Dammenisvoorcasuals / Mbed 2 deprecated chessRobot

control for robotic arm that can play chess using a granular gripper

Dependencies:   Encoder mbed HIDScope Servo MODSERIAL

Fork of chessRobot by a steenbeek

actuators.cpp@116:8b812e268b85, 2015-10-28 (annotated)

Committer:
annesteenbeek
Date:
Wed Oct 28 11:48:07 2015 +0100
Revision:
116:8b812e268b85
Parent:
115:d8d2968981f3
Child:
117:b1667291748d
calibration and kinematics

Who changed what in which revision?

UserRevisionLine numberNew contents of line
annesteenbeek 13:4837b36b9a68 1 #include "actuators.h"
annesteenbeek 13:4837b36b9a68 2 #include "PID.h"
annesteenbeek 13:4837b36b9a68 3 #include "mbed.h"
annesteenbeek 13:4837b36b9a68 4 #include "config.h"
annesteenbeek 13:4837b36b9a68 5 #include "encoder.h"
annesteenbeek 25:874675516927 6 #include "HIDScope.h"
annesteenbeek 107:de47331612d9 7 #include "buttons.h"
annesteenbeek 107:de47331612d9 8 #include "Servo.h"
annesteenbeek 98:25528494287d 9
annesteenbeek 109:026abd708dce 10 // Motor control constants
annesteenbeek 109:026abd708dce 11 #define pwm_frequency 50000 // still High, could be lowered
annesteenbeek 109:026abd708dce 12 #define PI 3.14159265
annesteenbeek 106:1773bf7b95c5 13
annesteenbeek 109:026abd708dce 14 // functions for controlling the motors
annesteenbeek 109:026abd708dce 15 bool motorsEnable = false;
annesteenbeek 109:026abd708dce 16 bool safetyOn = true;
annesteenbeek 76:0aa90e728e4a 17
annesteenbeek 6:b957d8809e7c 18
annesteenbeek 109:026abd708dce 19 double encoder1Counts = 0;
annesteenbeek 109:026abd708dce 20 double encoder2Counts = 0;
annesteenbeek 68:21cb054f1399 21
annesteenbeek 109:026abd708dce 22 bool direction1 = false; // CCW is false(positive rotation), CW is true (neg rotation)
annesteenbeek 109:026abd708dce 23 bool direction2 = false;
annesteenbeek 6:b957d8809e7c 24
annesteenbeek 109:026abd708dce 25 double motor1Pos = 0;
annesteenbeek 109:026abd708dce 26 double motor2Pos = 0;
annesteenbeek 6:b957d8809e7c 27
annesteenbeek 109:026abd708dce 28 double motor1Speed = 0;
annesteenbeek 109:026abd708dce 29 double motor2Speed = 0;
annesteenbeek 6:b957d8809e7c 30
annesteenbeek 109:026abd708dce 31 double motor1SetSpeed = 0;
annesteenbeek 109:026abd708dce 32 double motor2SetSpeed = 0;
annesteenbeek 6:b957d8809e7c 33
annesteenbeek 109:026abd708dce 34 double motor1PWM = 0;
annesteenbeek 109:026abd708dce 35 double motor2PWM = 0;
annesteenbeek 6:b957d8809e7c 36
annesteenbeek 109:026abd708dce 37 // Set PID values
annesteenbeek 109:026abd708dce 38 double Kp1 = 1;
annesteenbeek 109:026abd708dce 39 double Ki1 = 0;
annesteenbeek 109:026abd708dce 40 double Kd1 = 0;
annesteenbeek 0:525558a26464 41
annesteenbeek 109:026abd708dce 42 double Kp2 = 0.008;
annesteenbeek 109:026abd708dce 43 double Ki2 = 0.08;
annesteenbeek 109:026abd708dce 44 double Kd2 = 0;
annesteenbeek 20:3cba803cd771 45
annesteenbeek 109:026abd708dce 46 double motor1PrevCounts = 0;
annesteenbeek 109:026abd708dce 47 double motor2PrevCounts = 0;
annesteenbeek 109:026abd708dce 48 double prevTime = 0;
