David Lakata / Mbed 2 deprecated QuadTrio

ESE350 project, Spring 2016, University of Pennsylvania

Dependencies:   Adafruit9-DOf Receiver mbed-rtos mbed

quadcopter.cpp@31:d473eacfc271, 2016-04-21 (annotated)

Committer:
ivo_david_michelle
Date:
Thu Apr 21 20:57:19 2016 +0000
Revision:
31:d473eacfc271
Parent:
30:4820042e67b5
Child:
32:e12b01c94b4a
implemented integral control

Who changed what in which revision?

UserRevisionLine numberNew contents of line
ivo_david_michelle 6:6f3ffd97d808 1 #include "quadcopter.h"
ivo_david_michelle 9:f1bd96708a21 2 #include "sensor.h"
ivo_david_michelle 14:64b06476d943 3 #include "receiver.h"
ivo_david_michelle 14:64b06476d943 4 #include <string>
ivo_david_michelle 23:04338a5ef404 5
ivo_david_michelle 23:04338a5ef404 6 #ifndef M_PI
ivo_david_michelle 23:04338a5ef404 7 #define M_PI 3.14159265358979323846
ivo_david_michelle 23:04338a5ef404 8 #endif
ivo_david_michelle 9:f1bd96708a21 9
ivo_david_michelle 10:e7d1801e966a 10 // constructor
ivo_david_michelle 15:90e07946186f 11 Quadcopter::Quadcopter(Serial *pcPntr, MRF24J40 *mrfPntr)
ivo_david_michelle 24:e220fbb70ded 12 {
ivo_david_michelle 14:64b06476d943 13 pc_= pcPntr; // enable printing
ivo_david_michelle 23:04338a5ef404 14 g_= 9.81;
ivo_david_michelle 23:04338a5ef404 15 l_= 0.25;
ivo_david_michelle 23:04338a5ef404 16 gamma_= 1;
ivo_david_michelle 24:e220fbb70ded 17
ivo_david_michelle 31:d473eacfc271 18 zeroVelPwm = 0.11;
ivo_david_michelle 31:d473eacfc271 19 maxPwm = 0.15;
ivo_david_michelle 27:11116aa69f32 20
ivo_david_michelle 27:11116aa69f32 21 // control gains set s.t. 100% joystick results in 15% (actually: (maxPwm-zeroVelPwm+0.1)) duty cycle.
ivo_david_michelle 29:ae765492fa8b 22 kp_f_ = (maxPwm - zeroVelPwm) * 4 / 0.5;
ivo_david_michelle 30:4820042e67b5 23 kp_phi_ = 0.2 * (maxPwm - zeroVelPwm) * l_ / 0.5 * 4 / M_PI;
ivo_david_michelle 30:4820042e67b5 24 kp_theta_ = 0.2 * (maxPwm - zeroVelPwm) * l_ / 0.5 * 4 / M_PI;
ivo_david_michelle 29:ae765492fa8b 25 kp_psi_ = 0;
ivo_david_michelle 31:d473eacfc271 26 // kp_phi_ = 0;
ivo_david_michelle 31:d473eacfc271 27 // kp_theta_ = 0;
ivo_david_michelle 10:e7d1801e966a 28
ivo_david_michelle 10:e7d1801e966a 29 // derivative attitude control gains
ivo_david_michelle 30:4820042e67b5 30 kd_phi_ = 0.3 * (maxPwm - zeroVelPwm) * 2 / M_PI;
ivo_david_michelle 30:4820042e67b5 31 kd_theta_ = 0.3 * (maxPwm - zeroVelPwm) * 2 / M_PI;
ivo_david_michelle 29:ae765492fa8b 32 kd_psi_ = 0.1;
ivo_david_michelle 31:d473eacfc271 33 // kd_phi_ = 0;
ivo_david_michelle 31:d473eacfc271 34 //kd_theta_ = 0;
ivo_david_michelle 31:d473eacfc271 35
ivo_david_michelle 31:d473eacfc271 36 ki_phi_ = 0.5 * (maxPwm - zeroVelPwm)/(2*M_PI/4); // full control signal after 2s at pi/4 error
ivo_david_michelle 31:d473eacfc271 37 ki_theta_ = 0.5 * (maxPwm - zeroVelPwm)/(2*M_PI/4);
ivo_david_michelle 31:d473eacfc271 38
ivo_david_michelle 31:d473eacfc271 39 i_e_phi_ = 0;
