Dynamics simulation of large-scale multibody systems

接触在力学中具有核心重要性;它也是建模和仿真技术以及虚拟环境的许多应用中的关键要素。一个特别具有挑战性的问题是模拟大型铰接机械系统的操作，这些系统与其环境进行物理交互。这通常会导致在系统中的许多不同位置同时接触;同时还需要保持对系统元素之间的关节进行建模的双边约束。例如，开发用于大型起重机在船上和船外移动货物的虚拟环境，以及采矿业中通常使用的挖掘机。 我们具体计划解决这些问题的四个主要主题，分为三个工作包。第一个是使用接触问题的非线性优化算法的调查。我们特别着眼于分析避免摩擦锥离散化的可能性。工作的第二个主要内容将是研究模型划分和子结构，以确保有效的实施，这也可以实现实时性能。第三个主题是模拟弹性铰接链的刚体，其中一个重点是解决的问题，可以从改变段的数量和存在的高张力。第四部分是冗余约束构形的详细研究和相关仿真问题的解决。 我们希望这项工作的结果将产生重要的研究成果， 为加拿大经济做出贡献。模拟和虚拟环境行业在魁北克有着深厚的根基。预期成果将进一步加强这一工业部门，并将为新的商业机会奠定基础，有助于创造新的就业机会。这将对我们的合作伙伴CMLabs Simulations Inc.，以及Simwat和整个加拿大社会。研究培训将是这项工作的一项重要内容。

Contact is of central importance in mechanics; it is also the key element in many applications of modelling and simulation technologies, and virtual environments. A particularly challenging problem is the simulation of the operation of large articulated mechanical systems that come to physical interaction with their environment. This usually induces contact simultaneously at many different locations in the system; while the bilateral constraints that model the articulations among the system elements also need to be maintained. Examples include the development of virtual environments for operations of large cranes moving cargo in an out of ships, excavators generally employed in the mining industry. We specifically plan to address four main topics for these problems grouped in three work packages. The first is the investigation of the use of nonlinear optimization algorithms for contact problems. We particularly aim at the analysis of possibilities that avoid the discretization of the friction cone. The second main element of the work will be the study of model partitioning and substructuring to ensure efficient implementation, which can also achieve real-time performance. The third topic is the simulation of elastically articulated chains of rigid bodies, where a focus point is to tackle the problems that can from changing the number of segments and the presence of high tensile forces. The fourth element is the detailed study of redundant constraint configurations and the solution of related simulation problems. We expect that the results of the work will produce important research findings that will strongly contribute to the Canadian economy. The simulations and virtual environments industry has strong roots in Quebec. The expected results will further strengthen this industrial sector, and will generate the basis for new business opportunities and contribute to the creation of new jobs. This will be of significant benefit to our partners, CMLabs Simulations Inc., and Simwat and the Canadian society at large. Research training will be an important element of the work.