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Dependencies: ExperimentServer MotorShield QEI_pmw
Diff: main.cpp
- Revision:
- 27:9f2dad72971f
- Parent:
- 26:0fc6264f5ef5
- Child:
- 28:925794e4178b
diff -r 0fc6264f5ef5 -r 9f2dad72971f main.cpp --- a/main.cpp Sun Oct 02 22:20:03 2022 +0000 +++ b/main.cpp Fri Nov 18 19:38:21 2022 +0000 @@ -6,18 +6,21 @@ #include "BezierCurve.h" #include "MotorShield.h" #include "HardwareSetup.h" - -#define BEZIER_ORDER_FOOT 7 -#define NUM_INPUTS (12 + 2*(BEZIER_ORDER_FOOT+1)) -#define NUM_OUTPUTS 19 - + +//#define BEZIER_ORDER_FOOT 7 +#define NUM_INPUTS 12 +#define NUM_OUTPUTS 6 + #define PULSE_TO_RAD (2.0f*3.14159f / 1200.0f) - + // Initializations Serial pc(USBTX, USBRX); // USB Serial Terminal ExperimentServer server; // Object that lets us communicate with MATLAB Timer t; // Timer to measure elapsed time of experiment +Timer hold; // Timer to measure how long to hold clicked position +DigitalIn clicker(PB_8); + QEI encoderA(PE_9,PE_11, NC, 1200, QEI::X4_ENCODING); // MOTOR A ENCODER (no index, 1200 counts/rev, Quadrature encoding) QEI encoderB(PA_5, PB_3, NC, 1200, QEI::X4_ENCODING); // MOTOR B ENCODER (no index, 1200 counts/rev, Quadrature encoding) QEI encoderC(PC_6, PC_7, NC, 1200, QEI::X4_ENCODING); // MOTOR C ENCODER (no index, 1200 counts/rev, Quadrature encoding) @@ -32,31 +35,20 @@ float prev_current_des1 = 0; float current_int1 = 0; float angle1; +float angle1_des; float velocity1; float duty_cycle1; float angle1_init; - -// Variables for q2 -float current2; -float current_des2 = 0; -float prev_current_des2 = 0; -float current_int2 = 0; -float angle2; -float velocity2; -float duty_cycle2; -float angle2_init; - + // Fixed kinematic parameters -const float l_OA=.011; -const float l_OB=.042; -const float l_AC=.096; -const float l_DE=.091; +const float l_1=.25; +const float l_OB=.5; // Timing parameters float current_control_period_us = 200.0f; // 5kHz current control loop float impedance_control_period_us = 1000.0f; // 1kHz impedance control loop float start_period, traj_period, end_period; - + // Control parameters float current_Kp = 4.0f; float current_Ki = 0.4f; @@ -68,17 +60,17 @@ float D_xx; float D_xy; float D_yy; - + // Model parameters float supply_voltage = 12; // motor supply voltage float R = 2.0f; // motor resistance float k_t = 0.18f; // motor torque constant float nu = 0.0005; // motor viscous friction - + // Current control interrupt function void CurrentLoop() { - // This loop sets the motor voltage commands using PI current controllers with feedforward terms. + // This loop sets the motor voltage commands using PI current controllers with feedforward terms. //use the motor shield as follows: //motorShield.motorAWrite(DUTY CYCLE, DIRECTION), DIRECTION = 0 is forward, DIRECTION =1 is backwards. @@ -103,33 +95,13 @@ } prev_current_des1 = current_des1; - current2 = -(((float(motorShield.readCurrentB())/65536.0f)*30.0f)-15.0f); // measure current - velocity2 = encoderB.getVelocity() * PULSE_TO_RAD; // measure velocity - float err_c2 = current_des2 - current2; // current error - current_int2 += err_c2; // integrate error - current_int2 = fmaxf( fminf(current_int2, current_int_max), -current_int_max); // anti-windup - float ff2 = R*current_des2 + k_t*velocity2; // feedforward terms - duty_cycle2 = (ff2 + current_Kp*err_c2 + current_Ki*current_int2)/supply_voltage; // PI current controller - - float absDuty2 = abs(duty_cycle2); - if (absDuty2 > duty_max) { - duty_cycle2 *= duty_max / absDuty2; - absDuty2 = duty_max; - } - if (duty_cycle2 < 0) { // backwards - motorShield.motorBWrite(absDuty2, 1); - } else { // forwards - motorShield.motorBWrite(absDuty2, 0); - } - prev_current_des2 = current_des2; - } - + int main (void) { - // Object for 7th order Cartesian foot trajectory - BezierCurve rDesFoot_bez(2,BEZIER_ORDER_FOOT); + // Object for 7th order Cartesian foo//t