annesteenbeek 109:026abd708dce 49 double now = 0;
annesteenbeek 109:026abd708dce 50 double timechange;
annesteenbeek 109:026abd708dce 51
annesteenbeek 109:026abd708dce 52 // Set servo values
annesteenbeek 110:a6439e13be8b 53 double servoSpeed = 0;
annesteenbeek 109:026abd708dce 54 const int servoStartPos = 1300; // Servo ranges from 600ms(-90) to 2000ms(90), 1300 is 0 deg
annesteenbeek 26:0a9e4147a31a 55
annesteenbeek 109:026abd708dce 56 // Set calibration values
annesteenbeek 116:8b812e268b85 57 double motor1CalSpeed = -5; // deg/sec
annesteenbeek 116:8b812e268b85 58 double motor2CalSpeed = 5;
annesteenbeek 109:026abd708dce 59 bool springHit = false;
annesteenbeek 109:026abd708dce 60 float lastCall = 0;
annesteenbeek 109:026abd708dce 61 bool calibrating1 = true;
annesteenbeek 109:026abd708dce 62 bool calibrating2 = false;
annesteenbeek 116:8b812e268b85 63 double looseTime = 0;
annesteenbeek 98:25528494287d 64
annesteenbeek 109:026abd708dce 65 // Create object instances
annesteenbeek 109:026abd708dce 66 // Safety Pin
annesteenbeek 109:026abd708dce 67 DigitalIn safetyIn(safetyPin);
annesteenbeek 32:2006977785f5 68
annesteenbeek 109:026abd708dce 69 // Initialze motors
annesteenbeek 109:026abd708dce 70 PwmOut motor1(motor1PWMPin);
annesteenbeek 109:026abd708dce 71 PwmOut motor2(motor2PWMPin);
annesteenbeek 109:026abd708dce 72
annesteenbeek 109:026abd708dce 73 // initialize Servo
annesteenbeek 109:026abd708dce 74 Servo servo(servoPin);
annesteenbeek 98:25528494287d 75
annesteenbeek 98:25528494287d 76
annesteenbeek 109:026abd708dce 77 // Initialize encoders
annesteenbeek 109:026abd708dce 78 Encoder encoder1(enc1A, enc1B);
annesteenbeek 109:026abd708dce 79 Encoder encoder2(enc2A, enc2B);
annesteenbeek 25:874675516927 80
annesteenbeek 109:026abd708dce 81 // Set direction pins
annesteenbeek 109:026abd708dce 82 DigitalOut motor1Dir(motor1DirPin);
annesteenbeek 109:026abd708dce 83 DigitalOut motor2Dir(motor2DirPin);
annesteenbeek 26:0a9e4147a31a 84
annesteenbeek 109:026abd708dce 85 // create PID instances
annesteenbeek 109:026abd708dce 86 PID motor1PID(&motor1Speed, &motor1PWM, &motor1SetSpeed, Kp1, Ki1, Kd1);
annesteenbeek 109:026abd708dce 87 PID motor2PID(&motor2Speed, &motor2PWM, &motor2SetSpeed, Kp2, Ki2, Kd2);
annesteenbeek 31:8fbee6c92753 88
annesteenbeek 109:026abd708dce 89 Timer t;
annesteenbeek 25:874675516927 90
annesteenbeek 25:874675516927 91 void motorInit(){
annesteenbeek 25:874675516927 92
annesteenbeek 3:47c76be6d402 93 motor1Dir.write(direction1);
annesteenbeek 3:47c76be6d402 94 motor2Dir.write(direction2);
annesteenbeek 3:47c76be6d402 95
annesteenbeek 3:47c76be6d402 96 // Set motor PWM period
annesteenbeek 3:47c76be6d402 97 motor1.period(1/pwm_frequency);
annesteenbeek 3:47c76be6d402 98 motor2.period(1/pwm_frequency);
annesteenbeek 55:ee5257fb73df 99
annesteenbeek 55:ee5257fb73df 100 motor1PID.SetSampleTime(motorCall);
annesteenbeek 55:ee5257fb73df 101 motor2PID.SetSampleTime(motorCall);
annesteenbeek 55:ee5257fb73df 102
annesteenbeek 69:37f75a7d36d8 103 motor1PID.SetOutputLimits(0,1);