ivo_david_michelle 31:d473eacfc271 40 i_e_theta_ = 0;
ivo_david_michelle 31:d473eacfc271 41 prev_time_ = 0;
ivo_david_michelle 31:d473eacfc271 42
ivo_david_michelle 31:d473eacfc271 43
ivo_david_michelle 31:d473eacfc271 44 max_integral_phi_ = 0.05/(ki_phi_ * (0.5/l_ + 0.25)); // influence of integral part smaller than 0.05
ivo_david_michelle 31:d473eacfc271 45 max_integral_theta_ = 0.05/(ki_theta_ * (0.5/l_ + 0.25));
ivo_david_michelle 31:d473eacfc271 46
ivo_david_michelle 10:e7d1801e966a 47
ivo_david_michelle 10:e7d1801e966a 48 // desired values (will come from joystick)
ivo_david_michelle 10:e7d1801e966a 49 F_des_ = 0; // desired thrust force (excluding weight compensation)
ivo_david_michelle 9:f1bd96708a21 50
ivo_david_michelle 9:f1bd96708a21 51 dof_ = Adafruit_9DOF();
ivo_david_michelle 9:f1bd96708a21 52 accel_ = Adafruit_LSM303_Accel_Unified(30301);
ivo_david_michelle 9:f1bd96708a21 53 mag_ = Adafruit_LSM303_Mag_Unified(30302);
ivo_david_michelle 9:f1bd96708a21 54 gyro_ = Adafruit_L3GD20_Unified(20);
ivo_david_michelle 24:e220fbb70ded 55
ivo_david_michelle 24:e220fbb70ded 56 // prepare for communication with remote control
ivo_david_michelle 16:2be2aab63198 57 rcTimer_.start();
ivo_david_michelle 15:90e07946186f 58 mrf_ = mrfPntr; // RF tranceiver to link with handheld.
ivo_david_michelle 15:90e07946186f 59 rcLength_ = 250;
ivo_david_michelle 16:2be2aab63198 60 mrf_->SetChannel(3); //Set the Channel. 0 is default, 15 is max
ivo_david_michelle 27:11116aa69f32 61
ivo_david_michelle 24:e220fbb70ded 62 initial_offsets_ = (offset*) malloc(sizeof(offset));
ivo_david_michelle 24:e220fbb70ded 63 initSensors(*this); // IMU
ivo_david_michelle 9:f1bd96708a21 64 }
ivo_david_michelle 9:f1bd96708a21 65
ivo_david_michelle 9:f1bd96708a21 66 void Quadcopter::readSensorValues()
ivo_david_michelle 9:f1bd96708a21 67 {
ivo_david_michelle 9:f1bd96708a21 68 accel_.getEvent(&accel_event_);
ivo_david_michelle 9:f1bd96708a21 69 if (dof_.accelGetOrientation(&accel_event_, &orientation_)) {
ivo_david_michelle 9:f1bd96708a21 70 }
ivo_david_michelle 9:f1bd96708a21 71 /* Calculate the heading using the magnetometer */
ivo_david_michelle 9:f1bd96708a21 72 mag_.getEvent(&mag_event_);
ivo_david_michelle 9:f1bd96708a21 73 if (dof_.magGetOrientation(SENSOR_AXIS_Z, &mag_event_, &orientation_)) {
ivo_david_michelle 9:f1bd96708a21 74 }
ivo_david_michelle 9:f1bd96708a21 75
ivo_david_michelle 13:291ba30c7806 76 gyro_.getEvent(&gyro_event_);
ivo_david_michelle 11:5c54826d23a7 77
ivo_david_michelle 24:e220fbb70ded 78 gyro_event_.gyro.x -= initial_offsets_->gyro_x;
ivo_david_michelle 24:e220fbb70ded 79 gyro_event_.gyro.y -= initial_offsets_->gyro_y;
ivo_david_michelle 24:e220fbb70ded 80 gyro_event_.gyro.z -= initial_offsets_->gyro_z;
ivo_david_michelle 24:e220fbb70ded 81 orientation_.roll -= initial_offsets_->roll;
ivo_david_michelle 24:e220fbb70ded 82 orientation_.pitch -= initial_offsets_->pitch;
