# A Review of Coordinated Control Technology for Chassis of Distributed Drive Electric Vehicles
###### Abstract
The longitudinal subsystem (involving drive and braking) is primarily responsible for regulating the vehicle's acceleration and deceleration dynamic responses, directly affecting its acceleration performance, energy efficiency, and pitch dynamics [14; 15]. The lateral subsystem mainly undertakes path tracking and heading maintenance tasks, crucial for the vehicle's handling stability and transient response characteristics [16; 17]. The vertical subsystem is dedicated to the control of body attitude and attenuation of vibrations, directly influencing ride comfort, ride smoothness, and tires' road holding capability [18; 19]. As the mutual coupling and constraints between the control objectives of various subsystems become increasingly significant, achieving effective coordination and unified control among different subsystems has become a critical technical challenge. Especially in complex control scenarios characterized by a high dynamics, multiple variables, and strong coupling, how to efficiently perform torque distribution among the drive wheels and achieve coordinated scheduling among executive systems like drive, braking, steering, and suspension has become a core scientific problem and technical bottleneck faced by current research in distributed-drive chassis systems [20]. If coordinated control strategies are improperly designed or absent, not only will it be impossible to fully unleash the inherent potential of the distributed-drive architecture, but it may also lead to conflicts between actuators and imbalances in kinematic/dynamic coupling, consequently causing a deterioration in the overall vehicle performance and a reduction in control robustness. For this reason, coordinated chassis control technology for DDEVs has emerged. This technology aims to achieve a synergistic improvement in overall vehicle dynamic performance, energy efficiency, and driving safety. It accomplishes this by systematically coordinating and optimizing control tasks across multiple degrees of freedom--longitudinal (drive/braking), lateral (steering), and vertical (suspension)--and their corresponding actuators, such as in-wheel motors, Active Front Steering (AFS), and Active/Semi-Active Suspension Systems (ASS/SAS). This technology is not only a key technological support for enhancing the intelligence level of electric vehicles but also lays a solid foundation for deep integration and collaborative operation with high-level autonomous driving systems [21]. Coordinated chassis control technology is crucial for the advancement of next-generation, high-performance DDEVs. In view of its significance, this paper aims to systematically collate and critique pivotal recent research in this domain. Our review is structured as follows. First, we dissect and contrast the features and suitability of various coordinated control frameworks for DDEVs. Second, we detail recent breakthroughs in two-dimensional coordinated control, including lateral-longitudinal, lateral-vertical, and longitudinal-vertical motions. We then extend this analysis to comprehensive three-dimensional (lateral-longitudinal-vertical) integration. For each paradigm, we cover the primary control objectives, significant technological hurdles, prevalent algorithms, and essential torque/force distribution methods. By conducting a thorough examination of the merits, drawbacks, and potential applications of current coordinated control strategies, this review seeks to identify the critical unresolved scientific questions and technological bottlenecks in contemporary research and to project future developmental trajectories concerning intelligitization, integration, adaptability to diverse scenarios, and a profound synergy with advanced autonomous driving systems, thereby offering valuable references and inspiration for both academic scholars and engineering practitioners in this discipline.