annesteenbeek 69:37f75a7d36d8 104 motor2PID.SetOutputLimits(0,1);
annesteenbeek 69:37f75a7d36d8 105
annesteenbeek 30:a20f16bf8dda 106 // Turn PID on
annesteenbeek 55:ee5257fb73df 107 motor1PID.SetMode(AUTOMATIC);
annesteenbeek 55:ee5257fb73df 108 motor2PID.SetMode(AUTOMATIC);
annesteenbeek 98:25528494287d 109
annesteenbeek 98:25528494287d 110 // set servo period
annesteenbeek 107:de47331612d9 111 servo.Enable(servoStartPos, 20000);
annesteenbeek 98:25528494287d 112
annesteenbeek 30:a20f16bf8dda 113 // start the timer
annesteenbeek 29:e4f3455aaa0b 114 t.start();
annesteenbeek 4:80e2280058ed 115 }
annesteenbeek 0:525558a26464 116
annesteenbeek 26:0a9e4147a31a 117
annesteenbeek 0:525558a26464 118 void motorControl(){
annesteenbeek 107:de47331612d9 119 // EMG signals to motor speeds
annesteenbeek 116:8b812e268b85 120 // const double scaleVel = 20;
annesteenbeek 116:8b812e268b85 121 // motor1SetSpeed = x_velocity*scaleVel;
annesteenbeek 116:8b812e268b85 122 // motor2SetSpeed = y_velocity*scaleVel;
annesteenbeek 116:8b812e268b85 123 // servoSpeed = z_velocity*scaleVel;
annesteenbeek 30:a20f16bf8dda 124 // get encoder positions in degrees
annesteenbeek 30:a20f16bf8dda 125 // 131.25:1 gear ratio
annesteenbeek 30:a20f16bf8dda 126 // getPosition uses X2 configuration, so 32 counts per revolution
annesteenbeek 30:a20f16bf8dda 127 // encoder reads CCW negative, and CW positive, so multiply by -1 to make CCW positive
annesteenbeek 68:21cb054f1399 128
annesteenbeek 68:21cb054f1399 129 encoder1Counts = encoder1.getPosition();
annesteenbeek 68:21cb054f1399 130 encoder2Counts = encoder2.getPosition();
annesteenbeek 68:21cb054f1399 131
annesteenbeek 68:21cb054f1399 132
annesteenbeek 116:8b812e268b85 133 motor1Pos = ((encoder1Counts/32)/131.25)*360;
annesteenbeek 116:8b812e268b85 134 motor2Pos = ((encoder2Counts/32)/131.25)*360;
annesteenbeek 3:47c76be6d402 135
annesteenbeek 0:525558a26464 136 // check if motor's are within rotational boundarys
annesteenbeek 30:a20f16bf8dda 137 // get encoder speeds in deg/sec
annesteenbeek 66:d1ab5904f8e5 138 now = t.read();
annesteenbeek 50:b0cf07ca53cf 139 timechange = (now - prevTime);
annesteenbeek 116:8b812e268b85 140 motor1Speed = ((((encoder1Counts - motor1PrevCounts)/32)/131.25)*360)/timechange;
annesteenbeek 116:8b812e268b85 141 motor2Speed = ((((encoder2Counts - motor2PrevCounts)/32)/131.25)*360)/timechange;
annesteenbeek 50:b0cf07ca53cf 142 prevTime = now;
annesteenbeek 68:21cb054f1399 143 motor1PrevCounts = encoder1Counts;
annesteenbeek 68:21cb054f1399 144 motor2PrevCounts = encoder2Counts;
annesteenbeek 29:e4f3455aaa0b 145
annesteenbeek 31:8fbee6c92753 146 // calculate motor setpoint speed in deg/sec from setpoint x/y speed
annesteenbeek 30:a20f16bf8dda 147
annesteenbeek 116:8b812e268b85 148 // exclude kinematics when still calibrating
annesteenbeek 116:8b812e268b85 149 if (calReady){
annesteenbeek 116:8b812e268b85 150 kinematics();
annesteenbeek 116:8b812e268b85 151 }
annesteenbeek 116:8b812e268b85 152
