Abstract

This paper deals with the attitude estimation of a rigid body equipped with angular velocity sensors and reference vector sensors. A quaternion-based nonlinear observer is proposed in order to fuse all information sources and to obtain an accurate estimation of the attitude. It is shown that the observer error dynamics can be separated into two passive subsystems connected in “feedback”. Then, this property is used to show that the error dynamics is input-to-state stable when the measurement disturbance is seen as an input and the error as the state. These results allow one to affirm that the observer is “robustly stable”. The proposed observer is evaluated in real-time with the design and implementation of an Attitude and Heading Reference System (AHRS) based on low-cost MEMS (Micro-Electro-Mechanical Systems) Inertial Measure Unit (IMU) and magnetic sensors and a 16-bit microcontroller. The resulting estimates are compared with a high precision motion system to demonstrate its performance.

Highlights

  • The attitude information is obtained from inertial and magnetic sensors, namely, three rate gyros, three accelerometers and three magnetometers, orthogonally mounted, such that the sensor frame axes coincide with the principal axes of the rigid body

  • The estimation methodology proposed in this work is implemented and evaluated in real time, in order to assess its effectiveness

  • Special attention was paid to the low power consumption requirements and weight, leading to the selection of the digital signal controller (DSC), dsPIC33FJ128MC802, which was used with a clock speed of

Read more

Summary

A Robust Nonlinear Observer for Real-Time Attitude Estimation

José Fermi Guerrero-Castellanos 1, *, Heberto Madrigal-Sastre 1 , Sylvain Durand 2 , Lizeth Torres 3 and German Ardul Muñoz-Hernández 1. Received: 7 September 2013; in revised form: 22 October 2013 / Accepted: 22 October 2013 /

Motivations and Background
Contributions
Unit Quaternions and Attitude Kinematics
Angular Velocity Sensors
Reference Vector Sensors
Problem Statement
Attitude Estimation from Vector Observations
Nonlinear Attitude Observer with Bias Estimation
Passivity Interpretation of the Attitude Nonlinear Observer
Experimental Results
Conclusions
A Nonlinear Observer for Rigid Body Attitude
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call