Slides for a poster I presented in the 20th Encontro Português de Computação Gráfica, in Viana do Castelo, Portugal, October 2012.

1. An Intuitive Navigation System:
Augmented Reality on the Car Windshield
WALDIR PIMENTA
(WPIMENTA@DI.UMINHO.PT)
CENTRO DE CIÊNCIA E TECNOLOGIA DE COMPUTAÇÃO
UNIVERSIDADE DO MINHO

2. Context / Motivation
Most current navigation assistance systems (e.g. GPS
devices) are HDD (Head-Down Displays).
Problems with this approach:
✘ Driver has to look away from the road
✘ Reduced reflexes due to the context switch
We can do better:
✔ HUD (Head-Up Displays)
(superimpose virtual images directly in the driver's field of view)
✔ AR (Augmented Reality)
(seamlessly integrate virtual elements into the real world context)
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3. State of the art2Product Year Overlay HUD AR On-road
Regular GPS -- ✘ ✘ ✘ ✔
Blaupunkt TravelPilot 2008 ✔ ✘ ✘ ✔
Wikitude Drive 2009 ✔ ✘ ✔ ✔
SuperImaging+GM HUD 2009 ✔ ✔ ✔ ✘
BMW Head-Up Display 2011 ✔ ✔ ✘ ✔
MVS Virtual Cable 2011 ✔ ✔ ✔ ✘
Pioneer Cyber Navi 2012 ✔ ✔ ✔ ✘
Proposed system -- ✔ ✔ ✔ ✔
Wikitude Drive BMW Head-Up DisplayMVS Virtual Cable

4. Proposed system3Requirements Challenges Proposed solutions
In complex intersections,
precise positioning of the
virtual elements is crucial to
reduce decision errors and
delay.
GPS is not enough for this:
~15m accuracy.
Differential GPS (~10cm
accuracy) is not widespread
yet.
Enhanced positioning using
outer camera and structure
from motion (SfM) computer
vision algorithms.
Such precision then
requires correct motion
parallax to avoid
unalignment issues when
the driver moves their head.
Specialized sensors or
headgear would increase
the system's cost and
complexity.
Video-based head tracking
with infrared cameras.
Finally, the virtual elements
must be viewable while
looking at the road (without
shifting focus to the
windshield).
Stereo images could solve
this, but would require
replacing the windshield
with a more sophisticated
display.
Horizontal lines (instead of
continuous virtual path)
which can be fused due to
lack of vertical edges.

5. Proposed system3
Fig. 1: non-stereoscopic HUD with eyes focused/converged on the road.

6. Proposed system3
Fig. 2: eliminating vertical edges should enable unconverged binocular fusion.

7. Research questions
Do horizontal lines work to avoid stereoscopy?
Otherwise, enhanced windshields might be needed for
AR content.
Is computer vision enough for fine adjustment of the GPS?
Other components might be needed: accelerometers,
gyroscopes, compass, mechanical trackers, infrared
sensors, laser sensors...
What projection hardware is best for AR car navigation?
In terms of size, display quality, robustness to visibility
conditions, cost... (potential alternative: AR glasses).
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8. Thank you.