Drowsy driver detection system
A method of detecting impairment of a driver of a vehicle. The method includes sensing, using a sensor, a position of the driver's head at a plurality of time points; determining, using a microprocessor, changes in the position of the driver's head between the plurality of time points; evaluating, using a microprocessor, whether the changes in the position of the driver's head between the plurality of time points exhibit at least one of a periodic and a quasi-periodic pattern; determining whether the driver is impaired based on the pattern of the changes in the position of the driver's head; and if the driver is impaired, alerting the driver using an alarm.
1. A method for monitoring the alertness of an operator of a vehicle, the method comprising:
using a sensor to detect a first plurality of positions of the operator's head relative to the sensor during a first period of time;
calculating a first set of head movement data using the first plurality of positions of the operator's head detected during the first period of time;
calculating a first power spectrum of the first set of head movement data;
using the sensor to detect a second plurality of positions of the operator's head relative to the sensor over a second period of time;
calculating a second set of head movement data using the second plurality of positions of the operator's head detected during the second period of time;
calculating a second power spectrum of the second set of head movement data;
comparing the second power spectrum to the first power spectrum to determine whether the second power spectrum has a greater magnitude than the first power spectrum at a characteristic frequency to evaluate the alertness of the operator;
using the sensor to detect a third plurality of positions of the operator's head relative to the sensor over a third period of time;
calculating a third set of head movement data using the third plurality of positions of the operator's head detected during the third period of time;
calculating a third power spectrum of the third set of head movement data; and
comparing the third power spectrum to the first power spectrum to determine whether the third power spectrum has a greater magnitude than the first power spectrum at a characteristic frequency to evaluate the alertness of the operator during the third period of time.
2. The method of claim 1 , wherein the sensor comprises an ultrasonic sensor.
3. The method of claim 1 , wherein the sensor is located behind the operator.
4. The method of claim 1 , wherein the sensor is located in front of the operator.
5. The method of claim 1 , wherein the head movement data comprises changes in the positions of the driver's head.
6. The method of claim 1 , further comprising alerting the operator when it is determined that the operator is impaired.
7. The method of claim 6 , wherein alerting the operator includes using at least one of an audible alarm and a visual alarm.
8. The method of claim 1 , wherein the operator is alert during the first period of time.
9. The method of claim 1 , wherein the alertness of the operator during the second period of time is unknown.
10. A system for monitoring the alertness of an operator of a vehicle, the system comprising:
at least one sensor for detecting the position of the operator's head relative to the sensor; and
a controller operatively coupled to the sensor, the controller configured to
use the sensor to detect a first plurality of positions of the operator's head relative to the sensor during a first period of time,
calculate a first set of head movement data using the first plurality of positions of the operator's head detected during the first period of time,
calculate a first power spectrum of the first set of head movement data;
use the sensor to detect a second plurality of positions of the operator's head relative to the sensor during a second period of time,
calculate a second set of head movement data using the second plurality of positions of the operator's head detected during the second period of time,
calculate a second power spectrum of the first set of head movement data,
compare the second power spectrum to the first power spectrum to determine whether the second power spectrum has a greater magnitude than the first power spectrum at a characteristic frequency to evaluate the alertness of the operator,
use the sensor to detect a third plurality of positions of the operator's head relative to the sensor over a third period of time,
calculate a third set of head movement data using the third plurality of positions of the operator's head detected during the third period of time,
calculate a third power spectrum of the third set of head movement data, and
compare the third power spectrum to the first power spectrum to determine whether the third power spectrum has a greater magnitude than the first power spectrum at a characteristic frequency to evaluate the alertness of the operator during the third period of time.
11. The system of claim 10 , wherein the sensor comprises an ultrasonic sensor.
12. The system of claim 10 , wherein the sensor is located behind the operator.
13. The system of claim 10 , wherein the sensor is located in front of the operator.
14. The system of claim 10 , wherein the head movement data comprises changes in the positions of the driver's head.
15. The system of claim 10 , wherein the controller is further configured to alert the operator when it is determined that the operator is impaired.
16. The system of claim 15 , wherein the controller alerts the operator using at least one of an audible alarm and a visual alarm.
17. The system of claim 10 , wherein the operator is alert during the first period of time.
18. The system of claim 10 , wherein the alertness of the operator during the second period of time is unknown.