Sebastian Uribe / Mbed OS pan_flipping

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Dependencies:   MatrixMath Matrix ExperimentServer QEI_pmw MotorShield

main.cpp@32:c60a5d33cd79, 2020-11-02 (annotated)

Committer:
suribe
Date:
Mon Nov 02 21:26:44 2020 +0000
Revision:
32:c60a5d33cd79
Parent:
31:4424902a0fd0
Child:
34:9a24d0f718ac
k

Who changed what in which revision?

UserRevisionLine numberNew contents of line
pwensing 0:43448bf056e8 1 #include "mbed.h"
pwensing 0:43448bf056e8 2 #include "rtos.h"
pwensing 0:43448bf056e8 3 #include "EthernetInterface.h"
pwensing 0:43448bf056e8 4 #include "ExperimentServer.h"
pwensing 0:43448bf056e8 5 #include "QEI.h"
saloutos 16:f9ea2b2d410f 6 #include "BezierCurve.h"
elijahsj 6:1faceb53dabe 7 #include "MotorShield.h"
elijahsj 13:3a1f4e09789b 8 #include "HardwareSetup.h"
saloutos 26:5822d4d8dca7 9 #include "Matrix.h"
saloutos 26:5822d4d8dca7 10 #include "MatrixMath.h"
pwensing 0:43448bf056e8 11
saloutos 16:f9ea2b2d410f 12 #define BEZIER_ORDER_FOOT 7
saloutos 17:1bb5aa45826e 13 #define NUM_INPUTS (12 + 2*(BEZIER_ORDER_FOOT+1))
saloutos 16:f9ea2b2d410f 14 #define NUM_OUTPUTS 19
pwensing 0:43448bf056e8 15
saloutos 16:f9ea2b2d410f 16 #define PULSE_TO_RAD (2.0f*3.14159f / 1200.0f)
saloutos 16:f9ea2b2d410f 17
saloutos 16:f9ea2b2d410f 18 // Initializations
pwensing 0:43448bf056e8 19 Serial pc(USBTX, USBRX); // USB Serial Terminal
pwensing 0:43448bf056e8 20 ExperimentServer server; // Object that lets us communicate with MATLAB
elijahsj 5:1ab9b2527794 21 Timer t; // Timer to measure elapsed time of experiment
elijahsj 5:1ab9b2527794 22
elijahsj 5:1ab9b2527794 23 QEI encoderA(PE_9,PE_11, NC, 1200, QEI::X4_ENCODING); // MOTOR A ENCODER (no index, 1200 counts/rev, Quadrature encoding)
elijahsj 5:1ab9b2527794 24 QEI encoderB(PA_5, PB_3, NC, 1200, QEI::X4_ENCODING); // MOTOR B ENCODER (no index, 1200 counts/rev, Quadrature encoding)
elijahsj 5:1ab9b2527794 25 QEI encoderC(PC_6, PC_7, NC, 1200, QEI::X4_ENCODING); // MOTOR C ENCODER (no index, 1200 counts/rev, Quadrature encoding)
elijahsj 5:1ab9b2527794 26 QEI encoderD(PD_12, PD_13, NC, 1200, QEI::X4_ENCODING);// MOTOR D ENCODER (no index, 1200 counts/rev, Quadrature encoding)
elijahsj 5:1ab9b2527794 27
elijahsj 12:84a6dcb60422 28 MotorShield motorShield(12000); //initialize the motor shield with a period of 12000 ticks or ~20kHZ
saloutos 16:f9ea2b2d410f 29 Ticker currentLoop;
saloutos 16:f9ea2b2d410f 30
saloutos 26:5822d4d8dca7 31 Matrix MassMatrix(2,2);
saloutos 26:5822d4d8dca7 32 Matrix Jacobian(2,2);
saloutos 26:5822d4d8dca7 33 Matrix JacobianT(2,2);
saloutos 26:5822d4d8dca7 34 Matrix InverseMassMatrix(2,2);
saloutos 26:5822d4d8dca7 35 Matrix temp_product(2,2);
saloutos 26:5822d4d8dca7 36 Matrix Lambda(2,2);
saloutos 26:5822d4d8dca7 37
saloutos 16:f9ea2b2d410f 38 // Variables for q1
saloutos 16:f9ea2b2d410f 39 float current1;
saloutos 16:f9ea2b2d410f 40 float current_des1 = 0;
saloutos 16:f9ea2b2d410f 41 float prev_current_des1 = 0;
saloutos 16:f9ea2b2d410f 42 float current_int1 = 0;
