Introduction to the National Key Laboratory of Complex Multibody System Dynamics

The National Key Laboratory of Complex Multibody System Dynamics is dedicated to addressing the critical demands for enhancing scientific, technological, and industrial research and development capabilities and equipment performance. It tackles major scientific and technological challenges in equipment multibody system dynamics and overcomes key technical bottlenecks, such as poor design performance, low manufacturing quality, high testing and evaluation costs, and operational safety risks, which have long constrained equipment development.

The Laboratory has led over 100 major engineering and research projects, both ongoing and completed, with outcomes applied to more than 150 major engineering applications worldwide. These achievements have been utilized in over 40 types of equipment, significantly improving performance, reducing testing costs, and ensuring operational safety. Several groundbreaking innovations have been achieved, including the Multibody System Transfer Matrix Method, internationally renowned as the Rui method, which marks a milestone in the history of scientific and technological development. The Laboratory has received eight National Science and Technology Progress Awards and National Technological Invention Awards. It serves as the host or affiliated institution for three international organizations: the International Society for Mechanical System Dynamics, the International Journal of Mechanical System Dynamics, and the standing International Conference on Mechanical System Dynamics.

The Laboratory has broken through a major global technical bottleneck that long restricted equipment development: computational speed cannot meet the requirements of system dynamics modeling and simulation. The theoretical and technical framework of the Rui method have been established. Further, a high-performance, large-scale industrial software for equipment based on the Rui method has been developed, achieving the fastest computational speed worldwide with intellectual property rights. It meets the urgent need for theories and platforms that can rapidly model and simulate the dynamics of equipment multibody systems, filling a gap in China.

This software is the only industrial software for multibody system dynamics of equipment in China. It encompasses a wide range of multibody dynamics models for various equipment, features advanced launch-dynamics functions, and is supported by a state-of-the-art database of equipment system dynamics. Its computational speed surpasses that of similar software. Moreover, the software supports cross-platform operation on Windows and Linux. It features automated equation derivation, automated visualization of post-processing, and stylized design of dynamic performance, enabling truly effective modeling and simulation of complex multibody dynamics of equipment. It has been successfully applied to the dynamics analysis and performance design of large-scale equipment in industries such as weapons, ships, astronautics, and aeronaoutics. The software enhances capabilities in the design, manufacturing, testing, evaluation, and utilization of equipment systems, including special-purpose vehicles, high-precision machine tools, and automobiles. The software has been applied to the simulation and design of various equipment, including vehicles, machine tools, aircraft, high-speed trains, robotics, construction machinery, special-purpose vehicles, and equipment manufacturing production lines, significantly improving equipment development capabilities and efficiency, shortening development cycles, and enhancing equipment performance.

The Laboratory has achieved substantial results in the research of magnetorheological (MR) fluids, MR damping devices, and MR control systems. It has developed nano-reinforced MR fluids with a wide operating temperature range, high yield stress, and high stability, as well as high-dynamic, fast-response MR variable stiffness and variable damping systems. These efforts have led to the establishment of a comprehensive technological framework for MR materials, devices, and control for vibration reduction in equipment. The technological outcomes have been validated or applied in six equipment types, achieving a reduction in typical equipment vibration by 30% to 80% or more, representing a world-leading level.

Core and critical technologies, including MR fluid preparation, MR device design theory and techniques, MR adaptive control technology, and system dynamics testing and evaluation methods, are fully self-controlled and protected by wholly owned intellectual property rights. These technological achievements have been verified or applied in six types of equipment, reducing vibration in typical equipment by 30% to over 80%, reaching an internationally leading level. The MR damping system delivers vibration reduction effects several times greater than passive damping, while significantly outperforming active damping systems in terms of power consumption, response speed, cost, and reliability. This technology can be applied to vibration control in a wide array of equipment, including vehicles, aircraft, high-speed trains, robotics, machine tools, construction machinery, and special-purpose vehicles, across industries such as automotive, structural engineering, defense, rail transportation, precision instrumentation, mechanical engineering, aerospace, and medical devices. Specific applications include suspension systems, seats, engines, cabs, and inertial measurement units, greatly enhancing equipment mobility, comfort, reliability, maneuverability, strength, and other key performance indicators.