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Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
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OCR for page 66
HUMAN FACTORS IN THE DESIGN OF TACTICAL DISPLAY SYSTEMS FOR THE INDIVIDUAL SOLDIER: PHASE I
APPENDIX A Display System Features, Human Performance Considerations, and Research Issues
Control or Display Device
Sensory and Ergonomic Considerations
Benefits
Costs
Head/Helmet-Mounted Display
Always available
Does not have to be held in the hand or manipulated
Can easily be aligned on target or terrain feature
Wide field of view
Can be used to guide movement
Added information improves situation awareness of medium to long-range environment
Added weight on head
Off center CG
More complex and fragile than hand-held display
Precision/alignment requirements more severe
Wide field of view results in inadequate resolution
Display information content may overload or distract user, reducing situation awareness
Monocular Helmet-Mounted Display
Minimum weight
Simplest HMD; less alignment required
Eye with no display remains dark adapted
Eye with no display continues to sample real world
Severe visual rivalry problems, such as target suppression (involuntary) and “cognitive switching”
CG is off sideways as well as forward
Smallest FOV; least information capability; more and larger head movements required
No depth information
Difficulty to navigate on uneven terrain
Biocular Helmet-Mounted Display
Wider FOV, more information, easier to navigate
No interocular rivalry
Less complex to adjust than binocular
Heavier than monocular
Poor resolution
Incorrect depth information
Isolates user from environment
Binocular Helmet-Mounted Display
Can provide stereo viewing
Better depth information for mobility
Better target recognition
Heaviest optics
Alignment and adjustments more complex and critical
Helmet-Mounted Display with See–Through (Transparent Optics)
Display content can be integrated with the real world scene
Referenced navigational and targeting data can provide “where to look” guidance
User retains visual contact with the real world
Display collimation interferes with eye's accommodative response to the real world
Display luminance interferes with eye's luminance adaptation to the real world
Display content may obscure objects in the real world (clutter)
Unstable registration of display image on the real world may induce disorientation
OCR for page 67
HUMAN FACTORS IN THE DESIGN OF TACTICAL DISPLAY SYSTEMS FOR THE INDIVIDUAL SOLDIER: PHASE I
Research and Testing Issues
Effects of weight and CG of a selected set of Helmet-Mounted Display optics configurations upon mobility, agility, fatigue
Effects of improved helmet liners on display stability and comfort
Tradeoff analysis of adjustable vs preset or automatic controls in electronics, optics
Field–of–View, resolution, contrast requirements for object detection and recognition, mobility
Effects of display information on local situation awareness
Effects of binocular rivalry on object detection and recognition, mobility, fatigue, disorientation
Optimum information content for a small display
Effects of anomalous stereo, parallax information on object detection and recognition, motion judgment, mobility
Effects of larger FOV on optimizing information context
Effects of stereo vision on object detection and recognition, mobility
Assessment of precision and registration requirements
Determination of how display characteristics may interfere with perception of the real world (i.e., collimation, luminance, display content)
Analysis of display context and positioning to enhance perception of the real world through the display
Assess registration requirements
OCR for page 68
HUMAN FACTORS IN THE DESIGN OF TACTICAL DISPLAY SYSTEMS FOR THE INDIVIDUAL SOLDIER: PHASE I
Control or Display Device
Benefits
Costs
Helmet-Mounted Display without See–Through (World Occluded)
Less complex (lighter) optics
Minor misregistration with real world less noticeable
User is isolated from real world
Major misregistration with real world is less detectable and can result in serious positioning errors
Significant re–adaptation time to real world when display is removed
Helmet-Mounted Display with Integrated Symbology and Sensor Image
Much more information can be coded symbolically
Critical features (eg. targets, navigation way points, supply drops) can be localized and enhanced
Remote sensor and intelligence information can be integrated
Users must be trained to use symbology
Luminance, depth, and apparent size of symbology must be integrated with the sensor image and world
A tendency to load the user with more information than needed avoided
Unstable symbology can induce motion illusions, disorientation, loss of balance
Helmet-Mounted Display with Remote Sensor Image (e.g, Offset Sensor, Laser Sight on Weapon)
Information not locally available may be integrated
Weapons may be aimed without exposure
Movement with sensors not collocated with the eye can induce motion and position illusions resulting in errors, disorientation, motion sickness
Differences in scale, optical axis, resolution of multiple sources can induce error and confusion
Hand-Held Display (See Through as Telescope or Binoculars)
No added weight on head
Quick to align; user controls registration
Can be stored when not needed
Better mobility for running, taking cover
Must be unstowed to use
Fatiguing to use for sustained periods
Cabling could become unwieldy
Hand-Held Display (no See Through)
Light and simple
Can allocate higher resolution for maps, schematics
Very limited functionality
Must be stowed, hooked into gear, computer
Displays with Nonvisual Wavelength Sensor Images
Users can see at night and in poor visibility weather conditions
Nonvisual image characteristics (e.g., thermal signature) can add information for object I.D.
Sensors have resolution, contrast, color limitations whose effects on viewing must be trained
Added weight, complexity
User becomes dependent on systems that can fail
Nonvisual characteristic (e.g., thermal signature) can be misleading, and interpretation must be trained.