saloutos 16:f9ea2b2d410f 43 float angle1;
saloutos 16:f9ea2b2d410f 44 float velocity1;
saloutos 16:f9ea2b2d410f 45 float duty_cycle1;
saloutos 16:f9ea2b2d410f 46 float angle1_init;
saloutos 16:f9ea2b2d410f 47
saloutos 16:f9ea2b2d410f 48 // Variables for q2
saloutos 16:f9ea2b2d410f 49 float current2;
saloutos 16:f9ea2b2d410f 50 float current_des2 = 0;
saloutos 16:f9ea2b2d410f 51 float prev_current_des2 = 0;
saloutos 16:f9ea2b2d410f 52 float current_int2 = 0;
saloutos 16:f9ea2b2d410f 53 float angle2;
saloutos 16:f9ea2b2d410f 54 float velocity2;
saloutos 16:f9ea2b2d410f 55 float duty_cycle2;
saloutos 16:f9ea2b2d410f 56 float angle2_init;
saloutos 16:f9ea2b2d410f 57
suribe 32:c60a5d33cd79 58
saloutos 16:f9ea2b2d410f 59
saloutos 16:f9ea2b2d410f 60 // Timing parameters
saloutos 16:f9ea2b2d410f 61 float current_control_period_us = 200.0f; // 5kHz current control loop
saloutos 16:f9ea2b2d410f 62 float impedance_control_period_us = 1000.0f; // 1kHz impedance control loop
saloutos 16:f9ea2b2d410f 63 float start_period, traj_period, end_period;
saloutos 16:f9ea2b2d410f 64
suribe 32:c60a5d33cd79 65 // Hardware kinematic parameters -- NEED PAN PARAMETERS
suribe 32:c60a5d33cd79 66 const float l_c1; //upper arm center of mass
suribe 32:c60a5d33cd79 67 const float l_B; //upper arm length
suribe 32:c60a5d33cd79 68 const float r_c2; //lower arm center of mass
suribe 32:c60a5d33cd79 69 const float l_C; //lower arm length
suribe 32:c60a5d33cd79 70
suribe 32:c60a5d33cd79 71 const float m1; //mass of upper arm
suribe 32:c60a5d33cd79 72 const float m2; //mass of lower arm
suribe 32:c60a5d33cd79 73
suribe 32:c60a5d33cd79 74 const float I1; //upper arm interia
suribe 32:c60a5d33cd79 75 const float I2; //lower arm inertia
suribe 32:c60a5d33cd79 76
suribe 32:c60a5d33cd79 77 const float N; //gear ratio
suribe 32:c60a5d33cd79 78 const float Ir; //motor inertia
suribe 32:c60a5d33cd79 79
saloutos 16:f9ea2b2d410f 80 // Control parameters
saloutos 19:562c08086d71 81 float current_Kp = 4.0f;
saloutos 19:562c08086d71 82 float current_Ki = 0.4f;
saloutos 19:562c08086d71 83 float current_int_max = 3.0f;
saloutos 16:f9ea2b2d410f 84 float duty_max;
saloutos 16:f9ea2b2d410f 85 float K_xx;
saloutos 16:f9ea2b2d410f 86 float K_yy;
saloutos 16:f9ea2b2d410f 87 float K_xy;
saloutos 16:f9ea2b2d410f 88 float D_xx;
saloutos 16:f9ea2b2d410f 89 float D_xy;
saloutos 16:f9ea2b2d410f 90 float D_yy;
saloutos 16:f9ea2b2d410f 91
saloutos 16:f9ea2b2d410f 92 // Model parameters
saloutos 17:1bb5aa45826e 93 float supply_voltage = 12; // motor supply voltage
saloutos 18:21c8d94eddee 94 float R = 2.0f; // motor resistance
saloutos 18:21c8d94eddee 95 float k_t = 0.18f; // motor torque constant
saloutos 17:1bb5aa45826e 96 float nu = 0.0005; // motor viscous friction
saloutos 16:f9ea2b2d410f 97
saloutos 16:f9ea2b2d410f 98 // Current control interrupt function
saloutos 16:f9ea2b2d410f 99 void CurrentLoop()
saloutos 16:f9ea2b2d410f 100 {
saloutos 19:562c08086d71 101 // This loop sets the motor voltage commands using PI current controllers with feedforward terms.
