Ben Katz / HKC_MiniCheetah

Mini Cheetah Actuator Branch Superseded by: https://github.com/bgkatz/motorcontrol

Dependencies:   mbed-dev-f303 FastPWM3

Superseded by: https://github.com/bgkatz/motorcontrol

FOC/foc.cpp@31:61eb6ae28215, 2017-08-30 (annotated)

Committer:
benkatz
Date:
Wed Aug 30 15:28:40 2017 +0000
Revision:
31:61eb6ae28215
Parent:
29:0dbc822dd29a
Child:
32:ccac5da77844
Fixed performance bug

Who changed what in which revision?

UserRevisionLine numberNew contents of line
benkatz 24:58c2d7571207 1 #include "user_config.h"
benkatz 27:501fee691e0e 2 #include "hw_config.h"
benkatz 22:60276ba87ac6 3 #include "foc.h"
benkatz 22:60276ba87ac6 4
benkatz 26:2b865c00d7e9 5 #include "FastMath.h"
benkatz 26:2b865c00d7e9 6 using namespace FastMath;
benkatz 22:60276ba87ac6 7
benkatz 22:60276ba87ac6 8
benkatz 22:60276ba87ac6 9 void abc( float theta, float d, float q, float *a, float *b, float *c){
benkatz 25:f5741040c4bb 10 /// Inverse DQ0 Transform ///
benkatz 22:60276ba87ac6 11 ///Phase current amplitude = lengh of dq vector///
benkatz 22:60276ba87ac6 12 ///i.e. iq = 1, id = 0, peak phase current of 1///
benkatz 22:60276ba87ac6 13
benkatz 26:2b865c00d7e9 14 *a = d*cosf(theta) - q*sinf(theta);
benkatz 26:2b865c00d7e9 15 *b = d*cosf(theta - (2.0f*PI/3.0f)) - q*sinf(theta - (2.0f*PI/3.0f));
benkatz 26:2b865c00d7e9 16 *c = d*cosf(theta + (2.0f*PI/3.0f)) - q*sinf(theta +(2.0f*PI/3.0f));
benkatz 22:60276ba87ac6 17 }
benkatz 22:60276ba87ac6 18
benkatz 26:2b865c00d7e9 19
benkatz 22:60276ba87ac6 20 void dq0(float theta, float a, float b, float c, float *d, float *q){
benkatz 25:f5741040c4bb 21 /// DQ0 Transform ///
benkatz 22:60276ba87ac6 22 ///Phase current amplitude = lengh of dq vector///
benkatz 22:60276ba87ac6 23 ///i.e. iq = 1, id = 0, peak phase current of 1///
benkatz 22:60276ba87ac6 24
benkatz 26:2b865c00d7e9 25 //float cos = cosf(theta);
benkatz 26:2b865c00d7e9 26 //float sin = sinf(theta);
benkatz 26:2b865c00d7e9 27
benkatz 26:2b865c00d7e9 28 *d = (2.0f/3.0f)*(a*cosf(theta) + b*cosf(theta - (2.0f*PI/3.0f)) + c*cosf(theta + (2.0f*PI/3.0f)));
benkatz 26:2b865c00d7e9 29 *q = (2.0f/3.0f)*(-a*sinf(theta) - b*sinf(theta - (2.0f*PI/3.0f)) - c*sinf(theta + (2.0f*PI/3.0f)));
benkatz 22:60276ba87ac6 30 }
benkatz 22:60276ba87ac6 31
benkatz 22:60276ba87ac6 32 void svm(float v_bus, float u, float v, float w, float *dtc_u, float *dtc_v, float *dtc_w){
benkatz 25:f5741040c4bb 33 /// Space Vector Modulation ///
benkatz 25:f5741040c4bb 34 /// u,v,w amplitude = v_bus for full modulation depth ///
benkatz 22:60276ba87ac6 35
benkatz 22:60276ba87ac6 36 float v_offset = (fminf3(u, v, w) + fmaxf3(u, v, w))/2.0f;
benkatz 31:61eb6ae28215 37 *dtc_u = fminf(fmaxf(((u -v_offset)/v_bus + .5f), DTC_MIN), DTC_MAX);
benkatz 31:61eb6ae28215 38 *dtc_v = fminf(fmaxf(((v -v_offset)/v_bus + .5f), DTC_MIN), DTC_MAX);
