| 摘要 |
Road gradient detection method for a vehicle under braking, steps include determination of base data (e.g. look-up table) relating tractive effort (e.g. engine torque / engine braking) to rate of change of speed on a flat road, continual sampling of tractive effort, acceleration, and braking effort (e.g. braking torque determined from anti-lock braking system), continual calculation of net effort dependent on live data / real time readings of tractive and braking efforts, and comparison of instant values for net effort and acceleration with corresponding base data values to determine instant surface gradient. The shift points for a multi-speed automatic transmission may be selected according to detected gradient, possibly chosen from a number of shift maps. Method may utilise a processor and read only memory. |