saloutos 16:f9ea2b2d410f 102
saloutos 16:f9ea2b2d410f 103 //use the motor shield as follows:
saloutos 16:f9ea2b2d410f 104 //motorShield.motorAWrite(DUTY CYCLE, DIRECTION), DIRECTION = 0 is forward, DIRECTION =1 is backwards.
saloutos 16:f9ea2b2d410f 105
saloutos 18:21c8d94eddee 106 current1 = -(((float(motorShield.readCurrentA())/65536.0f)*30.0f)-15.0f); // measure current
saloutos 18:21c8d94eddee 107 velocity1 = encoderA.getVelocity() * PULSE_TO_RAD; // measure velocity
saloutos 18:21c8d94eddee 108 float err_c1 = current_des1 - current1; // current errror
saloutos 18:21c8d94eddee 109 current_int1 += err_c1; // integrate error
saloutos 18:21c8d94eddee 110 current_int1 = fmaxf( fminf(current_int1, current_int_max), -current_int_max); // anti-windup
saloutos 18:21c8d94eddee 111 float ff1 = R*current_des1 + k_t*velocity1; // feedforward terms
saloutos 18:21c8d94eddee 112 duty_cycle1 = (ff1 + current_Kp*err_c1 + current_Ki*current_int1)/supply_voltage; // PI current controller
saloutos 16:f9ea2b2d410f 113
saloutos 16:f9ea2b2d410f 114 float absDuty1 = abs(duty_cycle1);
saloutos 16:f9ea2b2d410f 115 if (absDuty1 > duty_max) {
saloutos 16:f9ea2b2d410f 116 duty_cycle1 *= duty_max / absDuty1;
saloutos 16:f9ea2b2d410f 117 absDuty1 = duty_max;
saloutos 16:f9ea2b2d410f 118 }
saloutos 16:f9ea2b2d410f 119 if (duty_cycle1 < 0) { // backwards
saloutos 16:f9ea2b2d410f 120 motorShield.motorAWrite(absDuty1, 1);
saloutos 16:f9ea2b2d410f 121 } else { // forwards
saloutos 16:f9ea2b2d410f 122 motorShield.motorAWrite(absDuty1, 0);
saloutos 16:f9ea2b2d410f 123 }
saloutos 16:f9ea2b2d410f 124 prev_current_des1 = current_des1;
saloutos 16:f9ea2b2d410f 125
saloutos 18:21c8d94eddee 126 current2 = -(((float(motorShield.readCurrentB())/65536.0f)*30.0f)-15.0f); // measure current
saloutos 18:21c8d94eddee 127 velocity2 = encoderB.getVelocity() * PULSE_TO_RAD; // measure velocity
saloutos 18:21c8d94eddee 128 float err_c2 = current_des2 - current2; // current error
saloutos 18:21c8d94eddee 129 current_int2 += err_c2; // integrate error
saloutos 18:21c8d94eddee 130 current_int2 = fmaxf( fminf(current_int2, current_int_max), -current_int_max); // anti-windup
saloutos 18:21c8d94eddee 131 float ff2 = R*current_des2 + k_t*velocity2; // feedforward terms
saloutos 18:21c8d94eddee 132 duty_cycle2 = (ff2 + current_Kp*err_c2 + current_Ki*current_int2)/supply_voltage; // PI current controller
saloutos 16:f9ea2b2d410f 133
saloutos 16:f9ea2b2d410f 134 float absDuty2 = abs(duty_cycle2);
saloutos 16:f9ea2b2d410f 135 if (absDuty2 > duty_max) {
saloutos 16:f9ea2b2d410f 136 duty_cycle2 *= duty_max / absDuty2;
saloutos 16:f9ea2b2d410f 137 absDuty2 = duty_max;
saloutos 16:f9ea2b2d410f 138 }
saloutos 16:f9ea2b2d410f 139 if (duty_cycle2 < 0) { // backwards
saloutos 16:f9ea2b2d410f 140 motorShield.motorBWrite(absDuty2, 1);
saloutos 16:f9ea2b2d410f 141 } else { // forwards
saloutos 16:f9ea2b2d410f 142 motorShield.motorBWrite(absDuty2, 0);