annesteenbeek 48:3cf1eaf34926 153 if(motorsEnable){ // only run motors if switch is enabled
annesteenbeek 32:2006977785f5 154 // compute new PID parameters using setpoint angle speeds and encoder speed
annesteenbeek 31:8fbee6c92753 155 writeMotors();
annesteenbeek 98:25528494287d 156 servoControl();
annesteenbeek 0:525558a26464 157 }else{
annesteenbeek 0:525558a26464 158 // write 0 to motors
annesteenbeek 2:95ba9f6f0128 159 motor1.write(0);
annesteenbeek 2:95ba9f6f0128 160 motor2.write(0);
annesteenbeek 0:525558a26464 161 }
annesteenbeek 0:525558a26464 162 }
annesteenbeek 0:525558a26464 163
annesteenbeek 31:8fbee6c92753 164 void writeMotors(){
annesteenbeek 54:c14c3bc48b8a 165 motor1PID.Compute(); // calculate PID outputs, output changes automatically
annesteenbeek 76:0aa90e728e4a 166 motor2PID.Compute();
annesteenbeek 31:8fbee6c92753 167 // write new values to motor's
annesteenbeek 82:4cc8f9ad3fec 168 if (motor1SetSpeed > 0 ){ // CCW rotation
annesteenbeek 116:8b812e268b85 169 direction1 = true;
annesteenbeek 84:df770ec4df61 170 motor1PID.SetOutputLimits(0,1); // change pid output direction
annesteenbeek 31:8fbee6c92753 171 }else{
annesteenbeek 116:8b812e268b85 172 direction1 = false; // CW rotation
annesteenbeek 83:8fa05f53fc73 173 motor1PID.SetOutputLimits(-1,0);
annesteenbeek 31:8fbee6c92753 174 }
annesteenbeek 82:4cc8f9ad3fec 175 if (motor2SetSpeed > 0 ){ // CCW rotation
annesteenbeek 116:8b812e268b85 176 direction2 = true;
annesteenbeek 83:8fa05f53fc73 177 motor2PID.SetOutputLimits(0,1);
annesteenbeek 68:21cb054f1399 178 }else{
annesteenbeek 116:8b812e268b85 179 direction2 = false; // CW rotation
annesteenbeek 83:8fa05f53fc73 180 motor2PID.SetOutputLimits(-1,0);
annesteenbeek 68:21cb054f1399 181 }
annesteenbeek 31:8fbee6c92753 182 motor1Dir.write(direction1);
annesteenbeek 31:8fbee6c92753 183 motor2Dir.write(direction2);
annesteenbeek 69:37f75a7d36d8 184
annesteenbeek 52:2ac9dee099ce 185 motor1.write(abs(motor1PWM));
annesteenbeek 76:0aa90e728e4a 186 motor2.write(abs(motor2PWM));
annesteenbeek 31:8fbee6c92753 187 }
annesteenbeek 31:8fbee6c92753 188
annesteenbeek 0:525558a26464 189 void servoControl(){
annesteenbeek 107:de47331612d9 190 servo.SetPosition(1300 + 700*servoSpeed);
annesteenbeek 25:874675516927 191 }
annesteenbeek 25:874675516927 192
annesteenbeek 116:8b812e268b85 193 const double motor1StartPos = (-10*32*131.25)/360; // angle to encoder counts
annesteenbeek 116:8b812e268b85 194 const double motor2StartPos = (114*32*131.25)/360;
annesteenbeek 116:8b812e268b85 195
annesteenbeek 106:1773bf7b95c5 196 bool calibrateMotors(){
annesteenbeek 98:25528494287d 197 safetyOn = false; // safety springs off
annesteenbeek 98:25528494287d 198 motorsEnable = true; // motors on
annesteenbeek 116:8b812e268b85 199 while (calibrating1 || calibrating2){
annesteenbeek 98:25528494287d 200 if (calibrating1){
annesteenbeek 116:8b812e268b85 201 motor1SetSpeed = motor1CalSpeed;
annesteenbeek 98:25528494287d 202 redLed.write(1); greenLed.write(0); blueLed.write(1);
