///<summary> A method for creating a Butterworth filter, based on the coefficents of the discrete filter, for filtering EMG data. </summary>
///<returns> N/A </returns>
void CreateEMGFilters()
{
int coefficients = 3;
List <double> B1 = new List <double>(coefficients);
List <double> A1 = new List <double>(coefficients);
B1.Add(Convert.ToSingle(0.956543225556877));
B1.Add(Convert.ToSingle(-1.91308645111375));
B1.Add(Convert.ToSingle(0.956543225556877));
A1.Add(Convert.ToSingle(1.000000000000000));
A1.Add(Convert.ToSingle(-1.91119706742607));
A1.Add(Convert.ToSingle(0.914975834801434));
//Create Butterworth High Pass filter for EMG data - 20Hz, order 2
emg_highpass_filter = new Butterworth(B1, A1);
coefficients = 3;
List <double> B2 = new List <double>(coefficients);
List <double> A2 = new List <double>(coefficients);
B2.Add(Convert.ToSingle(0.292893218813452));
B2.Add(Convert.ToSingle(0.585786437626905));
B2.Add(Convert.ToSingle(0.292893218813452));
A2.Add(Convert.ToSingle(1.000000000000000));
A2.Add(Convert.ToSingle(-2.22044604925031e-16));
A2.Add(Convert.ToSingle(0.171572875253810));
//Create Butterworth Low Pass filter for EMG data - 500Hz, order 2
emg_lowpass_filter = new Butterworth(B2, A2);
}
void CreateLinearEnvelopeFilter()
{
int coefficients = 5;
List <double> B = new List <double>(coefficients);
List <double> A = new List <double>(coefficients);
B.Add(Convert.ToSingle(7.69909892783804e-09));
B.Add(Convert.ToSingle(3.07963957113522e-08));
B.Add(Convert.ToSingle(4.61945935670283e-08));
B.Add(Convert.ToSingle(3.07963957113522e-08));
B.Add(Convert.ToSingle(7.69909892783804e-09));
A.Add(Convert.ToSingle(1.000000000000000));
A.Add(Convert.ToSingle(-3.95074409047721));
A.Add(Convert.ToSingle(5.85344171948211));
A.Add(Convert.ToSingle(-3.85463384437136));
A.Add(Convert.ToSingle(0.951936338552047));
linear_envelope_filter = new Butterworth(B, A);
}
///<summary> A method for creating a Butterworth filter, based on the coefficents of the discrete filter, for filtering angle data. </summary>
///<returns> N/A </returns>
void CreatePositionFilter()
{
//Create Butterworth Low Pass Filter for angle data - 6Hz, order 4
int coefficients = 5;
List <double> B = new List <double>(coefficients);
List <double> A = new List <double>(coefficients);
B.Add(Convert.ToSingle(7.69909892783804e-09));
B.Add(Convert.ToSingle(3.07963957113522e-08));
B.Add(Convert.ToSingle(4.61945935670283e-08));
B.Add(Convert.ToSingle(3.07963957113522e-08));
B.Add(Convert.ToSingle(7.69909892783804e-09));
A.Add(Convert.ToSingle(1.000000000000000));
A.Add(Convert.ToSingle(-3.95074409047721));
A.Add(Convert.ToSingle(5.85344171948211));
A.Add(Convert.ToSingle(-3.85463384437136));
A.Add(Convert.ToSingle(0.951936338552047));
position_filter = new Butterworth(B, A);
}