saloutos 16:f9ea2b2d410f 143 }
saloutos 16:f9ea2b2d410f 144 prev_current_des2 = current_des2;
saloutos 16:f9ea2b2d410f 145 }
elijahsj 6:1faceb53dabe 146
elijahsj 4:7a1b35f081bb 147 int main (void)
elijahsj 4:7a1b35f081bb 148 {
saloutos 17:1bb5aa45826e 149 // Object for 7th order Cartesian foot trajectory
saloutos 17:1bb5aa45826e 150 BezierCurve rDesFoot_bez(2,BEZIER_ORDER_FOOT);
saloutos 17:1bb5aa45826e 151
pwensing 0:43448bf056e8 152 // Link the terminal with our server and start it up
pwensing 0:43448bf056e8 153 server.attachTerminal(pc);
pwensing 0:43448bf056e8 154 server.init();
elijahsj 13:3a1f4e09789b 155
pwensing 0:43448bf056e8 156 // Continually get input from MATLAB and run experiments
pwensing 0:43448bf056e8 157 float input_params[NUM_INPUTS];
elijahsj 5:1ab9b2527794 158 pc.printf("%f",input_params[0]);
elijahsj 5:1ab9b2527794 159
pwensing 0:43448bf056e8 160 while(1) {
saloutos 16:f9ea2b2d410f 161 // If there are new inputs, this code will run
pwensing 0:43448bf056e8 162 if (server.getParams(input_params,NUM_INPUTS)) {
suribe 32:c60a5d33cd79 163 // Get inputs from MATLAB
suribe 32:c60a5d33cd79 164 start_period = input_params[0]; // First buffer time, before trajectory
suribe 32:c60a5d33cd79 165 traj_period = input_params[1]; // Trajectory time/length
suribe 32:c60a5d33cd79 166 end_period = input_params[2]; // Second buffer time, after trajectory
saloutos 16:f9ea2b2d410f 167
suribe 32:c60a5d33cd79 168 l_c1 = input_params[3]; //upper arm center of mass
suribe 32:c60a5d33cd79 169 l_B = input_params[4]; //upper arm length
suribe 32:c60a5d33cd79 170 l_c2 = input_params[5]; //lower arm center of mass
suribe 32:c60a5d33cd79 171 l_C = input_params[6]; //lower arm length
suribe 32:c60a5d33cd79 172
suribe 32:c60a5d33cd79 173 m1 = input_params[7]; //mass of upper arm
suribe 32:c60a5d33cd79 174 m2 = input_params[8]; //mass of lower arm
suribe 32:c60a5d33cd79 175
suribe 32:c60a5d33cd79 176 I1 = input_params[9]; //upper arm interia
suribe 32:c60a5d33cd79 177 I2 = input_params[10]; //lower arm inertia
suribe 32:c60a5d33cd79 178
suribe 32:c60a5d33cd79 179 N = input_params[11]; //gear ratio
suribe 32:c60a5d33cd79 180 Ir = input_params[12]; //motor inertia
saloutos 16:f9ea2b2d410f 181
suribe 32:c60a5d33cd79 182 angle1_init = input_params[13]; // Initial angle for q1 (rad)
suribe 32:c60a5d33cd79 183 angle2_init = input_params[14]; // Initial angle for q2 (rad)
elijahsj 4:7a1b35f081bb 184
suribe 32:c60a5d33cd79 185 K_xx = input_params[15]; // Foot stiffness N/m
suribe 32:c60a5d33cd79 186 K_yy = input_params[16]; // Foot stiffness N/m
suribe 32:c60a5d33cd79 187 K_xy = input_params[17]; // Foot stiffness N/m
suribe 32:c60a5d33cd79 188 D_xx = input_params[18]; // Foot damping N/(m/s)
suribe 32:c60a5d33cd79 189 D_yy = input_params[19]; // Foot damping N/(m/s)
suribe 32:c60a5d33cd79 190 D_xy = input_params[20]; // Foot damping N/(m/s)
