Apparatus and method for power hop detection and mitigation
A method and system of detecting power hop of a vehicle involves generating signals, including a current signal and a previous signal, indicative of the current longitudinal acceleration of the vehicle, calculating the period and amplitude of the signals, determining if the combined period and amplitude of the current signal exceeds a first predetermined value, and determining whether the combined period and amplitude of the current signal exceeds a second predetermined value greater than the first predetermined value. The method may also involve determining if the amplitude of the current signal exceeds a predetermined percentage of the amplitude of the previous signal. Power hop is detected when the combined period and amplitude of the current signal exceeds the first predetermined value as well as the second predetermined value, and possibly also when the amplitude of the current signal exceeds the predetermined percentage of the amplitude of the previous signal.
1. A method of detecting power hop of a vehicle, comprising:
obtaining a plurality of successive signals indicative of a longitudinal acceleration of the vehicle, including a current signal and a preceding signal that precedes the current signal, the vehicle including an engine connected to an electronic control unit, the electronic control unit controlling engine torque produced by the engine;
calculating a period and an amplitude of the successive signals;
determining if a combination of the period and amplitude of each of the successive signals exceeds a first predetermined value;
determining if the combination of the period and amplitude of the current signal exceeds a second predetermined value that is greater than the first predetermined value;
determining existence of a power hop condition when both the combination of the period and amplitude of the current signal exceeds the first predetermined value, and the combination of the period and amplitude of the current signal exceeds the second predetermined value; and
reducing the engine torque of the engine through control by the electronic control unit when the power hop condition is determined to exist.
2. A method according to claim 1 , further comprising determining if the amplitude of the current signal exceeds a predetermined percentage of the amplitude of the preceding signal, and determining the existence of the power hop condition when the amplitude of the current signal exceeds the predetermined percentage of the amplitude of the preceding signal.
3. A method according to claim 2 , further comprising determining if the amplitude of the current signal exceeds the predetermined percentage of the amplitude of the preceding signal a predetermined number of times, the predetermined number of times being more than one.
4. A method according to claim 3 , wherein power hop is determined to exist when: i) the combination of the period and amplitude of the current signal exceeds the first predetermined value at least the predetermined number of times; ii) the amplitude of the current signal exceeds the predetermined percentage of the preceding signal at least the predetermined number of times; and iii) the combination of the period and amplitude of the current signal exceeds the second predetermined value.
5. A method according to claim 1 , wherein power hop is determined to exist when the combination of the period and amplitude of the current signal exceeds the first predetermined value and when the combination of the period and amplitude of the current signal exceeds the second predetermined value.
6. A method according to claim 2 , wherein power hop is determined not to exist when the combination of the period and amplitude of the current signal does not exceed the first predetermined value and when the amplitude of the current signal does not exceed the predetermined percentage of the amplitude of the preceding signal.
7. A method according to claim 1 , wherein power hop is determined not to exist when the combination of the period and amplitude of the current signal does not exceed the first predetermined value and when the amplitude of the current signal does not exceed the predetermined percentage of the amplitude of the preceding signal.