PositionSensor.cpp

00001 
00002 #include "mbed.h"
00003 #include "PositionSensor.h"
00004 #include "math_ops.h"
00005 //#include "offset_lut.h"
00006 //#include <math.h>
00007 
00008 PositionSensorAM5147::PositionSensorAM5147(int CPR, float offset, int ppairs){
00009     //_CPR = CPR;
00010     _CPR = CPR;
00011     _ppairs = ppairs;
00012     ElecOffset = offset;
00013     rotations = 0;
00014     spi = new SPI(PA_7, PA_6, PA_5);
00015     spi->format(16, 1);                                                          // mbed v>127 breaks 16-bit spi, so transaction is broken into 2 8-bit words
00016     spi->frequency(25000000);
00017     
00018     cs = new DigitalOut(PA_4);
00019     cs->write(1);
00020     readAngleCmd = 0xffff;   
00021     MechOffset = offset;
00022     modPosition = 0;
00023     oldModPosition = 0;
00024     oldVel = 0;
00025     raw = 0;
00026     flag_first_time = true;
00027     }
00028     
00029 void PositionSensorAM5147::Sample(float dt){
00030     GPIOA->ODR &= ~(1 << 4);
00031     raw = spi->write(readAngleCmd);
00032     raw &= 0x3FFF;                                                              //Extract last 14 bits
00033     GPIOA->ODR |= (1 << 4);
00034     int off_1 = offset_lut[raw>>7];
00035     int off_2 = offset_lut[((raw>>7)+1)%128];
00036     int off_interp = off_1 + ((off_2 - off_1)*(raw - ((raw>>7)<<7))>>7);        // Interpolate between lookup table entries
00037     int angle = raw + off_interp;                                               // Correct for nonlinearity with lookup table from calibration
00038 //    if(flag_first_time){
00039 //        old_counts = angle;
00040 //        flag_first_time = false;
00041 //        }
00042     if(angle - old_counts > _CPR/2){
00043         rotations -= 1;
00044         }
00045     else if (angle - old_counts < -_CPR/2){
00046         rotations += 1;
00047         }
00048     
00049     old_counts = angle;
00050     oldModPosition = modPosition;
00051     modPosition = ((2.0f*PI * ((float) angle))/ (float)_CPR);
00052     position = (2.0f*PI * ((float) angle+(_CPR*rotations)))/ (float)_CPR;
00053     MechPosition = position - MechOffset;
00054     float elec = ((2.0f*PI/(float)_CPR) * (float) ((_ppairs*angle)%_CPR)) + ElecOffset;
00055     if(elec < 0) elec += 2.0f*PI;
00056     else if(elec > 2.0f*PI) elec -= 2.0f*PI ; 
00057     ElecPosition = elec;
00058     
00059     float vel;
00060     //if(modPosition<.1f && oldModPosition>6.1f){
00061 
00062     if((modPosition-oldModPosition) < -3.0f){
00063         vel = (modPosition - oldModPosition + 2.0f*PI)/dt;
00064         }
00065     //else if(modPosition>6.1f && oldModPosition<0.1f){
00066     else if((modPosition - oldModPosition) > 3.0f){
00067         vel = (modPosition - oldModPosition - 2.0f*PI)/dt;
00068         }
00069     else{
00070         vel = (modPosition-oldModPosition)/dt;
00071     }    
00072     
00073     int n = 40;
00074     float sum = vel;
00075     for (int i = 1; i < (n); i++){
00076         velVec[n - i] = velVec[n-i-1];
00077         sum += velVec[n-i];
00078         }
00079     velVec[0] = vel;
00080     MechVelocity =  sum/((float)n);
00081     ElecVelocity = MechVelocity*_ppairs;
00082     ElecVelocityFilt = 0.99f*ElecVelocityFilt + 0.01f*ElecVelocity;
00083     }
00084 
00085 int PositionSensorAM5147::GetRawPosition(){
00086     return raw;
00087     }
00088 
00089 float PositionSensorAM5147::GetMechPositionFixed(){
00090     return MechPosition+MechOffset;
00091     }
00092     
00093 float PositionSensorAM5147::GetMechPosition(){
00094     return MechPosition;
00095     }
00096 
00097 float PositionSensorAM5147::GetElecPosition(){
00098     return ElecPosition;
00099     }
00100 
00101 float PositionSensorAM5147::GetElecVelocity(){
00102     return ElecVelocity;
00103     }
00104 
00105 float PositionSensorAM5147::GetMechVelocity(){
00106     return MechVelocity;
00107     }
00108 
00109 void PositionSensorAM5147::ZeroPosition(){
00110     rotations = 0;
00111     MechOffset = 0;
00112     //flag_first_time = true;
00113     Sample(.00025f);
00114     MechOffset = GetMechPosition();
00115     }
00116     
00117 void PositionSensorAM5147::SetElecOffset(float offset){
00118     ElecOffset = offset;
00119     }
00120 void PositionSensorAM5147::SetMechOffset(float offset){
00121     MechOffset = offset;
00122     }
00123 
00124 int PositionSensorAM5147::GetCPR(){
00125     return _CPR;
00126     }
00127 
00128 
00129 void PositionSensorAM5147::WriteLUT(int new_lut[128]){
00130     memcpy(offset_lut, new_lut, sizeof(offset_lut));
