Nonlinear Fault Detection for Hydraulic Systems

Abstract

Abstract. One of the most important areas in the robotics industry is the development of robots capable of working in hazardous environments. As humans cannot safely or cheaply work in these environments, providing a high level of robotic functionality is important. Our work in this area focuses on a fault detection method known as analytical redundancy, or AR. In this paper we discuss the application to a hydraulic servovalve system of our novel rigorous nonlinear AR technique. AR is a model-based state-space technique that is theoretically guaranteed to derive the maximum number of independent tests of the consistency of sensor data with the system model and past control inputs. Conventional linear AR is only valid for linear sampled data systems. However, our new nonlinear AR (NLAR) technique maintains traditional linear AR's mathematical guarantee to generate the maximum possible number of independent tests in the nonlinear domain. Thus NLAR allows us to gain the benefits of AR testing for nonlinear systems with both continuous and sampled data.

Fault Estimation and Fault-Tolerant Control for the Pump-Controlled Electrohydraulic System

“…In the EHS, internal leakage fault and sensor fault is specifically considered as one of the main reasons impairing working performance or even making the system unstable unless appropriate compensation strategies are taken. This problem has evoked much interest in exploring various topics to tackle this fault in recent times [35,36]. In [37][38][39][40], the authors constructed a method based on extended state observers (ESOs) to estimate uncertain nonlinearities, parametric uncertainties, and external disturbances.…”

Energetic Approach for Control Surface Disconnection Fault Detection in Hydraulic Aircraft Actuators

“…(Varga, 2011). Nonlinear analytical redundancy technique based fault detection and isolation methods for precisely known nonlinear hydraulic actuator model was derived in (Leuschen et al, 2003). Nonlinear observer based fault detection method using simplified first order actuator model was proposed in (Garcia et al, 2009).…”

Detection of overload generated faults in electro-hydrostatic actuators

“…Several fault detection algorithms were developed for these type of hydraulic actuators. The most popular approaches are based on Extended Kalman Filters or on nonlinear observers [9]- [13]. These observers can be applied in state estimation or parameter estimation approach, depending on the formulated fault detection problem.…”