The innovative new solution
aims to help GPS navigation differentiate between multilevel roads to correct
an error that engineers have tried to solve the last 20 years.
Present vehicle navigation systems that use
GPS with positioning error of 10-30 meters have had a long existing problem in
determining which road level a vehicle has entered, especially for flyovers
parallel to the ground level.
This error, which has plagued most GPS
systems during its 20-year history, is particularly prevalent in cities with multilevel
road networks such as flyovers and overpasses that run adjacent to ground level
roads. GPS navigation systems do not recognise that the vehicle has entered the
wrong level and continues to provide directions as if it were on the ground
level, and often takes too long to automatically correct this error.
Dubbed the Angle Difference Method, it will
measure and compare the inclination angle of a vehicle and angles of different
road levels stored in a Transport GIS to determine whether a vehicle has
entered the ramp of a flyover or still on the ground level.
Devised by Professor Anthony Yeh Gar-On’s
research team at the Department of Urban Planning and Design of the University
of Hong Kong (HKU), the method uses an ordinary smartphone, that can be put
anywhere at any angle in the vehicle, coupled with a plugged in or installed
onboard diagnostic (OBD) device.
“The invention provides an innovative,
simple, and inexpensive method to overcome the long existing vehicle navigation
problem that many people have tried to solve since GPS’s conception over 20
years ago. The new method allows for us to instantly determine whether a
vehicle has entered a flyover or still on the ground level. The research team
will further apply this Angle Difference Method to the navigation of autonomous
cars,” he explained.
The innovation by Professor Yeh and his
team, which won a gold medal award in April 2018 at the Geneva International
Exhibition of Inventions, boasts a 100% accuracy rate in identifying when the
vehicle has entered the wrong road level.
has received an US patent and an International PCT patent and generated several
academic papers published in international academic journals including IEEE Transactions on Intelligent
The HKU research team lead by Professor Yeh team
is currently in discussion with global GIS and vehicle navigation operators
including major operators in China on potential application of the system to
enable a major advancement in the current navigation system for vehicles,
particularly in large cities with complicated flyover networks.