This paper considers the problem of simultaneous estimation of the attitude, position and linear velocity for vehicles navigating in a three-dimensional space. We propose two types of hybrid nonlinear observers using continuous angular velocity and linear acceleration measurements as well as intermittent landmark position measurements. The first type relies on a fixed-gain design approach based on an infinite-dimensional optimization, while the second one relies on a variable-gain design approach based on a continuous–discrete Riccati equation. For each case, we provide two different observers with and without the estimation of the gravity vector. The proposed observers are shown to be exponentially stable with a large domain of attraction. Simulation and experimental results are presented to illustrate the performance of the proposed observers.

本文考虑了同时估计在三维空间中航行的车辆的姿态，位置和线速度的问题。我们提出了两种类型的混合非线性观测器，它们使用连续角速度和线性加速度测量以及间歇性地标位置测量。第一种依赖于基于无限维优化的固定增益设计方法，而第二种依赖于基于连续离散Riccati方程的可变增益设计方法。对于每种情况，我们都提供了两个不同的观察者，带有和不带有重力矢量的估计。拟议的观察者显示出具有大的吸引力域，它是指数稳定的。仿真和实验结果被提出来说明所提出的观察者的性能。