trajectory +// BezierCurve rDesFoot_bez(2,BEZIER_ORDER_FOOT); // Link the terminal with our server and start it up server.attachTerminal(pc); @@ -151,8 +123,8 @@ end_period = input_params[2]; // Second buffer time, after trajectory angle1_init = input_params[3]; // Initial angle for q1 (rad) - angle2_init = input_params[4]; // Initial angle for q2 (rad) - + angle1_des = input_params[4]; + K_xx = input_params[5]; // Foot stiffness N/m K_yy = input_params[6]; // Foot stiffness N/m K_xy = input_params[7]; // Foot stiffness N/m @@ -160,13 +132,15 @@ D_yy = input_params[9]; // Foot damping N/(m/s) D_xy = input_params[10]; // Foot damping N/(m/s) duty_max = input_params[11]; // Maximum duty factor + + float th1_des = angle1_init; // Get foot trajectory points - float foot_pts[2*(BEZIER_ORDER_FOOT+1)]; - for(int i = 0; i<2*(BEZIER_ORDER_FOOT+1);i++) { - foot_pts[i] = input_params[12+i]; - } - rDesFoot_bez.setPoints(foot_pts); +// float foot_pts[2*(BEZIER_ORDER_FOOT+1)]; +// for(int i = 0; i<2*(BEZIER_ORDER_FOOT+1);i++) { +// foot_pts[i] = input_params[12+i]; +// } +// rDesFoot_bez.setPoints(foot_pts); // Attach current loop interrupt currentLoop.attach_us(CurrentLoop,current_control_period_us); @@ -178,46 +152,40 @@ encoderB.reset(); encoderC.reset(); encoderD.reset(); - + motorShield.motorAWrite(0, 0); //turn motor A off - motorShield.motorBWrite(0, 0); //turn motor B off // Run experiment while( t.read() < start_period + traj_period + end_period) { // Read encoders to get motor states angle1 = encoderA.getPulses() *PULSE_TO_RAD + angle1_init; - velocity1 = encoderA.getVelocity() * PULSE_TO_RAD; - - angle2 = encoderB.getPulses() * PULSE_TO_RAD + angle2_init; - velocity2 = encoderB.getVelocity() * PULSE_TO_RAD; + velocity1 = encoderA.getVelocity() * PULSE_TO_RAD; const float th1 = angle1; - const float th2 = angle2; const float dth1= velocity1; - const float dth2= velocity2; - + // Calculate the Jacobian - float Jx_th1 = 0; - float Jx_th2 = 0; - float Jy_th1 = 0; - float Jy_th2 = 0; +// float Jx_th1 = l_AC*cos(th1+th2)+l_DE*cos(th1)+l_OB*cos(th1); +// float Jx_th2 = l_AC*cos(th1+th2); +// float Jy_th1 = l_AC*sin(th1+th2)+l_DE*sin(th1)+l_OB*sin(th1); +// float Jy_th2 = l_AC*sin(th1+th2); // Calculate the forward kinematics (position and velocity) - float xFoot = 0; - float yFoot = 0; - float dxFoot = 0; - float dyFoot = 0; + // float xFoot = l_AC*sin(th1+th2)+l_DE*sin(th1)+l_OB*sin(th1); +// float yFoot = -l_AC*cos(th1+th2)-l_DE*cos(th1)-l_OB*cos(th1); +// float dxFoot = velocity1*(l_AC*cos(th1+th2)+l_DE*cos(th1)+l_OB*cos(th1))+velocity2*l_AC*cos(th1+th2); +// float dyFoot = velocity1*(l_AC*sin(th1+th2)+l_DE*sin(th1)+l_OB*sin(th1))+velocity2*l_AC*sin(th1+th2); // Set gains based on buffer and traj times, then calculate desired x,y from Bezier trajectory at current time if necessary float teff = 0; float vMult = 0; if( t < start_period) { if (K_xx > 0 || K_yy > 0) { - K_xx = 1; // for joint space control, set this to 1; for Cartesian space control, set this to 50 - K_yy = 1; // for joint space control, set this to 1; for Cartesian space control, set this to 50 - D_xx = 0.1; // for joint space control, set this to 0.1; for Cartesian space control, set this to 2 - D_yy = 0.1; // for joint space control, set this to 0.1; for Cartesian space control, set this to 2 + K_xx = 50; // for joint space control, set this to 1; for Cartesian space control, set this to 50 + K_yy = 50; // for joint space control, set this to 1; for Cartesian space control, set this to 50 + D_xx = 2; // for joint space control, set this to 0.1; for Cartesian space control, set this to 2 + D_yy = 2; // for joint space control, set this to 0.1; for Cartesian space control, set this to 2 K_xy = 0; D_xy = 0; } @@ -241,51 +209,49 @@ } // Get desired foot positions and velocities - float