Patent attributes
Probe data is analyzed to derive Longitudinal Speed Profiles (LSPs) and an Optimal Longitudinal Speed Profile (18) for each road segment or link in a digital map network. The Longitudinal Speed Profiles (LSPs) profiles are calculated during defined time spans whereas the Optimal Longitudinal Speed Profile (18) is based on the LSP for the time span corresponding only to free flow traffic conditions. All of the LSPs can used to create a respective energy cost for each time span, or only the OLSP (18) can be used (or alternatively the RRDSL 16 or LRRDSL 17) to calculate an energy cost for the free flow conditions only. The energy cost can be used to predict the energy required by a vehicle to traverse the link. Navigation software can use the energy cost to plan the most energy efficient route between two locations in the digital map. Sensory signals can be activated if a driver strays from the Optimal Longitudinal Speed Profile (18) to achieve extremely high levels of energy efficiency.