00131     }
00132     
00133 
00134 //
00135 //PositionSensorEncoder::PositionSensorEncoder(int CPR, float offset, int ppairs) {
00136 //    _ppairs = ppairs;
00137 //    _CPR = CPR;
00138 //    _offset = offset;
00139 //    MechPosition = 0;
00140 //    out_old = 0;
00141 //    oldVel = 0;
00142 //    raw = 0;
00143 //    
00144 //    // Enable clock for GPIOA
00145 //    __GPIOA_CLK_ENABLE(); //equivalent from hal_rcc.h
00146 // 
00147 //    GPIOA->MODER   |= GPIO_MODER_MODER6_1 | GPIO_MODER_MODER7_1 ;           //PA6 & PA7 as Alternate Function   /*!< GPIO port mode register,               Address offset: 0x00      */
00148 //    GPIOA->OTYPER  |= GPIO_OTYPER_OT_6 | GPIO_OTYPER_OT_7 ;                 //PA6 & PA7 as Inputs               /*!< GPIO port output type register,        Address offset: 0x04      */
00149 //    GPIOA->OSPEEDR |= GPIO_OSPEEDER_OSPEEDR6 | GPIO_OSPEEDER_OSPEEDR7 ;     //Low speed                         /*!< GPIO port output speed register,       Address offset: 0x08      */
00150 //    GPIOA->PUPDR   |= GPIO_PUPDR_PUPDR6_1 | GPIO_PUPDR_PUPDR7_1 ;           //Pull Down                         /*!< GPIO port pull-up/pull-down register,  Address offset: 0x0C      */
00151 //    GPIOA->AFR[0]  |= 0x22000000 ;                                          //AF02 for PA6 & PA7                /*!< GPIO alternate function registers,     Address offset: 0x20-0x24 */
00152 //    GPIOA->AFR[1]  |= 0x00000000 ;                                          //nibbles here refer to gpio8..15   /*!< GPIO alternate function registers,     Address offset: 0x20-0x24 */
00153 //   
00154 //    // configure TIM3 as Encoder input
00155 //    // Enable clock for TIM3
00156 //    __TIM3_CLK_ENABLE();
00157 // 
00158 //    TIM3->CR1   = 0x0001;                                                   // CEN(Counter ENable)='1'     < TIM control register 1
00159 //    TIM3->SMCR  = TIM_ENCODERMODE_TI12;                                     // SMS='011' (Encoder mode 3)  < TIM slave mode control register
00160 //    TIM3->CCMR1 = 0x1111;                                                   // CC1S='01' CC2S='01'         < TIM capture/compare mode register 1, maximum digital filtering
00161 //    TIM3->CCMR2 = 0x0000;                                                   //                             < TIM capture/compare mode register 2
00162 //    TIM3->CCER  = 0x0011;                                                   // CC1P CC2P                   < TIM capture/compare enable register
00163 //    TIM3->PSC   = 0x0000;                                                   // Prescaler = (0+1)           < TIM prescaler
00164 //    TIM3->ARR   = CPR;                                                      // IM auto-reload register
00165 //  
00166 //    TIM3->CNT = 0x000;  //reset the counter before we use it  
00167 //    
00168 //    // Extra Timer for velocity measurement
00169 //    
00170 //    __TIM2_CLK_ENABLE();
00171 //    TIM3->CR2 = 0x030;                                                      //MMS = 101
00172 //    
00173 //    TIM2->PSC = 0x03;
00174 //    //TIM2->CR2 |= TIM_CR2_TI1S;
00175 //    TIM2->SMCR = 0x24;                                                      //TS = 010 for ITR2, SMS = 100 (reset counter at edge)
00176 //    TIM2->CCMR1 = 0x3;                                                      // CC1S = 11, IC1 mapped on TRC
00177 //    
00178 //    //TIM2->CR2 |= TIM_CR2_TI1S;
00179 //    TIM2->CCER |= TIM_CCER_CC1P;
00180 //    //TIM2->CCER |= TIM_CCER_CC1NP;
00181 //    TIM2->CCER |= TIM_CCER_CC1E;
00182 //    
00183 //    
00184 //    TIM2->CR1 = 0x01;                                                       //CEN,  enable timer
00185 //    
00186 //    TIM3->CR1   = 0x01;                                                     // CEN
00187 //    ZPulse = new InterruptIn(PC_4);
00188 //    ZSense = new DigitalIn(PC_4);
00189 //    //ZPulse = new InterruptIn(PB_0);
00190 //    //ZSense = new DigitalIn(PB_0);
00191 //    ZPulse->enable_irq();
00192 //    ZPulse->rise(this, &PositionSensorEncoder::ZeroEncoderCount);
00193 //    //ZPulse->fall(this, &PositionSensorEncoder::ZeroEncoderCountDown);
00194 //    ZPulse->mode(PullDown);
00195 //    flag = 0;
00196 //
00197 //    
00198 //    //ZTest = new DigitalOut(PC_2);
00199 //    //ZTest->write(1);
00200 //    }
00201 //    
00202 //void PositionSensorEncoder::Sample(float dt){
00203 //    
00204 //    }
00205 //
00206 // 
00207 //float PositionSensorEncoder::GetMechPosition() {                            //returns rotor angle in radians.