OCR for page 69
HUMAN FACTORS IN THE DESIGN OF TACTICAL DISPLAY SYSTEMS FOR THE INDIVIDUAL SOLDIER: PHASE I
Research and Testing Issues
Effects of display on local situation awareness
Effects of misregistration on mobility
Adaptation effects
Value added, optimum location, interference effect of each symbolically coded datum must be assessed in isolation, and in conjunction with other display content
Effects of misadjusted symbology luminance, depth, location in perception of the real world
Optimization of information content for specific tasks
Training requirements
Effects of unstable symbology on orientation, mobility
Assess requirements for integrating scale, resolution, optical axis of multiple images
Assess disorientation effects of remote sensor display
Assess ergonomic requirements for storage, deployment, cabling
Conduct performance tradeoff analysis versus same display content on an HMD
Assess ergonomic requirements
Evaluate functionality for maps, schematics, computer I/O
Assess available resolution and contrast in relation to specific task requirements
Evaluate enhanced information and mis–information potential of non–visual object recognition characteristics
Assess training requirements
OCR for page 70
HUMAN FACTORS IN THE DESIGN OF TACTICAL DISPLAY SYSTEMS FOR THE INDIVIDUAL SOLDIER: PHASE I
Control or Display Device
Benefits
Costs
Displays with Synthetic (Computer-Generated) Images from Map or Intelligence Data
Creative designers can provide the user with significantly improved information on own position, local environment (what is around the corner, where are the mines)
Creative designers can bury the user in useless information
Display resolution limits the amount of useful information that can be presented
Computer processing limitations (power-heat, weight) limit the sophistication to reduce/integrate useful information
Auditory Displays
Light weight
Always available
Does not interfere with vision or visual processing
Can be very time efficient
Does not hinder movement or manipulation of tools
Can isolate the user from the local environment if head phones are used
Added weight and complexity
Less suitable for complex information
Can interfere with processing of local auditory information and distract user
Severely affected by high local noise levels (i.e. loss or misinterpretation of message)
Tone Displays
Good for warning, cues
Meaning of signals must be trained
Limited set of tones can be recognized
Low information content
Speech
Complex information can be sent
Meaning is intrinsic
Message content is flexible
Can be time intensive
Vulnerable to masking, loss of data
Can distract user from an ongoing task
Controls (Local Display and Computer Equipment)
Allows user to select functions, modulate display, and system parameters
Added weight
Added complexity
Added training
Can distract user from correct task priority (e.g., attempts to communicate rather than fire)
Manual Controls (Buttons, Switches)
Familiar to users
Simple to operate
Can be made very rugged (e.g., membrane, capacitance switches)
Limited functionality can result in proliferation of controls to serve required needs (e.g., buttons on helicopter controls)
Conventional Computer Keyboard
Very flexible
Standardized I/O
Very complex
Fragile
Redundant functionality
Heavy and bulky
Programmable or Menu-Driven Control
Flexible
Compact
Can be made rugged
Can have high functionality with limited keyset
Efficient design of functions and control structure is difficult
Users must be well trained in operation
OCR for page 71
HUMAN FACTORS IN THE DESIGN OF TACTICAL DISPLAY SYSTEMS FOR THE INDIVIDUAL SOLDIER: PHASE I
Research and Testing Issues
Value added, optimum geometric design and location and interference effects of each information datum must be assessed in isolation and as integrated with other information on the display, in the context of specific task requirements
Assess training requirements
Assess effects on local situation awareness of headphones, bone conduction speakers
Assess effect of environmental noise upon message reception
Define optimum content and format of messages in the context of specific task requirements
Assuming a limited set of tones may be used, define task specific uses of warnings and cues and assess performance
Assess training requirements
Evaluate effects of incoming messages as distractors
Evaluate effect upon local situation awareness
Assess tendency to “tune out” messages (dependent upon perceived appropriateness and usefulness of messages)
Assess number of functions which require user control in the context of specific task requirements
Define and test minimum control sets
Assess need for full complexity
Assess ergonomics requirement
Define and test optimum control sets in the context of specific task requirements
Assess training requirements
Assess ergonomic considerations
Determine feedback requirements
OCR for page 72
HUMAN FACTORS IN THE DESIGN OF TACTICAL DISPLAY SYSTEMS FOR THE INDIVIDUAL SOLDIER: PHASE I
Control or Display Device
Benefits
Costs
Speech Control
Frees hands for other tasks
Natural communication
Suitable for discrete commands
Poor for analog control
Current technology is error prone
Vulnerable to environmental noise
May require user to speak at inappropriate times
OCR for page 73
HUMAN FACTORS IN THE DESIGN OF TACTICAL DISPLAY SYSTEMS FOR THE INDIVIDUAL SOLDIER: PHASE I
Research and Testing Issues
Define appropriate functions in terms of discrete versus analog control functions and test performance
Assess effect of environmental noise
Abbreviations: CG, center of gravity
I/O, input-output
FOV, field of view
OCR for page 74
HUMAN FACTORS IN THE DESIGN OF TACTICAL DISPLAY SYSTEMS FOR THE INDIVIDUAL SOLDIER: PHASE I
This page in the original is blank.
Representative terms from entire chapter:
situation awareness