ivo_david_michelle 24:e220fbb70ded 83 orientation_.heading -= initial_offsets_->heading;
ivo_david_michelle 13:291ba30c7806 84
ivo_david_michelle 10:e7d1801e966a 85 // angular velocities in body coordinate system
ivo_david_michelle 30:4820042e67b5 86 state_.p = gyro_event_.gyro.x * M_PI / 180;
ivo_david_michelle 30:4820042e67b5 87 state_.q = gyro_event_.gyro.y * M_PI / 180;
ivo_david_michelle 30:4820042e67b5 88 state_.r = gyro_event_.gyro.z * M_PI / 180;
ivo_david_michelle 24:e220fbb70ded 89
ivo_david_michelle 23:04338a5ef404 90 state_.phi = orientation_.roll * M_PI / 180;
ivo_david_michelle 28:61f7356325c3 91 state_.theta = -orientation_.pitch * M_PI / 180;
ivo_david_michelle 24:e220fbb70ded 92 state_.psi = orientation_.heading * M_PI / 180;
ivo_david_michelle 29:ae765492fa8b 93 //pc_->printf("Roll: %f\tPitch: %f\tYaw: %f\tVel x: %f\tVel y: %f\tVel z: %f\r\n", state_.phi, state_.theta, state_.psi, state_.p, state_.q, state_.r);
ivo_david_michelle 9:f1bd96708a21 94 }
ivo_david_michelle 9:f1bd96708a21 95
ivo_david_michelle 31:d473eacfc271 96 void Quadcopter::controller(float time)
ivo_david_michelle 10:e7d1801e966a 97 {
ivo_david_michelle 31:d473eacfc271 98
ivo_david_michelle 31:d473eacfc271 99 if (prev_time_ == 0) {
ivo_david_michelle 31:d473eacfc271 100 prev_time_ = time;
ivo_david_michelle 31:d473eacfc271 101 return;
ivo_david_michelle 31:d473eacfc271 102 }
ivo_david_michelle 31:d473eacfc271 103
ivo_david_michelle 31:d473eacfc271 104
ivo_david_michelle 10:e7d1801e966a 105 // PD controller
ivo_david_michelle 31:d473eacfc271 106 double e_phi = desiredState_.phi - state_.phi;
ivo_david_michelle 31:d473eacfc271 107 double e_theta = desiredState_.theta - state_.theta;
ivo_david_michelle 31:d473eacfc271 108
ivo_david_michelle 31:d473eacfc271 109 float dt = time - prev_time_;
ivo_david_michelle 31:d473eacfc271 110 i_e_phi_ = i_e_phi_ + e_phi * dt;
ivo_david_michelle 31:d473eacfc271 111 i_e_theta_ = i_e_theta_ + e_theta * dt;
ivo_david_michelle 31:d473eacfc271 112 i_e_phi_ = min(max_integral_phi_, i_e_phi_);
ivo_david_michelle 31:d473eacfc271 113 i_e_theta_ = min(max_integral_theta_, i_e_theta_);
ivo_david_michelle 31:d473eacfc271 114
ivo_david_michelle 29:ae765492fa8b 115 controlInput_.f = kp_f_ * F_des_;//m_*g_ + F_des_;
ivo_david_michelle 31:d473eacfc271 116 controlInput_.mx = kp_phi_ * e_phi + kd_phi_ * (desiredState_.p - state_.p) + ki_phi_ * i_e_phi_;
ivo_david_michelle 31:d473eacfc271 117 controlInput_.my = kp_theta_ * e_theta + kd_theta_ * (desiredState_.q - state_.q) + ki_theta_ * i_e_theta_;
ivo_david_michelle 29:ae765492fa8b 118 controlInput_.mz = kd_psi_ * desiredState_.r; // feedforward desired yaw rate. // kp_psi_*(desiredState_.psi-state_.psi)+kd_psi_*(desiredState_.r-state_.r);
ivo_david_michelle 24:e220fbb70ded 119
ivo_david_michelle 20:efa15ed008b4 120 // set pwm values
ivo_david_michelle 29:ae765492fa8b 121 double forcePerMotor = 0.25 * controlInput_.f;
