PACCAR Inc
Real-time tracking and filtering of estimated driveline ratios

Abstract:

A computer system (e.g., an on-board vehicle computer system) creates or updates a mapping of transmission gears and respective driveline ratios during operation of the vehicle. The system obtains a current engine speed and vehicle speed and calculates a current driveline ratio for the vehicle based on the current engine speed and vehicle speed. If the driveline is engaged, the system updates the mapping based at least in part on the current driveline ratio. Performing the update may include adding a new transmission gear or updating an existing transmission gear in the mapping, or removing a duplicate transmission gear from the mapping. Applications include cruise control, predictive cruise control, predictive shifting, and selecting a gear for a specific purpose (e.g., for descending a hill).