annesteenbeek 116:8b812e268b85 203 if(safetyIn.read() !=1 && !springHit){ // check if arm reached safety position
annesteenbeek 116:8b812e268b85 204 encoder1.setPosition(motor1StartPos); // set motor 1 cal angle
annesteenbeek 116:8b812e268b85 205 motor1PrevCounts = motor1StartPos; // set previous count to prevent speed spike
annesteenbeek 116:8b812e268b85 206 motor1CalSpeed = -motor1CalSpeed; // move away
annesteenbeek 98:25528494287d 207 springHit = true;
annesteenbeek 116:8b812e268b85 208 looseTime = t.read(); // timer to compensate spring movement
annesteenbeek 98:25528494287d 209 }else{
annesteenbeek 116:8b812e268b85 210 // if hit and after is no longer touching spring and 0.5seconds passed
annesteenbeek 116:8b812e268b85 211 if(springHit && ((t.read() - looseTime) > 2)){
annesteenbeek 98:25528494287d 212 motor1SetSpeed = 0;
annesteenbeek 98:25528494287d 213 springHit = false;
annesteenbeek 115:d8d2968981f3 214 calibrating2 = true; // start calibrating 2
annesteenbeek 98:25528494287d 215 calibrating1 = false;
annesteenbeek 98:25528494287d 216 }
annesteenbeek 98:25528494287d 217 }
annesteenbeek 98:25528494287d 218 }
annesteenbeek 98:25528494287d 219 if (calibrating2){
annesteenbeek 116:8b812e268b85 220 motor2SetSpeed = motor2CalSpeed;
annesteenbeek 98:25528494287d 221 redLed.write(1); greenLed.write(1); blueLed.write(0);
annesteenbeek 116:8b812e268b85 222 if(safetyIn.read() !=1 && !springHit){ // check if arm reached safety position
annesteenbeek 116:8b812e268b85 223 encoder2.setPosition(motor2StartPos); // set motor 2 cal angle
annesteenbeek 116:8b812e268b85 224 motor2PrevCounts = motor2StartPos; // set previous cunt to prevent speed spike
annesteenbeek 116:8b812e268b85 225 motor2CalSpeed = -motor2CalSpeed; // move away
annesteenbeek 98:25528494287d 226 springHit = true;
annesteenbeek 116:8b812e268b85 227 looseTime = t.read();
annesteenbeek 98:25528494287d 228 }else{
annesteenbeek 116:8b812e268b85 229 if(springHit && ((t.read() - looseTime) > 2)){
annesteenbeek 98:25528494287d 230 motor2SetSpeed = 0;
annesteenbeek 98:25528494287d 231 springHit = false;
annesteenbeek 98:25528494287d 232 calibrating2 = false; // stop calibrating 2
annesteenbeek 98:25528494287d 233 }
annesteenbeek 98:25528494287d 234 }
annesteenbeek 98:25528494287d 235 }
annesteenbeek 116:8b812e268b85 236 // now = t.read(); // call motor using timer instead of wait
annesteenbeek 115:d8d2968981f3 237 // if(now - lastCall > motorCall){
annesteenbeek 98:25528494287d 238 motorControl();
annesteenbeek 116:8b812e268b85 239 wait(motorCall); // keep calling PID's with motorCall frequency
annesteenbeek 115:d8d2968981f3 240 // lastCall = now;
annesteenbeek 115:d8d2968981f3 241 // }
annesteenbeek 98:25528494287d 242
annesteenbeek 98:25528494287d 243 }
annesteenbeek 116:8b812e268b85 244 redLed.write(0); greenLed.write(1); blueLed.write(1);
annesteenbeek 99:7030e9790b1d 245 motorsEnable = false; // turn motor's off again
annesteenbeek 76:0aa90e728e4a 246 safetyOn = true; // turn safety on after callibration
annesteenbeek 110:a6439e13be8b 247 return true; // return true when finished
