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Phase_Finder.h@0:adae25491b93, 2016-04-18 (annotated)
- Committer:
- mikeb
- Date:
- Mon Apr 18 01:14:36 2016 +0000
- Revision:
- 0:adae25491b93
- Child:
- 8:aaf5cde0aa0a
1st Draft. Some accuracy errors when close to sensor axis. ; Needs a filter and a method to process the 2 sensors. ; Filter is a must.
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| mikeb | 0:adae25491b93 | 1 | #include <mbed.h> |
| mikeb | 0:adae25491b93 | 2 | using namespace std; |
| mikeb | 0:adae25491b93 | 3 | const int SAMPLE_LENGTH = 251; |
| mikeb | 0:adae25491b93 | 4 | const int PEAKS = 4; |
| mikeb | 0:adae25491b93 | 5 | |
| mikeb | 0:adae25491b93 | 6 | /** A |
| mikeb | 0:adae25491b93 | 7 | * } |
| mikeb | 0:adae25491b93 | 8 | * } |
| mikeb | 0:adae25491b93 | 9 | * @endcode |
| mikeb | 0:adae25491b93 | 10 | */ |
| mikeb | 0:adae25491b93 | 11 | |
| mikeb | 0:adae25491b93 | 12 | class Phase_Finder { |
| mikeb | 0:adae25491b93 | 13 | |
| mikeb | 0:adae25491b93 | 14 | public: |
| mikeb | 0:adae25491b93 | 15 | /** Create a |
| mikeb | 0:adae25491b93 | 16 | * |
| mikeb | 0:adae25491b93 | 17 | * @param _pin mbed AnalogIn pin where the analog output of sensor is connected |
| mikeb | 0:adae25491b93 | 18 | * |
| mikeb | 0:adae25491b93 | 19 | * @note Supported types of sensors: |
| mikeb | 0:adae25491b93 | 20 | */ |
| mikeb | 0:adae25491b93 | 21 | Phase_Finder(int sampleRate, float frequency); |
| mikeb | 0:adae25491b93 | 22 | float estimate(float samples[], int leng); |
| mikeb | 0:adae25491b93 | 23 | |
| mikeb | 0:adae25491b93 | 24 | |
| mikeb | 0:adae25491b93 | 25 | private: |
| mikeb | 0:adae25491b93 | 26 | float est_Phase(); |
| mikeb | 0:adae25491b93 | 27 | void est_Max(float samples[]); |
| mikeb | 0:adae25491b93 | 28 | float wavelength; |
| mikeb | 0:adae25491b93 | 29 | float frequency; |
| mikeb | 0:adae25491b93 | 30 | int sampleRate; |
| mikeb | 0:adae25491b93 | 31 | int indices1[PEAKS]; |
| mikeb | 0:adae25491b93 | 32 | int length; |
| mikeb | 0:adae25491b93 | 33 | int peaks; |
| mikeb | 0:adae25491b93 | 34 | float phase; |
| mikeb | 0:adae25491b93 | 35 | |
| mikeb | 0:adae25491b93 | 36 | }; |
| mikeb | 0:adae25491b93 | 37 | Phase_Finder::Phase_Finder(int nsampleRate, float freq) : sampleRate(nsampleRate), frequency(freq) |
| mikeb | 0:adae25491b93 | 38 | { |
| mikeb | 0:adae25491b93 | 39 | //wavelength = (338.4/freq); |
| mikeb | 0:adae25491b93 | 40 | } |
| mikeb | 0:adae25491b93 | 41 | |
| mikeb | 0:adae25491b93 | 42 | void Phase_Finder::est_Max(float samples1[]) { |
| mikeb | 0:adae25491b93 | 43 | |
| mikeb | 0:adae25491b93 | 44 | |
| mikeb | 0:adae25491b93 | 45 | for (int j = 0; j<peaks; j++) { |
| mikeb | 0:adae25491b93 | 46 | float max = 0; |
| mikeb | 0:adae25491b93 | 47 | |
| mikeb | 0:adae25491b93 | 48 | for (int i = j*ceil(sampleRate/frequency); i< (j+1)*ceil(sampleRate/frequency); i++) { |
| mikeb | 0:adae25491b93 | 49 | if (max < samples1[i]) { |
| mikeb | 0:adae25491b93 | 50 | max = samples1[i]; |
| mikeb | 0:adae25491b93 | 51 | indices1[j] = i; |
| mikeb | 0:adae25491b93 | 52 | } |
| mikeb | 0:adae25491b93 | 53 | } |
| mikeb | 0:adae25491b93 | 54 | if (indices1[j] - ceil(sampleRate / frequency)/2 >= 0) { |
| mikeb | 0:adae25491b93 | 55 | for (int i = -ceil(sampleRate / frequency)/2; i< ceil(sampleRate/frequency) / 2; i++) { |
| mikeb | 0:adae25491b93 | 56 | samples1[indices1[j] + i] = 0; |
| mikeb | 0:adae25491b93 | 57 | } |
| mikeb | 0:adae25491b93 | 58 | } |
| mikeb | 0:adae25491b93 | 59 | else { |
| mikeb | 0:adae25491b93 | 60 | for (int i = 0; i< indices1[j] + ceil(sampleRate / frequency) / 2; i++) { |
| mikeb | 0:adae25491b93 | 61 | samples1[indices1[j] + i] = 0; |
| mikeb | 0:adae25491b93 | 62 | } |
| mikeb | 0:adae25491b93 | 63 | } |
| mikeb | 0:adae25491b93 | 64 | |
| mikeb | 0:adae25491b93 | 65 | } |
| mikeb | 0:adae25491b93 | 66 | } |
| mikeb | 0:adae25491b93 | 67 | |
| mikeb | 0:adae25491b93 | 68 | |
| mikeb | 0:adae25491b93 | 69 | float Phase_Finder::est_Phase() { |
| mikeb | 0:adae25491b93 | 70 | float avgDist = 0; |
| mikeb | 0:adae25491b93 | 71 | float ph; |
| mikeb | 0:adae25491b93 | 72 | for (int i = 0; i<peaks - 1; i++){ |
| mikeb | 0:adae25491b93 | 73 | avgDist += indices1[i] - ceil(sampleRate/frequency*i); |
| mikeb | 0:adae25491b93 | 74 | } |
| mikeb | 0:adae25491b93 | 75 | avgDist = avgDist / (peaks- 1); |
| mikeb | 0:adae25491b93 | 76 | ph = avgDist / float(sampleRate) * float(frequency) *float(360); |
| mikeb | 0:adae25491b93 | 77 | return ph; |
| mikeb | 0:adae25491b93 | 78 | } |
| mikeb | 0:adae25491b93 | 79 | |
| mikeb | 0:adae25491b93 | 80 | float Phase_Finder::estimate(float sampl[], int leng) { |
| mikeb | 0:adae25491b93 | 81 | length = leng; |
| mikeb | 0:adae25491b93 | 82 | peaks = floor(frequency / sampleRate*length); |
| mikeb | 0:adae25491b93 | 83 | est_Max(sampl); |
| mikeb | 0:adae25491b93 | 84 | return est_Phase(); |
| mikeb | 0:adae25491b93 | 85 | |
| mikeb | 0:adae25491b93 | 86 | } |