suribe 32:c60a5d33cd79 191 duty_max = input_params[21]; // Maximum duty factor
saloutos 16:f9ea2b2d410f 192
saloutos 19:562c08086d71 193 // Get foot trajectory points
saloutos 16:f9ea2b2d410f 194 float foot_pts[2*(BEZIER_ORDER_FOOT+1)];
saloutos 16:f9ea2b2d410f 195 for(int i = 0; i<2*(BEZIER_ORDER_FOOT+1);i++) {
saloutos 17:1bb5aa45826e 196 foot_pts[i] = input_params[12+i];
saloutos 16:f9ea2b2d410f 197 }
saloutos 16:f9ea2b2d410f 198 rDesFoot_bez.setPoints(foot_pts);
saloutos 16:f9ea2b2d410f 199
saloutos 16:f9ea2b2d410f 200 // Attach current loop interrupt
saloutos 16:f9ea2b2d410f 201 currentLoop.attach_us(CurrentLoop,current_control_period_us);
saloutos 16:f9ea2b2d410f 202
pwensing 0:43448bf056e8 203 // Setup experiment
pwensing 0:43448bf056e8 204 t.reset();
pwensing 0:43448bf056e8 205 t.start();
elijahsj 5:1ab9b2527794 206 encoderA.reset();
elijahsj 5:1ab9b2527794 207 encoderB.reset();
elijahsj 5:1ab9b2527794 208 encoderC.reset();
elijahsj 5:1ab9b2527794 209 encoderD.reset();
elijahsj 10:a40d180c305c 210
elijahsj 15:495333b2ccf1 211 motorShield.motorAWrite(0, 0); //turn motor A off
saloutos 16:f9ea2b2d410f 212 motorShield.motorBWrite(0, 0); //turn motor B off
saloutos 16:f9ea2b2d410f 213
pwensing 0:43448bf056e8 214 // Run experiment
saloutos 16:f9ea2b2d410f 215 while( t.read() < start_period + traj_period + end_period) {
saloutos 16:f9ea2b2d410f 216
saloutos 19:562c08086d71 217 // Read encoders to get motor states
saloutos 16:f9ea2b2d410f 218 angle1 = encoderA.getPulses() *PULSE_TO_RAD + angle1_init;
saloutos 16:f9ea2b2d410f 219 velocity1 = encoderA.getVelocity() * PULSE_TO_RAD;
saloutos 16:f9ea2b2d410f 220
saloutos 16:f9ea2b2d410f 221 angle2 = encoderB.getPulses() * PULSE_TO_RAD + angle2_init;
saloutos 16:f9ea2b2d410f 222 velocity2 = encoderB.getVelocity() * PULSE_TO_RAD;
saloutos 16:f9ea2b2d410f 223
saloutos 16:f9ea2b2d410f 224 const float th1 = angle1;
saloutos 16:f9ea2b2d410f 225 const float th2 = angle2;
saloutos 16:f9ea2b2d410f 226 const float dth1= velocity1;
saloutos 16:f9ea2b2d410f 227 const float dth2= velocity2;
saloutos 16:f9ea2b2d410f 228
saloutos 16:f9ea2b2d410f 229 // Calculate the Jacobian
suribe 29:a88dd750fdbd 230 float Jx_th1 = l_AC*cos(th1+th2)+l_DE*cos(th1)+l_OB*cos(th1);
suribe 29:a88dd750fdbd 231 float Jx_th2 = l_AC*cos(th1+th2);
suribe 29:a88dd750fdbd 232 float Jy_th1 = l_AC*sin(th1+th2)+l_DE*sin(th1)+l_OB*sin(th1);
suribe 29:a88dd750fdbd 233 float Jy_th2 = l_AC*sin(th1+th2);
saloutos 19:562c08086d71 234
saloutos 17:1bb5aa45826e 235 // Calculate the forward kinematics (position and velocity)
suribe 29:a88dd750fdbd 236 float xFoot = l_DE*sin(th1)+l_OB*sin(th1)+l_AC*sin(th1+th2);
suribe 29:a88dd750fdbd 237 float yFoot = -l_DE*cos(th1)-l_OB*cos(th1)-l_AC*cos(th1+th2);
suribe 29:a88dd750fdbd 238 float dxFoot = dth1*(l_AC*cos(th1+th2)+l_DE*cos(th1)+l_OB*cos(th1))+dth2*l_AC*cos(th1+th2);
