Displays and Man-Machine Interaction - Lecture 6

Introduction to Displays and Man-Machine Interaction in Avionic Systems

Overview

Displays and Man-Machine Interaction are critical components of avionic systems that relate to how pilots receive and respond to information presented during flight. The data from aircraft sensors is synthesized into visual formats to enhance safety and operational efficiency.

Instructors and References

Dr. Khosru Rahman, a highly qualified lecturer (CEng, FIMechE, CMath, CSci, FIMA, BEM) is affiliated with the Royal Academy of Engineering. He can be reached at khosru.rahman@baesystems.com or A.K.Rahman@greenwich.ac.uk. The course references include "Introduction to Avionic Systems" by R.P.G. Collinson, Third Edition.

1. Importance of Cockpit Display Systems

1.1 Functionality

Cockpit displays serve the purpose of visually presenting crucial data and information derived from various aircraft sensors. These displays are vital for the safe operation of aircraft, whether civil or military, providing various types of information:

  • Primary Flight Information: Essential data for basic flight operations.

  • Navigation Information: Updates and guidance for routing and trajectories.

  • Engine Data: Performance metrics and status of engines.

  • Airframe Data: Structural status and measures.

  • Warning Information: Alerts regarding system malfunctions or dangers.

In military aircraft, additional data is available, such as:

  • Infrared Imaging Sensors: Visual enhancements via thermal imaging.

  • Radar Data: Utilization of radar signals for tracking and navigation.

  • Tactical Mission Data: Strategic information pertaining to mission objectives.

  • Weapon Aiming: Tracking and targeting functionalities.

  • Threat Warnings: Alerts for potential external threats.

2. Information Processing and Management

2.1 Information Display

While pilots can process substantial amounts of information, effective display of information is critical. Displays must be organized for quick assimilation, eliminating unnecessary data to relieve the pilot's workload, especially during high-stress scenarios.

2.2 Developments in Display Technologies

Continuous advancements aim to enhance man-machine interaction (MMI). Key technologies include:

  • Head-Up Displays (HUDs): Enables pilots to see critical data while maintaining visual awareness of the flying environment.

  • Helmet Mounted Displays (HMDs): Allows for augmented reality overlays on pilot vision.

  • Multi-Function Displays (MFDs): Offers diverse operational information in a compact format.

  • Synthetic Imagery: Provides pictorial representations of navigation and flight data.

  • Knowledge-Based Systems: Utilizes AI to optimize display management.

  • Human Factors Integration: Involves specialists in design to address ergonomic concerns from the outset.

3. Pilot Control Interfaces

3.1 Control Mechanisms

Complementary to displays, pilots also require efficient control mechanisms to operate avionic systems. Developments in this area include:

  • Multi-Function Keyboards: Adaptable inputs for varied tasks.

  • Touch Panel Displays: Intuitive interactions for system controls.

  • Direct Voice Input: Increasingly used to operate systems hands-free.

  • Audio Warning Systems: Designed to alert pilots to critical situations.

  • Eye Trackers: Under evaluation for potential future data entry methods.

4. Specific Technologies in Use

4.1 Head-Up Displays (HUDs)

The advent of HUDs marks a significant evolution in pilot data presentation. Historic records show the first production HUDs operational in 1962 with the Buccaneer strike aircraft in the UK. Key benefits of HUDs include:

  • Head-Up Operation: Enables pilots to view essential data without diverting gaze from external conditions.

  • Enhanced Situational Awareness: Facilitates better awareness, crucial for maneuvers such as avoiding wind shear or traffic.

4.2 Use Cases in Civil Aviation

  • Automatic Landing Guidance: Assists pilots in low visibility conditions by providing actionable visual cues.

  • Taxiway Guidance Display: Aids navigation on the ground.

  • Enhanced Vision Systems: Integrates imagery from sensors for navigation and landing in poor visibility conditions.

4.3 HUD Configuration

The typical configuration of a HUD involves the following components:

  • Combiner Glass: High optical efficiency mirrors that relay important information to the pilot while allowing external visibility.

  • Display Symbology: Generated from aircraft systems; relayed through a Cathode Ray Tube (CRT), adjusted with lenses to appear at infinity to the pilot's eye.

  • Fold Mirror and Collimation: Together these components ensure compact design with clear image reflection.

4.4 Holographic HUDs

Modern advancements include wide Field of View (FOV) holographic HUDs which enhance the pilot's experience even further. These systems utilize advanced optics to minimize physical space occupation while maximizing the displayed information's clarity.

5. Helmet Mounted Systems

5.1 Helmet Mounted Sights (HMS)

HMS enables targeting via head movement; offering enhanced situational awareness in combat scenarios. By tracking head position, target coordinates can be calculated and relayed to missile systems for targeting.

5.2 Helmet Mounted Displays (HMD)

HMDs serve as mini HUDs, integrating various sensing data into the pilot's visual field. Challenges such as monocular rivalry, especially at night, arise when visual information displayed to one eye conflicts with the other eye's unaltered view, which can impact performance under low visibility conditions.