Tracking of reference signals is addressed in the context of a class of nonlinear controlled systems modelled by r-th-order functional differential equations, encompassing inter alia systems with unknown “control direction” and dead-zone input effects. A control structure is developed which ensures that, for every member of the underlying system class and every admissible reference signal, the tracking error evolves in a prescribed funnel chosen to reflect transient and asymptotic accuracy objectives. Two fundamental properties underpin the system class: bounded-input bounded-output stable internal dynamics, and a high-gain property (an antecedent of which is the concept of sign-definite high-frequency gain in the context of linear systems).

在由r阶泛函微分方程建模的一类非线性控制系统的背景下解决了参考信号的跟踪问题，该系统尤其包括具有未知“控制方向”和死区输入效应的系统。开发了一种控制结构，可确保对于基础系统类的每个成员和每个允许的参考信号，跟踪误差都在规定的漏斗中发展，该漏斗选择为反映瞬态和渐近精度目标。系统类别有两个基本属性：有界输入，有界输出稳定的内部动力学和高增益属性（在线性系统中，其前身是符号确定的高频增益的概念）。