annesteenbeek 74:75be98779124 248 }
annesteenbeek 74:75be98779124 249
annesteenbeek 74:75be98779124 250
annesteenbeek 74:75be98779124 251 void safety(){
annesteenbeek 74:75be98779124 252 if (safetyOn){
annesteenbeek 81:71e7e98deb2c 253 if (safetyIn.read() != 1){
annesteenbeek 79:cf500b63f349 254 motorsEnable = false;
annesteenbeek 79:cf500b63f349 255 }
annesteenbeek 74:75be98779124 256 }
annesteenbeek 79:cf500b63f349 257 }
annesteenbeek 106:1773bf7b95c5 258
annesteenbeek 116:8b812e268b85 259 const double L1 = 0.436; // first arm in m
annesteenbeek 116:8b812e268b85 260 const double L2 = 0.120; // first arm in m
annesteenbeek 116:8b812e268b85 261 const double L3 = 0.255; // servo arm in m
annesteenbeek 116:8b812e268b85 262 const double Xmax = 0.3;
annesteenbeek 116:8b812e268b85 263 const double Xmin; = -0.3;
annesteenbeek 116:8b812e268b85 264 const double Ymax = 0.645;
annesteenbeek 116:8b812e268b85 265 const double Ymin = 0.33;
annesteenbeek 106:1773bf7b95c5 266
annesteenbeek 116:8b812e268b85 267
annesteenbeek 106:1773bf7b95c5 268
annesteenbeek 116:8b812e268b85 269 bool kinematics(){
annesteenbeek 116:8b812e268b85 270 // calculate current x and Y
annesteenbeek 116:8b812e268b85 271 double X = (L2+L3)*cos((motor1Pos + motor2Pos)*PI/180) + L1*cos(motor1Pos*PI/180);
annesteenbeek 116:8b812e268b85 272 double Y = (L2+L3)*sin((motor1Pos + motor2Pos)*PI/180) + L1*sin(motor1Pos*PI/180);
annesteenbeek 116:8b812e268b85 273 // check if x and y are within limits
annesteenbeek 116:8b812e268b85 274 // else Store the constraint line
annesteenbeek 116:8b812e268b85 275 // check if movement is in direction of constraint
annesteenbeek 116:8b812e268b85 276 // else return false no movement (anglespeed = 0)
annesteenbeek 116:8b812e268b85 277 // calculate required angle speeds
annesteenbeek 116:8b812e268b85 278 if( (X>Xmax && setXSpeed > 0 )|| \
annesteenbeek 116:8b812e268b85 279 (X<Xmin && setXSpeed < 0 )|| \
annesteenbeek 116:8b812e268b85 280 (Y>Ymax && setYSpeed > 0 )|| \
annesteenbeek 116:8b812e268b85 281 (Y<Ymin && setYSpeed < 0 ) \
annesteenbeek 116:8b812e268b85 282 ){
annesteenbeek 116:8b812e268b85 283 motor1SetSpeed = 0;
annesteenbeek 116:8b812e268b85 284 motor2SetSpeed = 0;
annesteenbeek 116:8b812e268b85 285 return false;
annesteenbeek 116:8b812e268b85 286 break;
annesteenbeek 116:8b812e268b85 287 }
annesteenbeek 116:8b812e268b85 288 motor1SetSpeed = (setXSpeed*cos((motor1Pos + motor2Pos)*PI/180) + \
annesteenbeek 116:8b812e268b85 289 setYSpeed*sin((motor1Pos + motor2Pos)*PI/180))/(L1*sin(motor2Pos*PI/180));
annesteenbeek 116:8b812e268b85 290 motor2SetSpeed = -(setXSpeed*(L2+L3)*cos((motor1Pos + motor2Pos)*PI/180) + \
annesteenbeek 116:8b812e268b85 291 setYSpeed*(L2+L3)*sin((motor1Pos + motor2Pos)*PI/180) + \
annesteenbeek 116:8b812e268b85 292 setXSpeed*L1*cos(motor1Pos*PI/180) + \
annesteenbeek 116:8b812e268b85 293 setYSpeed*L1*sin(motor1Pos*PI/180))/(L1*(L2+L3)*sin(motor2Pos*PI/180));
annesteenbeek 116:8b812e268b85 294
annesteenbeek 116:8b812e268b85 295 }