suribe 29:a88dd750fdbd 239 float dyFoot = dth1*(l_AC*sin(th1+th2)+l_DE*sin(th1)+l_OB*sin(th1))+dth2*l_AC*sin(th1+th2);
suribe 29:a88dd750fdbd 240
saloutos 16:f9ea2b2d410f 241
saloutos 16:f9ea2b2d410f 242 // Set gains based on buffer and traj times, then calculate desired x,y from Bezier trajectory at current time if necessary
saloutos 16:f9ea2b2d410f 243 float teff = 0;
saloutos 16:f9ea2b2d410f 244 float vMult = 0;
saloutos 16:f9ea2b2d410f 245 if( t < start_period) {
saloutos 16:f9ea2b2d410f 246 if (K_xx > 0 || K_yy > 0) {
saloutos 28:22530fdc149b 247 K_xx = 100;
saloutos 28:22530fdc149b 248 K_yy = 100;
saloutos 28:22530fdc149b 249 D_xx = 5;
saloutos 28:22530fdc149b 250 D_yy = 5;
saloutos 16:f9ea2b2d410f 251 K_xy = 0;
saloutos 16:f9ea2b2d410f 252 D_xy = 0;
saloutos 16:f9ea2b2d410f 253 }
saloutos 16:f9ea2b2d410f 254 teff = 0;
saloutos 16:f9ea2b2d410f 255 }
saloutos 16:f9ea2b2d410f 256 else if (t < start_period + traj_period)
saloutos 16:f9ea2b2d410f 257 {
suribe 32:c60a5d33cd79 258 K_xx = input_params[15]; // Foot stiffness N/m
suribe 32:c60a5d33cd79 259 K_yy = input_params[16]; // Foot stiffness N/m
suribe 32:c60a5d33cd79 260 K_xy = input_params[17]; // Foot stiffness N/m
suribe 32:c60a5d33cd79 261 D_xx = input_params[18]; // Foot damping N/(m/s)
suribe 32:c60a5d33cd79 262 D_yy = input_params[19]; // Foot damping N/(m/s)
suribe 32:c60a5d33cd79 263 D_xy = input_params[20]; // Foot damping N/(m/s)
saloutos 16:f9ea2b2d410f 264 teff = (t-start_period);
saloutos 16:f9ea2b2d410f 265 vMult = 1;
saloutos 16:f9ea2b2d410f 266 }
elijahsj 4:7a1b35f081bb 267 else
saloutos 16:f9ea2b2d410f 268 {
saloutos 17:1bb5aa45826e 269 teff = traj_period;
saloutos 17:1bb5aa45826e 270 vMult = 0;
saloutos 16:f9ea2b2d410f 271 }
saloutos 16:f9ea2b2d410f 272
saloutos 24:26a515ebb7cf 273 // Get desired foot positions and velocities
saloutos 16:f9ea2b2d410f 274 float rDesFoot[2] , vDesFoot[2];
saloutos 16:f9ea2b2d410f 275 rDesFoot_bez.evaluate(teff/traj_period,rDesFoot);
saloutos 16:f9ea2b2d410f 276 rDesFoot_bez.evaluateDerivative(teff/traj_period,vDesFoot);
saloutos 16:f9ea2b2d410f 277 vDesFoot[0]/=traj_period;
saloutos 16:f9ea2b2d410f 278 vDesFoot[1]/=traj_period;
saloutos 16:f9ea2b2d410f 279 vDesFoot[0]*=vMult;
saloutos 16:f9ea2b2d410f 280 vDesFoot[1]*=vMult;
saloutos 17:1bb5aa45826e 281
saloutos 19:562c08086d71 282 // Calculate the inverse kinematics (joint positions and velocities) for desired joint angles
suribe 29:a88dd750fdbd 283 float xFootd = -rDesFoot[0];
suribe 29:a88dd750fdbd 284 float yFootd = rDesFoot[1];
suribe 29:a88dd750fdbd 285 float l_OE = sqrt( (pow(xFootd,2) + pow(yFootd,2)) );
saloutos 17:1bb5aa45826e 286 float alpha = abs(acos( (pow(l_OE,2) - pow(l_AC,2) - pow((l_OB+l_DE),2))/(-2.0f*l_AC*(l_OB+l_DE)) ));
saloutos 18:21c8d94eddee 287 float th2_des = -(3.14159f - alpha);
suribe 29:a88dd750fdbd 288 float th1_des = -((3.14159f/2.0f) + atan2(yFootd,xFootd) - abs(asin( (l_AC/l_OE)*sin(alpha) )));
saloutos 17:1bb5aa45826e 289
