  We propose a map-aided vehicle localization method for GPS-denied
environments. This approach exploits prior knowledge of the road grade map and
vehicle on-board sensor measurements to accurately estimate the longitudinal
position of the vehicle. Real-time localization is crucial to systems that
utilize position-dependent information for planning and control. We validate
the effectiveness of the localization method on a hierarchical control system.
The higher level planner optimizes the vehicle velocity to minimize the energy
consumption for a given route by employing traffic condition and road grade
data. The lower level is a cruise control system that tracks the
position-dependent optimal reference velocity. Performance of the proposed
localization algorithm is evaluated using both simulations and experiments.
