APPLICATION OF WIRELESS SENSOR NETWORKS TO AIRCRAFT CONTROL AND HEALTH MANAGEMENT SYSTEMS

PRESENTATION TOPIC

Aamir Sohail 12063122-025

Iqtadar Ali Gilani 12063122-073

GROUP MEMBERS

The first step towards fly-by-wireless control systems is likely to be the introduction of wireless sensor networks (WSNs).

A typical commercial/military aircraft consists:

1: Safety-critical systems, such as aircraft engine control system, aircraft flight control systems

2: Non safety critical systems, such as structural and engine health monitoring systems, aircraft cabin environmental control system, inflight entertainment system, etc.

INTRODUCTION

Current systems based on wired connections:

1. Complex

2. Difficult to route

3. Heavy and prone to damage

The Airbus A380 for instance has:

4. 300 miles of cables

5. 98,000 wires

6. 40,000 connectors

CONTI……

So with Replacement of the current wire harness-based sensors with (WSN) we can achieve: Reduce the aircraft system weight. Increasing the number of sensors. Improved fuel efficiency and reduced carbon emissions. Reduction in direct costs.

In a recent study, that the use of a WSN can results: 90 lbs. weight reduction of Cessna 310R control systems. Increases its range by around 10%.

CONTI…..

TYPICAL SENSOR LOACTIONS OF COMMERCIAL AIRCRAFT

WSNs consists:Cluster of intelligent sensors designed to monitor physical parameters vibration, temperature, strain, pressure, etc.

Each sensor node within the network performs the function like sensing, data processing and wireless data transmission.

Use of microelectromechanical systems (MEMS) technology enables:

production of low-cost, low-power multifunctional sensorshaving very small size and light weight.

APPLICATIONS OF WSNs FOR AIR CRAFT SYSTEMS

The present aircraft engine control systems are based on a centralized architecture known as (FADEC).

Heavily shielded analog wire harnesses are used b/w sensor/actuator nodes and FADEC.

Which imparts a heavy weight penalty and high maintenance cost.

Before implementing WSN for AEC an intermediate step is distributed control architecture.

In distributed engine control (DEC), the functions of FADEC are distributed at the component level.

Each sensor/actuator is replaced by a smart sensor/actuator.

Distributed Aircraft Engine Control

These smart modules include local processing capability to allow and diagnostics and health management functionality.

DEC allows the implementation of advanced engine control technologies:

Active clearance control, active stall and surge control, active combustion control.

Which will improve aerothermodynamic efficiency, lower emissions and also help to reduce the control system weight.

Initially, WSN can be used only for the redundant sensors of DEC systems. An ideal DEC architecture, which will make use of the advantages of WSN, will have actuators with wired connections in order to provide a secure reliable control system architecture.

CONTI……..

An aircraft engine is a complex system requiring regular maintenance to ensure flight safety. Engine maintenance, repair and overhaul (MRO) operations are time consuming and costly.

Hence, in order to improve the time-on-wing of aircraft engines, it is desired to perform condition-based maintenance, which uses real-time data to schedule maintenance.

Use of WSN for aircraft engine health monitoring will enable implementation of condition-based monitoring algorithms due to availability of real-time data.

Each of the sensor nodes of the WSN will communicate with an on board diagnostics and health monitoring system, which willstore the data points for the entire flight.

Once on ground, this data will be transmitted to the maintenance workshopthrough wireless communication.

This will allow the use of online as well as offline diagnostic algorithms.

WSN FOR AIRCRAFT ENGINE HEALTH MANAGEMENT

The aircraft flight control systems consists:1: Flight control surfaces 2: cockpit controls 3: sensors and communication linkages b/w 1 & 2 actautors.Although the use of fly-by-wire(FBW) reduces the weight but system is still bulkier.Intelligent flight control systems (IFCS) are being developed to safely control the aircraft in the presence of structural damage.Increasing the number of sensors, without a substantial increase inweight is possible only by implementation of WSN. WSN will enable integration of several systems into one. The use of WSN for both aircraft engine control and aircraft flight control will allow integration between flight control and propulsion control, which can significantly improve performance of military aircrafts as well as UAVs.

FLY-BY-WIRELESS AIRCRAFT FLIGHT CONTROL SYSTEMS

One of the other advantage of using fly-by-wireless flight control systems based on WSN is :

If the pilots or flight deck controls become inoperable or incapacitated, ground-based air traffic control (ATC) or adjacent military aircraft with necessaryelectronics, can control the aircraft.

CONTI………

The increasing use of composite materials for aircraft structures, it is necessary to develop novel methods for aircraft structural health monitoring.

Most of the failures of the laminated composite structures originate withdelamination of layers, and for metal aircraft structures, cracks are developed in metal structures which grow over time leading to failures.

For both of these cases, visual inspection is not a reliable method for failure detection. This calls for a vibration analysis-based failure detection method.

WSN can be embedded into the composite structure which will harvest the vibration energy and will transmit the real-time data to the central health monitoring unit.

These sensors will be used to monitor the internal parameters like cracks, strain as well as external parameters like temperature, load, etc.

WSN FOR AIRCRAFT STRUCTURAL HEALTH MONITORING

Aircraft Hydraulic Monitoring Systems: These systems play a very important role in powering primary and secondary

flight control systems as well as several other like wheel brakes, cargo doors, loading ramps, etc.

By replacing the conventional sensors by WSN, it will be possible not only to display the signals to the gages in cockpit, but also to the ground servicing personnel for conducting on-wing aircraft engine maintenance.

Environmental Control Systems: (ECS) provide air supply with optimum humidity and sufficient oxygen

concentration to the passengers and crew and are also used for thermal control of the avionics, fuel and hydraulic systems.

Use of WSN for ECS will help to increase their reliability as well to improve the efficiency of the aircraft engines.

OTHER NON SAFETY CRITICAL SYSTEMS

LARGE COMMERCIAL AIRCRAFT HYDRAULIC SYSTEM

Emergency systems:Use of WSN for smoke and fire detection systems, emergency lighting systems, passenger address systems, etc.

Can help to reduce the weight and wiring complexity of these systems along with increasing their reliability.

CONTI………

Research needs to be conducted in the area of information fusion of wireless sensor networks for aircraft systems.

Energy harvesting methods needs further improvementin the terms of efficiency and reliability.

Development of high temperature electronics will enable the use of WSN for aircraft engine control and healthmonitoring.

A dedicated global spectrum for WSN for aircraft applications needs to be developed.

New wireless aircraft certification regulations needs tobe developed to address the various security and safetythreats.

Future Enhancements