论文标题
使用随机批处理方法进行指导问题的模型预测控制
Model predictive control with random batch methods for a guiding problem
论文作者
论文摘要
我们在排斥驱动因素的行动下模拟,模拟,模拟和控制一群逃避者的指导问题。该问题是在最佳控制框架中提出的,其中驾驶员(控制)旨在引导逃避者(状态)到欧几里得空间的所需区域。对于大量相互作用的药物而言,此类模型的数值模拟很快变得不可行。为了降低计算成本,我们使用随机批处理方法(RBM),该方法提供了动力学的计算可行近似。在每个时间步骤中,RBM将粒子集随机分为小亚集(批次),仅考虑每个批次内部的相互作用。由于平均效果,随着时间离散化的效果,RBM近似收敛到精确的动力学。我们提出了一种算法,该算法可以使用经典梯度下降来最佳控制固定的RBM近似轨迹。最终的控制对于原始完整系统不是最佳的,而是对减少的RBM模型的最佳选择。然后,我们采用模型预测控制(MPC)策略来处理动力学中的误差。当系统随着时间的推移而发展时,MPC策略包括定期更新状态并计算长期视野的最佳控制,该控制在较短的时间疗法中递归实现。这导致了半反馈控制策略。通过数值实验,我们表明RBM和MPC的组合可显着降低计算成本,从而保留控制整体动力学的能力。
We model, simulate and control the guiding problem for a herd of evaders under the action of repulsive drivers. The problem is formulated in an optimal control framework, where the drivers (controls) aim to guide the evaders (states) to a desired region of the Euclidean space. The numerical simulation of such models quickly becomes unfeasible for a large number of interacting agents. To reduce the computational cost, we use the Random Batch Method (RBM), which provides a computationally feasible approximation of the dynamics. At each time step, the RBM randomly divides the set of particles into small subsets (batches), considering only the interactions inside each batch. Due to the averaging effect, the RBM approximation converges to the exact dynamics as the time discretization gets finer. We propose an algorithm that leads to the optimal control of a fixed RBM approximated trajectory using a classical gradient descent. The resulting control is not optimal for the original complete system, but rather for the reduced RBM model. We then adopt a Model Predictive Control (MPC) strategy to handle the error in the dynamics. While the system evolves in time, the MPC strategy consists in periodically updating the state and computing the optimal control over a long-time horizon, which is implemented recursively in a shorter time-horizon. This leads to a semi-feedback control strategy. Through numerical experiments we show that the combination of RBM and MPC leads to a significant reduction of the computational cost, preserving the capacity of controlling the overall dynamics.