System and method for determining effective road grade characteristic

摘要

A vehicle system includes a computer in a vehicle, and the computer includes a processor and a memory. The computer is configured to determine an operational state of a vehicle, calculate a road grade value from data from a first sensor, calculate an effective road grade value from a torque demand value, update modeling variables to map the road grade value substantially to the effective grade value when the operation state is determined to be a steady-state condition, and calculate a road grade characteristic with the road grade value and the modeling variables.

主权项

1. A system comprising a computer in a vehicle, the computer comprising a processor and a memory, wherein the computer is configured to:
determine an operational state of a vehicle; calculate a road grade value from data from an accelerometer; calculate an effective grade value from a torque demand value; determine a correction coefficient to adjust the road grade value to substantially match the effective grade value when the operation state is determined to be a steady-state condition; determine a corrected effective grade based at least in part on the correction coefficient and the road grade value; and adjust a velocity of the vehicle with a cruise control system based at least in part on the corrected effective grade when the operation state is a transient condition; wherein the correction coefficient is based at least in part on the road grade value and the effective grade value.