00208 //    int raw = TIM3->CNT;
00209 //    float unsigned_mech = (6.28318530718f/(float)_CPR) * (float) ((raw)%_CPR);
00210 //    return (float) unsigned_mech;// + 6.28318530718f* (float) rotations;
00211 //}
00212 //
00213 //float PositionSensorEncoder::GetElecPosition() {                            //returns rotor electrical angle in radians.
00214 //    int raw = TIM3->CNT;
00215 //    float elec = ((6.28318530718f/(float)_CPR) * (float) ((_ppairs*raw)%_CPR)) - _offset;
00216 //    if(elec < 0) elec += 6.28318530718f;
00217 //    return elec;
00218 //}
00219 //
00220 //
00221 //    
00222 //float PositionSensorEncoder::GetMechVelocity(){
00223 //
00224 //    float out = 0;
00225 //    float rawPeriod = TIM2->CCR1; //Clock Ticks
00226 //    int currentTime = TIM2->CNT;
00227 //    if(currentTime > 2000000){rawPeriod = currentTime;}
00228 //    float  dir = -2.0f*(float)(((TIM3->CR1)>>4)&1)+1.0f;    // +/- 1
00229 //    float meas = dir*180000000.0f*(6.28318530718f/(float)_CPR)/rawPeriod; 
00230 //    if(isinf(meas)){ meas = 1;}
00231 //    out = meas;
00232 //    //if(meas == oldVel){
00233 //     //   out = .9f*out_old;
00234 //     //   }
00235 //    
00236 // 
00237 //    oldVel = meas;
00238 //    out_old = out;
00239 //    int n = 16;
00240 //    float sum = out;
00241 //    for (int i = 1; i < (n); i++){
00242 //        velVec[n - i] = velVec[n-i-1];
00243 //        sum += velVec[n-i];
00244 //        }
00245 //    velVec[0] = out;
00246 //    return sum/(float)n;
00247 //    }
00248 //    
00249 //float PositionSensorEncoder::GetElecVelocity(){
00250 //    return _ppairs*GetMechVelocity();
00251 //    }
00252 //    
00253 //void PositionSensorEncoder::ZeroEncoderCount(void){
00254 //    if (ZSense->read() == 1 & flag == 0){
00255 //        if (ZSense->read() == 1){
00256 //            GPIOC->ODR ^= (1 << 4);   
00257 //            TIM3->CNT = 0x000;
00258 //            //state = !state;
00259 //            //ZTest->write(state);
00260 //            GPIOC->ODR ^= (1 << 4);
00261 //            //flag = 1;
00262 //        }
00263 //        }
00264 //    }
00265 //
00266 //void PositionSensorEncoder::ZeroPosition(void){
00267 //    
00268 //    }
00269 //    
00270 //void PositionSensorEncoder::ZeroEncoderCountDown(void){
00271 //    if (ZSense->read() == 0){
00272 //        if (ZSense->read() == 0){
00273 //            GPIOC->ODR ^= (1 << 4);
00274 //            flag = 0;
00275 //            float dir = -2.0f*(float)(((TIM3->CR1)>>4)&1)+1.0f;
00276 //            if(dir != dir){
00277 //                dir = dir;
00278 //                rotations +=  dir;
00279 //                }
00280 //
00281 //            GPIOC->ODR ^= (1 << 4);
00282 //
00283 //        }
00284 //        }
00285 //    }
00286 //void PositionSensorEncoder::SetElecOffset(float offset){
00287 //    
00288 //    }
00289 //    
00290 //int PositionSensorEncoder::GetRawPosition(void){
00291 //    return 0;
00292 //    }
00293 //    
00294 //int PositionSensorEncoder::GetCPR(){
00295 //    return _CPR;
00296 //    }
00297 //    
00298 //
00299 //void PositionSensorEncoder::WriteLUT(int new_lut[128]){
00300 //    memcpy(offset_lut, new_lut, sizeof(offset_lut));
00301 //    }