Evaluation of Bus Vibration Comfort Based on Passenger Crowdsourcing Mode

Algorithm 1

Filtering algorithm. () The parameter of alpha is calculated by equation: , where is single sampling time of filter and dT is sampling frequency. () The array of values is used to store the values of raw acceleration along -axis, -axis, and -axis, respectively. () The array of gravity is the values of gravity. () The array of linear_acceleration is acceleration without gravity.

(1) public void onSensorChanged(SensorEvent event)

(2)   final float alpha = 0.8;

(3)   gravity[0] = alpha gravity[0] + (1 − alpha) event.values[0];

(4)   gravity[1] = alpha gravity[1] + (1 − alpha) event.values[1];

(5)   gravity[2] = alpha gravity[2] + (1 − alpha) event.values[2];

(6)   linear_acceleration[0] = event.values[0] − gravity[0];

(7)   linear_acceleration[1] = event.values[1] − gravity[1];

(8)   linear_acceleration[2] = event.values[2] − gravity[2];

(9)