Alert systems and methods for a vehicle

1. A method, comprising:

determining at least one of interior conditions and exterior conditions of a vehicle that includes a plurality of haptic actuators disposed in a seat;

calculating at least one of a pulse width modulation (PWM) pattern and an on/off compensation pattern based on the determined at least one of the interior conditions and the exterior conditions, wherein calculating at least one of the patterns includes calculating the at least one of the patterns that generates haptic pulses with a high frequency component between about 40 Hz and about 80 Hz and a vertical acceleration of vibration normal to a bolster of the seat between about 50 m/s 2 and about 72 m/s 2 ; and

generating a signal with active periods that include at least one of the calculated patterns to command the plurality of haptic actuators to produce haptic pulses, and

wherein calculating the at least one of the PWM pattern and on/off compensation pattern is further based on an impact of the determined at least one of the interior conditions and the exterior conditions on a detectability of the haptic pulses to a driver.

2. The method of claim 1 wherein determining at least one of the conditions includes determining the interior conditions that include determining acoustics of the interior of the vehicle.

3. The method of claim 1 wherein determining at least one of the conditions includes determining the exterior conditions that include determining road vibration frequencies, and wherein calculating at least one of the patterns further includes calculating at least one of the patterns based on the road vibration frequencies.

4. The method of claim 3 wherein determining the road vibration frequencies includes determining whether an average magnitude of vibrations in a suspension system is above a threshold.

5. The method of claim 1 wherein calculating an on/off compensation pattern includes ceasing to command actuation of the haptic actuators when the haptic actuators exceed an upper threshold rotational speed, and includes resuming command of actuation of the haptic actuators when the rotational speed of the haptic actuators is less than a lower threshold.

6. The method of claim 1 wherein calculating at least one of the patterns includes calculating the at least one of the patterns that generates haptic pulses with a high frequency component between about 55 Hz to about 67 Hz.

7. The method of claim 1 further comprising calculating a taper for the active period to modify an acceleration profile of the haptic pulses, and wherein calculating at least one of the patterns includes calculating at least one of the patterns based on the taper.

8. A method, comprising:

determining at least one of interior conditions and exterior conditions of a vehicle that includes a plurality of haptic actuators disposed in a seat;

determining a high frequency component of haptic pulses to command from the haptic actuators based on the determined at least one of the interior conditions and the exterior conditions;

calculating at least one of a pulse width modulation (PWM) pattern and an on/off compensation pattern based on the at least one of the interior conditions and the exterior conditions to actuate the plurality of haptic actuators and generate haptic pulses with the high frequency component;

calculating a taper for an active period; and

generating a signal with active periods that include at least one of the calculated patterns to command the plurality of haptic actuators to produce the haptic pulses based at least in part on the taper.

9. The method of claim 8 further comprising determining road vibration frequencies, and wherein calculating at least one of the patterns further includes calculating at least one of the patterns based on the road vibration frequencies.

10. The method of claim 9 wherein determining the road vibration frequencies includes determining whether an average magnitude of vibration in a suspension system is above a threshold.

11. The method of claim 8 wherein determining the interior conditions includes determining acoustics of the interior of the vehicle that may impact a driver's ability to sense the haptic pulses.

12. The method of claim 8 wherein determining a high frequency component of haptic pulses to command further includes determining a high frequency component that is between about 55 Hz and about 67 Hz and a vertical acceleration of vibration normal to a bolster of the seat between about 50 m/s 2 and about 72 m/s 2 .

13. A vehicle, comprising:

a seat for supporting a driver of the vehicle;

a plurality of haptic actuators disposed in the seat and configured to produce haptic pulses; and

a controller that:

determines at least one of interior conditions and exterior conditions of the vehicle;

calculates at least one of a pulse width modulation (PWM) pattern and an on/off compensation pattern based on the at least one of the interior conditions and the exterior conditions;

calculate tapers for edges of active periods that include the at least one of the calculated patterns; and

generates a signal with the active periods to command the plurality of haptic actuators to produce the haptic pulses, and

wherein the controller calculates the at least one of the PWM pattern and on/off compensation pattern further based on the taper and on an impact of the determined at least one of the interior conditions and the exterior conditions on a detectability of the haptic pulses to a driver.

14. The vehicle of claim 13 wherein the controller further determines the interior conditions that include acoustics of the interior of the vehicle.

15. The vehicle of claim 14 further including a suspension system, and wherein the controller determines whether an average magnitude of vibration of the suspension system is above a threshold.

16. The vehicle of claim 13 wherein the controller calculates the at least one pattern that generates haptic pulses with a high frequency component between about 40 Hz and about 80 Hz and a vertical acceleration of vibration normal to a bolster of the seat between about 50 m/s 2 and about 72 m/s 2 .

17. The vehicle of claim 13 wherein the controller calculates the at least one pattern that generates haptic pulses with a high frequency component between about 55 Hz to about 67 Hz.