Yunnian System

The Yunnian System is an in-house developed, full-stack intelligent body control system (chassis domain control system) engineered by China's BYD Auto. Moving away from conventional setups where the suspension, body, and powertrain operate in isolated silos, the system achieves millisecond-level data coordination via a multi-dimensional sensor array and the Yunnian intelligent computing centre. This enables comprehensive active adjustment of vehicle dynamics across the longitudinal, lateral, and vertical axes. Tailored to different technical architectures and luxury positioning, the lineup comprises several variants: Yunnian-C (Intelligent Damping Body Control System), Yunnian-A (Intelligent Air Body Control System), Yunnian-P (Intelligent Hydraulic Body Control System), and the flagship Yunnian-X (Fully Active Body Control System), widely deployed across new energy rugged 4x4 off-roaders, executive sedans, and SUVs.

Core Technical Architecture and Control Logic

The technical architecture of the Yunnian System consists primarily of a comprehensive vehicle sensor matrix (cameras, LiDAR, and accelerometers), the central Yunnian intelligent computing centre, and dedicated actuators (adaptive damping shock absorbers, air springs, and hydraulic actuators): 

Multi-Level Active Adjustment and Multi-Dimensional Dynamic Coordination:

Depending on the variant, the Yunnian System delivers dynamic control ranging from damping fine-tuning to fully active vehicle lift. On Yunnian-A and Yunnian-P, for instance, the system actively adjusts air spring stiffness and ride height in real time (catering to extreme wading depths or high ground clearance demands), while stiffening the outer suspension during cornering to suppress body roll. The flagship Yunnian-X goes further with fully active electro-hydraulic and motor actuation, enabling smooth driving on three wheels, stationary "dancing" body movements, and peerless road bump isolation. 

New Energy Vehicle Chassis Integration and Preview Control: 

Leveraging BYD's core strengths in EV powertrain technology ("three-electric" systems) and vehicle electrical/electronic (E/E) architecture, the Yunnian System is deeply integrated into the powertrain, braking, and steering networks. Using forward-facing cameras and LiDAR to "preview" road conditions ahead, the system pre-emptively calculates and dials in optimal damper settings and body posture before the tyres hit potholes or speed humps, substantially enhancing ride comfort and chassis composure over uneven surfaces.

Safety Specifications and Physical Limitations

Driving at High Speeds or Extreme Off-Roading is Strictly Prohibited When Core Hydraulic/Pneumatic Lines Suffer Severe Leaks, Compressor/Accumulator Fails, or Critical Chassis Warning Lights are Illuminated (Prohibiting High-Speed or Off-Road Driving When Yunnian Systems Experience Pressure Leaks or Critical Faults): 

The Yunnian System relies heavily on a complex electro-mechanical-hydraulic high-pressure closed loop. Forcing the chassis to its limits with existing faults is strictly prohibited. If the system loses active adjustment and load-bearing support due to a malfunction, sudden high-speed lane changes or driving on unpaved roads can trigger severe, uncontrollable body roll or suspension collapse on one side. This causes an abrupt loss of tyre grip, posing an extreme risk of rollovers or severe collisions.

Continuing to Drive Based on Software Resets or Chance After Severe Undercarriage Scraping, Heavy Impacts, or Mechanical Linkage/Actuator Deformation is Strictly Prohibited (Prohibiting Continuing Driving After Severe Bottom Impacts Without Inspecting Suspension Actuators): 

The control arms, sensors, and hydraulic valve bodies of the Yunnian System are precision-engineered components subjected to immense mechanical stress. Physical damage to structural chassis parts must never be overlooked. Any sensor misalignment, bent suspension linkages, or cracked actuator housings resulting from severe bottoming-out will disrupt the Yunnian control logic entirely. The vehicle must undergo high-voltage isolation, mechanical inspection, and proper calibration at an authorised workshop before returning to the road.