benkatz 31:61eb6ae28215 39 *dtc_w = fminf(fmaxf(((w -v_offset)/v_bus + .5f), DTC_MIN), DTC_MAX);
benkatz 22:60276ba87ac6 40
benkatz 22:60276ba87ac6 41 }
benkatz 22:60276ba87ac6 42
benkatz 25:f5741040c4bb 43 void zero_current(int *offset_1, int *offset_2){ // Measure zero-offset of the current sensors
benkatz 22:60276ba87ac6 44 int adc1_offset = 0;
benkatz 22:60276ba87ac6 45 int adc2_offset = 0;
benkatz 22:60276ba87ac6 46 int n = 1024;
benkatz 25:f5741040c4bb 47 for (int i = 0; i<n; i++){ // Average n samples of the ADC
benkatz 27:501fee691e0e 48 TIM1->CCR3 = (PWM_ARR>>1)*(1.0f); // Write duty cycles
benkatz 27:501fee691e0e 49 TIM1->CCR2 = (PWM_ARR>>1)*(1.0f);
benkatz 27:501fee691e0e 50 TIM1->CCR1 = (PWM_ARR>>1)*(1.0f);
benkatz 26:2b865c00d7e9 51 ADC1->CR2 |= 0x40000000; // Begin sample and conversion
benkatz 22:60276ba87ac6 52 wait(.001);
benkatz 22:60276ba87ac6 53 adc2_offset += ADC2->DR;
benkatz 22:60276ba87ac6 54 adc1_offset += ADC1->DR;
benkatz 22:60276ba87ac6 55 }
benkatz 22:60276ba87ac6 56 *offset_1 = adc1_offset/n;
benkatz 22:60276ba87ac6 57 *offset_2 = adc2_offset/n;
benkatz 22:60276ba87ac6 58 }
benkatz 22:60276ba87ac6 59
benkatz 22:60276ba87ac6 60 void reset_foc(ControllerStruct *controller){
benkatz 28:8c7e29f719c5 61 TIM1->CCR3 = (PWM_ARR>>1)*(0.5f);
benkatz 28:8c7e29f719c5 62 TIM1->CCR1 = (PWM_ARR>>1)*(0.5f);
benkatz 28:8c7e29f719c5 63 TIM1->CCR2 = (PWM_ARR>>1)*(0.5f);
benkatz 28:8c7e29f719c5 64 controller->i_d_ref = 0;
benkatz 28:8c7e29f719c5 65 controller->i_q_ref = 0;
benkatz 28:8c7e29f719c5 66 controller->i_d = 0;
benkatz 28:8c7e29f719c5 67 controller->i_q = 0;
benkatz 22:60276ba87ac6 68 controller->q_int = 0;
benkatz 22:60276ba87ac6 69 controller->d_int = 0;
benkatz 28:8c7e29f719c5 70 controller->v_q = 0;
benkatz 28:8c7e29f719c5 71 controller->v_d = 0;
benkatz 22:60276ba87ac6 72 }
benkatz 22:60276ba87ac6 73
benkatz 22:60276ba87ac6 74
benkatz 22:60276ba87ac6 75 void commutate(ControllerStruct *controller, GPIOStruct *gpio, float theta){
benkatz 25:f5741040c4bb 76 /// Commutation Loop ///
benkatz 26:2b865c00d7e9 77
benkatz 25:f5741040c4bb 78 controller->loop_count ++;
benkatz 25:f5741040c4bb 79 if(PHASE_ORDER){ // Check current sensor ordering
benkatz 25:f5741040c4bb 80 controller->i_b = I_SCALE*(float)(controller->adc2_raw - controller->adc2_offset); // Calculate phase currents from ADC readings
benkatz 22:60276ba87ac6 81 controller->i_c = I_SCALE*(float)(controller->adc1_raw - controller->adc1_offset);
benkatz 22:60276ba87ac6 82 }
benkatz 22:60276ba87ac6 83 else{
benkatz 25:f5741040c4bb 84 controller->i_b = I_SCALE*(float)(controller->adc1_raw - controller->adc1_offset);
benkatz 22:60276ba87ac6 85 controller->i_c = I_SCALE*(float)(controller->adc2_raw - controller->adc2_offset);
benkatz 22:60276ba87ac6 86 }
benkatz 26:2b865c00d7e9 87 controller->i_a = -controller->i_b - controller->i_c;
