of brake-by-wire, the localization of ESC breaks ground

In addition to steering-by-wire, Lianchuang’s precise efforts and rapid mass production in the field of online braking cannot be ignored.

Braking technology mainly consists of four parts: energy supply, control, transmission and brake. Braking by wire is essentially an electronic upgrade of the transmission device.

In the middle and late stages of the development of automotive mechanical technology, gas/liquid pressure braking has become the core solution for traditional automotive braking systems. Among them, air pressure brakes are mainly used in large commercial vehicles such as heavy trucks and trucks; while hydraulic brakes are mainly used in passenger cars. The core principle is: after the brake pedal is stepped on, the rear chamber of the vacuum booster is pushed to inhale air, and the The pressure difference pushes the brake master cylinder push rod forward, pushing the liquid in the brake master cylinder into the brake pipeline to form wheel braking force.