This letter discusses the eco-driving problem, considering both electric and conventional powertrains, and presents a pathway to solving it numerically using an indirect collocation method. Despite the low-order system dynamics, the piecewise fuel/efficiency map, gear shifting, and real-world traffic/road situations bring system discontinuities/switchings and pure state constraints into the problem formulation, which make the problem highly nonlinear and nontrivial to solve. This letter introduces smooth approximations to convert the original problem to an unconstrained (and penalized) smooth boundary-value problem. This approach eliminates the discussion of the switching structure and leads to a lightweight Newton-method-based solution procedure.

中文翻译：

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用间接搭配法和光滑表示法解决生态驾驶问题

这封信讨论了考虑电动和常规动力总成的环保驾驶问题，并提出了一种使用间接配置方法以数值方式解决这一问题的途径。尽管存在低阶系统动力学，但分段燃油/效率图，变速和现实交通/道路情况仍将系统的不连续性/切换和纯状态约束带入问题的表述，这使问题高度非线性且难以解决。这封信介绍了平滑近似，可将原始问题转换为无约束（且受罚）的平滑边值问题。这种方法消除了对交换结构的讨论，并导致了基于牛顿法的轻量级解决方案过程。