EAGER: IIS (G&V):Scalable High-Fidelity Solids Simulation

摘要需要对物理模拟的基本算法进行基本的改变，以实现将物理模拟应用于资源受限的应用(例如实时游戏或外科训练)所需的性能数量级的提高。本研究对三个问题进行了研究：帧速率模拟、异步进化和多级解算器。帧速率模拟的方法包括通过仔细的能量管理原则来同时处理稳定性和衰减来确保稳定性。特别注意系统中的人工阻尼量，可以避免过度阻尼的模拟，这是一个限制现有技术可能的时间步长的问题。这种帧速率模拟器支持下一步：开发一种异步进化方案，该方案允许在高频运动区域中采取小的时间步长，并在其他地方采取大的时间步长。开发异步方案的其他尝试在采取大的时间步长时难以获得过大的衰减。这项研究正在研究一种围绕所提出的帧速率模拟器的异步方法，以缓解这一问题，因为阻尼量可以被显式控制。最后，为了减少单个时间步长的成本，我们正在使用多层方法来减少物理模拟中典型的大型线性系统的求解时间。多层次方法有很长的历史，但对于物理模拟社区来说，它们是新的。寻找合适的粗化和精化算子是多层方法的关键，虽然很难表达，但有可能在求解这些系统的收敛速度方面产生渐近改善。正在研究的方法代表了一种与当前技术截然不同的方法，这项探索性研究试图证明这一潜在变革性变化的可行性。

AbstractFundamental changes in the underlying algorithms of physical simulation are needed to bring about the orders of magnitude improvement in performance required to bring physical simulation to resource-constrained applications such as real-time games or surgical training. This research is investigating three issues: frame-rate simulation, asynchronous evolution, and multilevel solvers. The approach to frame-rate simulation consists of ensuring stability by careful energy management principles to address both stability and damping. Paying special attention to the amount of artificial damping in the system enables one to avoid excessively damped simulations, a problem that limits the time step size possible with existing techniques. Such a frame-rate simulator enables the next step: developing an asynchronous evolution scheme that allows small time steps to be taken in regions of high-frequency motion and large time steps to be taken elsewhere. Other attempts at developing asynchronous schemes have difficulty with excessive damping when taking large time-steps. This research is investigating an asynchronous method around the proposed frame-rate simulator in order to alleviate this problem, as the amount of damping can be explicitly controlled. Finally, to reduce the cost of a single time step, we are using multilevel methods to reduce the time spent solving large linear systems typical of physical simulation. Multilevel methods have a long history, but they are new to the physical simulation community. Finding suitable coarsening and refinement operators are key to multilevel methods and, although difficult to formulate, have the potential to create asymptotic improvements in the convergence rates of solving these systems. The methods being investigated represent a radically different approach from current techniques and this exploratory research is seeking to demonstrate the feasibility of this potentially transformative change.