benkatz 22:60276ba87ac6 88
benkatz 26:2b865c00d7e9 89 float s = FastSin(theta);
benkatz 26:2b865c00d7e9 90 float c = FastCos(theta);
benkatz 26:2b865c00d7e9 91 //dq0(controller->theta_elec, controller->i_a, controller->i_b, controller->i_c, &controller->i_d, &controller->i_q); //dq0 transform on currents
benkatz 27:501fee691e0e 92 controller->i_d = 0.6666667f*(c*controller->i_a + (0.86602540378f*s-.5f*c)*controller->i_b + (-0.86602540378f*s-.5f*c)*controller->i_c); ///Faster DQ0 Transform
benkatz 26:2b865c00d7e9 93 controller->i_q = 0.6666667f*(-s*controller->i_a - (-0.86602540378f*c-.5f*s)*controller->i_b - (0.86602540378f*c-.5f*s)*controller->i_c);
benkatz 28:8c7e29f719c5 94
benkatz 31:61eb6ae28215 95 //float cogging_current = 0.05f*s*controller->i_q_ref;
benkatz 25:f5741040c4bb 96
benkatz 25:f5741040c4bb 97 /// PI Controller ///
benkatz 22:60276ba87ac6 98 float i_d_error = controller->i_d_ref - controller->i_d;
benkatz 31:61eb6ae28215 99 float i_q_error = controller->i_q_ref - controller->i_q;// + cogging_current;
benkatz 22:60276ba87ac6 100 float v_d_ff = 2.0f*(2*controller->i_d_ref*R_PHASE); //feed-forward voltage
benkatz 28:8c7e29f719c5 101 float v_q_ff = controller->dtheta_elec*WB*1.73205081f;
benkatz 22:60276ba87ac6 102 controller->d_int += i_d_error;
benkatz 22:60276ba87ac6 103 controller->q_int += i_q_error;
benkatz 22:60276ba87ac6 104
benkatz 22:60276ba87ac6 105 //v_d_ff = 0;
benkatz 22:60276ba87ac6 106 //v_q_ff = 0;
benkatz 22:60276ba87ac6 107
benkatz 31:61eb6ae28215 108 limit_norm(&controller->d_int, &controller->q_int, V_BUS/(K_SCALE*I_BW*KI_Q)); // Limit integrators to prevent windup
benkatz 31:61eb6ae28215 109 controller->v_d = K_SCALE*I_BW*i_d_error + K_SCALE*I_BW*KI_D*controller->d_int;// + v_d_ff;
benkatz 31:61eb6ae28215 110 controller->v_q = K_SCALE*I_BW*i_q_error + K_SCALE*I_BW*KI_Q*controller->q_int;// + v_q_ff;
benkatz 22:60276ba87ac6 111
benkatz 28:8c7e29f719c5 112 //controller->v_q = 4.0f;;
benkatz 28:8c7e29f719c5 113 //controller->v_d = 0.0f;
benkatz 28:8c7e29f719c5 114
benkatz 22:60276ba87ac6 115 //controller->v_d = v_d_ff;
benkatz 22:60276ba87ac6 116 //controller->v_q = v_q_ff;
benkatz 22:60276ba87ac6 117
benkatz 29:0dbc822dd29a 118 limit_norm(&controller->v_d, &controller->v_q, 1.2f*controller->v_bus); // Normalize voltage vector to lie within curcle of radius v_bus
benkatz 26:2b865c00d7e9 119 //abc(controller->theta_elec, controller->v_d, controller->v_q, &controller->v_u, &controller->v_v, &controller->v_w); //inverse dq0 transform on voltages
benkatz 26:2b865c00d7e9 120
benkatz 27:501fee691e0e 121 controller->v_u = c*controller->v_d - s*controller->v_q; // Faster Inverse DQ0 transform
benkatz 26:2b865c00d7e9 122 controller->v_v = (0.86602540378f*s-.5f*c)*controller->v_d - (-0.86602540378f*c-.5f*s)*controller->v_q;
