Methods, systems, and apparatus for a drowsiness detection system that alerts the user to potentially drowsiness. The drowsiness detection system includes a sensor configured to detect a heart rate of a user. The drowsiness detection system includes an indicator configured to alert the user before the user becomes drowsy and a processor that is connected to the sensor and the indicator. The processor is configured to obtain the heart rate of the user and measure the heart rate of the user. The processor is configured to calculate at least one of a heart rate variability or a heart rate interval of the user based on the measured heart rate. The processor is configured to determine that the at least one of the heart rate variability or the heart rate interval of the user indicates that the user is becoming drowsy and activate the indicator to alert the user before the user becomes drowsy.