saloutos 17:1bb5aa45826e 290 float dd = (Jx_th1*Jy_th2 - Jx_th2*Jy_th1);
saloutos 17:1bb5aa45826e 291 float dth1_des = (1.0f/dd) * ( Jy_th2*vDesFoot[0] - Jx_th2*vDesFoot[1] );
saloutos 17:1bb5aa45826e 292 float dth2_des = (1.0f/dd) * ( -Jy_th1*vDesFoot[0] + Jx_th1*vDesFoot[1] );
saloutos 17:1bb5aa45826e 293
saloutos 16:f9ea2b2d410f 294 // Calculate error variables
saloutos 19:562c08086d71 295 float e_x = 0;
saloutos 19:562c08086d71 296 float e_y = 0;
saloutos 19:562c08086d71 297 float de_x = 0;
saloutos 19:562c08086d71 298 float de_y = 0;
saloutos 17:1bb5aa45826e 299
saloutos 16:f9ea2b2d410f 300 // Calculate virtual force on foot
suribe 29:a88dd750fdbd 301 float xdelta = -xFootd - xFoot;
suribe 29:a88dd750fdbd 302 float ydelta = yFootd - yFoot;
suribe 29:a88dd750fdbd 303 float dydelta = vDesFoot[1] - dyFoot;
suribe 29:a88dd750fdbd 304 float dxdelta = vDesFoot[0] - dxFoot;
suribe 29:a88dd750fdbd 305 float fx = K_xx*xdelta+K_xy*ydelta+D_xx*dxdelta+D_xy*dydelta;
suribe 29:a88dd750fdbd 306 float fy = K_yy*ydelta+K_xy*xdelta+D_yy*dydelta+D_xy*dxdelta;
suribe 29:a88dd750fdbd 307
suribe 29:a88dd750fdbd 308 float t1 = Jx_th1*fx + Jy_th1*fy;
suribe 29:a88dd750fdbd 309 float t2 = Jx_th2*fx + Jy_th2*fy;
saloutos 26:5822d4d8dca7 310
saloutos 26:5822d4d8dca7 311 // Calculate mass matrix elements
suribe 29:a88dd750fdbd 312 float M11 = I1 + I2 + I3 + I4 + Ir + Ir*N*N + l_AC*l_AC*m4 + l_A_m3*l_A_m3*m3 + l_B_m2*l_B_m2*m2 + l_C_m4*l_C_m4*m4 + l_OA*l_OA*m3 + l_OB*l_OB*m2 + l_OA*l_OA*m4 + l_O_m1*l_O_m1*m1 + 2*l_C_m4*l_OA*m4 + 2*l_AC*l_C_m4*m4*cos(th2) + 2*l_AC*l_OA*m4*cos(th2) + 2*l_A_m3*l_OA*m3*cos(th2) + 2*l_B_m2*l_OB*m2*cos(th2);
suribe 29:a88dd750fdbd 313 float M12 = I2 + I3 + l_AC*l_AC*m4 + l_A_m3*l_A_m3*m3 + l_B_m2*l_B_m2*m2 + Ir*N + l_AC*l_C_m4*m4*cos(th2) + l_AC*l_OA*m4*cos(th2) + l_A_m3*l_OA*m3*cos(th2) + l_B_m2*l_OB*m2*cos(th2);
suribe 29:a88dd750fdbd 314 float M22 = Ir*N*N + m4*l_AC*l_AC + m3*l_A_m3*l_A_m3 + m2*l_B_m2*l_B_m2 + I2 + I3;
suribe 29:a88dd750fdbd 315
saloutos 26:5822d4d8dca7 316 // Populate mass matrix
saloutos 26:5822d4d8dca7 317 MassMatrix.Clear();
saloutos 26:5822d4d8dca7 318 MassMatrix << M11 << M12
saloutos 26:5822d4d8dca7 319 << M12 << M22;
saloutos 26:5822d4d8dca7 320
saloutos 26:5822d4d8dca7 321 // Populate Jacobian matrix
saloutos 26:5822d4d8dca7 322 Jacobian.Clear();
saloutos 26:5822d4d8dca7 323 Jacobian << Jx_th1 << Jx_th2
saloutos 26:5822d4d8dca7 324 << Jy_th1 << Jy_th2;
saloutos 26:5822d4d8dca7 325
saloutos 26:5822d4d8dca7 326 // Calculate Lambda matrix
saloutos 26:5822d4d8dca7 327 JacobianT = MatrixMath::Transpose(Jacobian);
saloutos 26:5822d4d8dca7 328 InverseMassMatrix = MatrixMath::Inv(MassMatrix);
saloutos 26:5822d4d8dca7 329 temp_product = Jacobian*InverseMassMatrix*JacobianT;
saloutos 26:5822d4d8dca7 330 Lambda = MatrixMath::Inv(temp_product);
saloutos 26:5822d4d8dca7 331
saloutos 26:5822d4d8dca7 332 // Pull elements of Lambda matrix
