Optimal Secondary Controls
Using a Configurable Haptic
Interface
William Durfee
Department of Mechanical Engineering
University of Minnesota
Supported by
Center for Transportation Studies
Contributing players
Senthil S., Rahul Akolkar
The problem
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Automobile dashboards
getting crowded
Drivers do more while
driving
Distractions on the rise
The solution
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Replace many controls with single
control
Control takes on visual, haptic, auditory
characteristics tailored to task
Properties change with task
All without confusing the driver
Project tasks
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Design, fabricate, test configurable
panel control that uses visual, aural,
haptic feedback to aid user in task
performance
Determine how information bandwidth
depends on haptic, aural properties
Conduct human factors test in a driving
simulator
Is it the iDrive?
Virtual product prototyping
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Apply virtual reality technology to create product prototypes
Move beyond CAD-based visual rendering
See
Hear
Touch
?
?
Panel controls: simplified
paradigm for research
•Fixed in space, single d-o-f, low-force, simple graphics
•Sufficiently complex to enable exploration of research questions
Apparatus
to SGI
camera
haptic display
visual display
motion, force, torque motor
PC
SGI
speaker
servoamp
aural display
Ethernet
green
screen
Perceptual experiments
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Impact of display “quality” on
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Perceived level of realism
Ability of user to perform specified design
tasks
Understand sensory interaction in multimodel virtual environments

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Which sense dominates
Can you trick the sensory system…to your
advantage?
Probing experiments
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Compare virtual to real materials
Sight/sound/touch
With or without sensory conflict
speakers
green screen
motor
test material
TV itor
n
mo
probe
reference materials
camera
subject
to SGI
What we learned
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Virtual environment does well when
emulating soft materials
Haptic cues are important for matching
Adding visual or sound cues to haptics
improves perceived quality of match
Subjects tended not to use sound cues
for matching
Human motor performance
with visual/haptic interface
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What should haptic knob feel like for a selection
task?
Vary target haptics, background haptics
Best haptics for rapid selection: target damping
With good haptics, can perform secondary tasks
rapidly leaving more time for primary navigation
task
Technology development tasks
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Networked architecture for three control
computers (visual/haptic/aural)
New control technology
(visual/haptic/aural)
Technology
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Haptics
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Aural
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Matlab xPC Target for real-time control
Synthetic sound
Summation of decaying sinusoids
DirectSound for synchronized, real-time sound
production
Visual
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Windows based tools for visual effects
NVIDIA GeForce FX 5600
System Architecture
network
VISUAL PC
MATLAB
Visual C++
[Graphics scene,
Chromakey, UDP
communication]
UDP/IP
HAPTIC
PC
UDP/IP
AURAL
PC
xPC TARGET
VIDEO
CARD
SERVOAMP
SPEAKERS
MOTOR
TV
HUMAN
CAMERA
KNOB
DirectShow
*DirectShow System Overview: www.microsoft.com
Virtual Scene + Chromakeyed
User hand
Pro/E 
Open Inventor 
Direct3D X
Capture video for
chromakey:
DirectShow tools
Graphic knob rotates
using data via UDP from
haptics controller
STISIM Driving Simulator