Abstract:
The global emphasis on conserving energy resources has led to the adoption of hybrid power systems in
vehicles. Optimally applied, hybrid systems can save up to 40% on fuel costs. To optimally manage a hybrid
vehicle's energy flow it is necessary to know, in real time, all the energy requirements to complete a given
route. The energy consumption depends mainly on the vehicle mass, speed profile, and route topography. Of
these, the topographic profile is the one factor that is only route-dependent and not influenced by the vehicle
or driving styles. The heading vs. distance profile is also an example of a route characteristic not influenced
by the vehicle or driving style. In this study the topographic and heading profiles are used to identify routes,
and are easily measured by means of digital barometric pressure and compass sensors. Correlations between
the current route and previously travelled/stored routes are performed based on their topographic and
heading profiles in a point-by-point manner. Above-ground tests were first performed using a road vehicle
and six routes to evaluate the system. The system consistently and correctly identified a 20 km route within
the first 4 km. It also proved to function correctly in underground tests through the implementation of an
instrumented hand-held surveyor's wheel. This system finds direct practical application in optimizing the
energy management of an underground hybrid locomotive used by the mining industry in South Africa, but
can also be of benefit in applications where route identification is required and using GPS is not feasible.