saloutos 26:5822d4d8dca7 333 float L11 = Lambda.getNumber(1,1);
saloutos 26:5822d4d8dca7 334 float L12 = Lambda.getNumber(1,2);
saloutos 26:5822d4d8dca7 335 float L21 = Lambda.getNumber(2,1);
suribe 29:a88dd750fdbd 336 float L22 = Lambda.getNumber(2,2);
suribe 29:a88dd750fdbd 337
suribe 32:c60a5d33cd79 338 // Calculate desired motor torque
suribe 29:a88dd750fdbd 339 float t1_op = (Jx_th1*L11+Jy_th1*L21)*fx + (Jx_th1*L12+Jy_th1*L22)*fy;
suribe 29:a88dd750fdbd 340 float t2_op = (Jx_th2*L11+Jy_th2*L21)*fx + (Jx_th2*L12+Jy_th2*L22)*fy;
saloutos 18:21c8d94eddee 341
saloutos 19:562c08086d71 342 // Set desired currents
suribe 29:a88dd750fdbd 343 current_des1 = t1_op/k_t;
suribe 29:a88dd750fdbd 344 current_des2 = t2_op/k_t;
saloutos 26:5822d4d8dca7 345
saloutos 19:562c08086d71 346 // Form output to send to MATLAB
saloutos 16:f9ea2b2d410f 347 float output_data[NUM_OUTPUTS];
saloutos 16:f9ea2b2d410f 348 // current time
pwensing 0:43448bf056e8 349 output_data[0] = t.read();
saloutos 16:f9ea2b2d410f 350 // motor 1 state
saloutos 16:f9ea2b2d410f 351 output_data[1] = angle1;
saloutos 16:f9ea2b2d410f 352 output_data[2] = velocity1;
saloutos 16:f9ea2b2d410f 353 output_data[3] = current1;
saloutos 16:f9ea2b2d410f 354 output_data[4] = current_des1;
saloutos 16:f9ea2b2d410f 355 output_data[5] = duty_cycle1;
saloutos 16:f9ea2b2d410f 356 // motor 2 state
saloutos 16:f9ea2b2d410f 357 output_data[6] = angle2;
saloutos 16:f9ea2b2d410f 358 output_data[7] = velocity2;
saloutos 16:f9ea2b2d410f 359 output_data[8] = current2;
saloutos 16:f9ea2b2d410f 360 output_data[9] = current_des2;
saloutos 16:f9ea2b2d410f 361 output_data[10]= duty_cycle2;
saloutos 16:f9ea2b2d410f 362 // foot state
saloutos 16:f9ea2b2d410f 363 output_data[11] = xFoot;
saloutos 16:f9ea2b2d410f 364 output_data[12] = yFoot;
saloutos 17:1bb5aa45826e 365 output_data[13] = dxFoot;
saloutos 17:1bb5aa45826e 366 output_data[14] = dyFoot;
saloutos 17:1bb5aa45826e 367 output_data[15] = rDesFoot[0];
saloutos 17:1bb5aa45826e 368 output_data[16] = rDesFoot[1];
saloutos 17:1bb5aa45826e 369 output_data[17] = vDesFoot[0];
saloutos 17:1bb5aa45826e 370 output_data[18] = vDesFoot[1];
elijahsj 13:3a1f4e09789b 371
pwensing 0:43448bf056e8 372 // Send data to MATLAB
pwensing 0:43448bf056e8 373 server.sendData(output_data,NUM_OUTPUTS);
saloutos 16:f9ea2b2d410f 374
saloutos 16:f9ea2b2d410f 375 wait_us(impedance_control_period_us);
elijahsj 4:7a1b35f081bb 376 }
saloutos 16:f9ea2b2d410f 377
pwensing 0:43448bf056e8 378 // Cleanup after experiment
pwensing 0:43448bf056e8 379 server.setExperimentComplete();
saloutos 16:f9ea2b2d410f 380 currentLoop.detach();
elijahsj 12:84a6dcb60422 381 motorShield.motorAWrite(0, 0); //turn motor A off
saloutos 16:f9ea2b2d410f 382 motorShield.motorBWrite(0, 0); //turn motor B off
pwensing 0:43448bf056e8 383 } // end if
pwensing 0:43448bf056e8 384 } // end while
suribe 32:c60a5d33cd79 385 } // end main