benkatz 26:2b865c00d7e9 123 controller->v_w = (-0.86602540378f*s-.5f*c)*controller->v_d - (0.86602540378f*c-.5f*s)*controller->v_q;
benkatz 22:60276ba87ac6 124 svm(controller->v_bus, controller->v_u, controller->v_v, controller->v_w, &controller->dtc_u, &controller->dtc_v, &controller->dtc_w); //space vector modulation
benkatz 22:60276ba87ac6 125
benkatz 22:60276ba87ac6 126
benkatz 25:f5741040c4bb 127 if(PHASE_ORDER){ // Check which phase order to use,
benkatz 31:61eb6ae28215 128 TIM1->CCR3 = (PWM_ARR)*(1.0f-controller->dtc_u); // Write duty cycles
benkatz 31:61eb6ae28215 129 TIM1->CCR2 = (PWM_ARR)*(1.0f-controller->dtc_v);
benkatz 31:61eb6ae28215 130 TIM1->CCR1 = (PWM_ARR)*(1.0f-controller->dtc_w);
benkatz 22:60276ba87ac6 131 }
benkatz 22:60276ba87ac6 132 else{
benkatz 27:501fee691e0e 133 TIM1->CCR3 = (PWM_ARR>>1)*(1.0f-controller->dtc_u);
benkatz 27:501fee691e0e 134 TIM1->CCR1 = (PWM_ARR>>1)*(1.0f-controller->dtc_v);
benkatz 31:61eb6ae28215 135 TIM1->CCR2 = (PWM_ARR>>1)*(1.0f-controller->dtc_w);
benkatz 22:60276ba87ac6 136 }
benkatz 25:f5741040c4bb 137
benkatz 25:f5741040c4bb 138 controller->theta_elec = theta; //For some reason putting this at the front breaks thins
benkatz 22:60276ba87ac6 139
benkatz 22:60276ba87ac6 140
benkatz 31:61eb6ae28215 141 if(controller->loop_count >400){
benkatz 22:60276ba87ac6 142 //controller->i_q_ref = -controller->i_q_ref;
benkatz 26:2b865c00d7e9 143 controller->loop_count = 0;
benkatz 22:60276ba87ac6 144
benkatz 28:8c7e29f719c5 145 //printf("%.2f %.2f %.2f\n\r", controller->i_a, controller->i_b, controller->i_c);
benkatz 31:61eb6ae28215 146 //printf("%f\n\r", controller->dtheta_mech*GR);
benkatz 22:60276ba87ac6 147 //pc.printf("%f %f %f\n\r", controller->i_a, controller->i_b, controller->i_c);
benkatz 22:60276ba87ac6 148 //pc.printf("%f %f\n\r", controller->i_d, controller->i_q);
benkatz 22:60276ba87ac6 149 //pc.printf("%d %d\n\r", controller->adc1_raw, controller->adc2_raw);
benkatz 26:2b865c00d7e9 150 }
benkatz 22:60276ba87ac6 151 }
benkatz 26:2b865c00d7e9 152
benkatz 26:2b865c00d7e9 153
benkatz 26:2b865c00d7e9 154 void torque_control(ControllerStruct *controller){
benkatz 28:8c7e29f719c5 155 float torque_ref = controller->kp*(controller->p_des - controller->theta_mech) + controller->t_ff + controller->kd*(controller->v_des - controller->dtheta_mech);
benkatz 26:2b865c00d7e9 156 //float torque_ref = -.1*(controller->p_des - controller->theta_mech);
benkatz 26:2b865c00d7e9 157 controller->i_q_ref = torque_ref/KT_OUT;
benkatz 26:2b865c00d7e9 158 controller->i_d_ref = 0;
benkatz 26:2b865c00d7e9 159 }
benkatz 26:2b865c00d7e9 160
benkatz 26:2b865c00d7e9 161
benkatz 22:60276ba87ac6 162 /*
benkatz 22:60276ba87ac6 163 void zero_encoder(ControllerStruct *controller, GPIOStruct *gpio, ){
benkatz 22:60276ba87ac6 164
benkatz 22:60276ba87ac6 165 }
benkatz 22:60276ba87ac6 166 */