rDesFoot[2] , vDesFoot[2]; - rDesFoot_bez.evaluate(teff/traj_period,rDesFoot); - rDesFoot_bez.evaluateDerivative(teff/traj_period,vDesFoot); - vDesFoot[0]/=traj_period; - vDesFoot[1]/=traj_period; - vDesFoot[0]*=vMult; - vDesFoot[1]*=vMult; - - // Calculate the inverse kinematics (joint positions and velocities) for desired joint angles - float xFoot_inv = -rDesFoot[0]; - float yFoot_inv = rDesFoot[1]; - float l_OE = sqrt( (pow(xFoot_inv,2) + pow(yFoot_inv,2)) ); - 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)) )); - float th2_des = -(3.14159f - alpha); - float th1_des = -((3.14159f/2.0f) + atan2(yFoot_inv,xFoot_inv) - abs(asin( (l_AC/l_OE)*sin(alpha) ))); +// float rDesFoot[2] , vDesFoot[2]; +// rDesFoot_bez.evaluate(teff/traj_period,rDesFoot); +// rDesFoot_bez.evaluateDerivative(teff/traj_period,vDesFoot); +// vDesFoot[0]/=traj_period; +// vDesFoot[1]/=traj_period; +// vDesFoot[0]*=vMult; +// vDesFoot[1]*=vMult; +// + // // Calculate the inverse kinematics (joint positions and velocities) for desired joint angles +// float xFoot_inv = -rDesFoot[0]; +// float yFoot_inv = rDesFoot[1]; +// float l_OE = sqrt( (pow(xFoot_inv,2) + pow(yFoot_inv,2)) ); +// 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)) )); +// float th2_des = -(3.14159f - alpha); +// float th1_des = -((3.14159f/2.0f) + atan2(yFoot_inv,xFoot_inv) - abs(asin( (l_AC/l_OE)*sin(alpha) ))); - float dd = (Jx_th1*Jy_th2 - Jx_th2*Jy_th1); - float dth1_des = (1.0f/dd) * ( Jy_th2*vDesFoot[0] - Jx_th2*vDesFoot[1] ); - float dth2_des = (1.0f/dd) * ( -Jy_th1*vDesFoot[0] + Jx_th1*vDesFoot[1] ); +// float dd = (Jx_th1*Jy_th2 - Jx_th2*Jy_th1); +// float dth1_des = (1.0f/dd) * ( Jy_th2*vDesFoot[0] - Jx_th2*vDesFoot[1] ); +// float dth2_des = (1.0f/dd) * ( -Jy_th1*vDesFoot[0] + Jx_th1*vDesFoot[1] ); - // Calculate error variables - float e_x = 0; - float e_y = 0; - float de_x = 0; - float de_y = 0; - - // Calculate virtual force on foot - float fx = 0; - float fy = 0; - - // Set desired currents - current_des1 = 0; - current_des2 = 0; - + +// Set desired currents +// current_des1 = (-K_xx*(angle1)-D_xx*(velocity1))/k_t; + while (hold.read() == 0 | hold.read() > 2){ + if(clicker.read() == 0) { + th1_des = angle1_init; + } + else { + th1_des = angle1_des; + hold.start(); + } + } + // Joint impedance // sub Kxx for K1, Dxx for D1, Kyy for K2, Dyy for D2 // Note: Be careful with signs now that you have non-zero desired angles! // Your equations should be of the form i_d = K1*(q1_d - q1) + D1*(dq1_d - dq1) -// current_des1 = 0; -// current_des2 = 0; + current_des1 = (K_xx*(th1_des-angle1))/k_t; +// current_des1 = (K_xx*(th1_des-angle1)+D_xx*(dth1_des-velocity1))/k_t; // Cartesian impedance - // Note: As with the joint space laws, be careful with signs! -// current_des1 = 0; -// current_des2 = 0; + // Note: As with the joint space laws, be careful with signs! +// current_des1 = t1/k_t; // Form output to send to MATLAB @@ -298,21 +264,16 @@ output_data[3] = current1; output_data[4] = current_des1; output_data[5] = duty_cycle1; - // motor 2 state - output_data[6] = angle2; - output_data[7] = velocity2; - output_data[8] = current2; - output_data[9] = current_des2; - output_data[10]= duty_cycle2; + // foot state - output_data[11] = xFoot; - output_data[12] = yFoot; - output_data[13] = dxFoot; - output_data[14] = dyFoot; - output_data[15] = rDesFoot[0]; - output_data[16] = rDesFoot[1]; - output_data[17] = vDesFoot[0]; - output_data[18] = vDesFoot[1]; +// output_data[11] = xFoot; +// output_data[12] = yFoot; +// output_data[13] = dxFoot; +// output_data[14] = dyFoot; +// output_data[15] = rDesFoot[0]; +// output_data[16] = rDesFoot[1]; +// output_data[17] = vDesFoot[0]; +// output_data[18] = vDesFoot[1]; // Send data to MATLAB server.sendData(output_data,NUM_OUTPUTS); @@ -324,7 +285,6 @@ server.setExperimentComplete(); currentLoop.detach(); motorShield.motorAWrite(0, 0); //turn motor A off - motorShield.motorBWrite(0, 0); //turn motor B off } // end if