ivo_david_michelle 29:ae765492fa8b 122 double yawMomentPerMotor = 0.25 / gamma_ * controlInput_.mz;
ivo_david_michelle 29:ae765492fa8b 123 double rollMomentPerMotor = 0.5 / l_ * controlInput_.mx;
ivo_david_michelle 29:ae765492fa8b 124 double pitchMomentPerMotor = 0.5 / l_ * controlInput_.my;
ivo_david_michelle 29:ae765492fa8b 125 motorPwm_.m1 = zeroVelPwm + forcePerMotor - pitchMomentPerMotor - yawMomentPerMotor;
ivo_david_michelle 29:ae765492fa8b 126 motorPwm_.m2 = zeroVelPwm + forcePerMotor + rollMomentPerMotor + yawMomentPerMotor;
ivo_david_michelle 29:ae765492fa8b 127 motorPwm_.m3 = zeroVelPwm + forcePerMotor + pitchMomentPerMotor - yawMomentPerMotor;
ivo_david_michelle 29:ae765492fa8b 128 motorPwm_.m4 = zeroVelPwm + forcePerMotor - rollMomentPerMotor + yawMomentPerMotor;
ivo_david_michelle 27:11116aa69f32 129
ivo_david_michelle 29:ae765492fa8b 130 // cut off at max PWM
ivo_david_michelle 30:4820042e67b5 131 //pc_->printf("m1: %f\tm2: %f\tm3: %f\tm4: %f\r\n", motorPwm_.m1, motorPwm_.m2, motorPwm_.m3, motorPwm_.m4);
ivo_david_michelle 31:d473eacfc271 132 motorPwm_.m1 = min(0.17, motorPwm_.m1);
ivo_david_michelle 27:11116aa69f32 133 motorPwm_.m2 = min(maxPwm, motorPwm_.m2);
ivo_david_michelle 27:11116aa69f32 134 motorPwm_.m3 = min(maxPwm, motorPwm_.m3);
ivo_david_michelle 27:11116aa69f32 135 motorPwm_.m4 = min(maxPwm, motorPwm_.m4);
ivo_david_michelle 31:d473eacfc271 136
ivo_david_michelle 31:d473eacfc271 137 prev_time_ = time;
ivo_david_michelle 13:291ba30c7806 138 }
ivo_david_michelle 10:e7d1801e966a 139
ivo_david_michelle 12:422963993df5 140 motors Quadcopter::getPwm()
ivo_david_michelle 11:5c54826d23a7 141 {
ivo_david_michelle 22:92401a4fec13 142 return motorPwm_;
ivo_david_michelle 22:92401a4fec13 143 }
ivo_david_michelle 20:efa15ed008b4 144
ivo_david_michelle 22:92401a4fec13 145 state Quadcopter::getState()
ivo_david_michelle 22:92401a4fec13 146 {
ivo_david_michelle 22:92401a4fec13 147 return state_;
ivo_david_michelle 11:5c54826d23a7 148 }
ivo_david_michelle 14:64b06476d943 149
ivo_david_michelle 24:e220fbb70ded 150 Adafruit_LSM303_Accel_Unified Quadcopter::getAccel()
ivo_david_michelle 24:e220fbb70ded 151 {
ivo_david_michelle 24:e220fbb70ded 152 return accel_;
ivo_david_michelle 24:e220fbb70ded 153 }
ivo_david_michelle 24:e220fbb70ded 154
ivo_david_michelle 24:e220fbb70ded 155 Adafruit_LSM303_Mag_Unified Quadcopter::getMag()
ivo_david_michelle 24:e220fbb70ded 156 {
ivo_david_michelle 24:e220fbb70ded 157 return mag_;
ivo_david_michelle 24:e220fbb70ded 158 }
ivo_david_michelle 24:e220fbb70ded 159
ivo_david_michelle 24:e220fbb70ded 160 Adafruit_L3GD20_Unified Quadcopter::getGyro()
ivo_david_michelle 24:e220fbb70ded 161 {
ivo_david_michelle 24:e220fbb70ded 162 return gyro_;
ivo_david_michelle 24:e220fbb70ded 163 }
ivo_david_michelle 24:e220fbb70ded 164
ivo_david_michelle 24:e220fbb70ded 165 offset* Quadcopter::getOffset()
ivo_david_michelle 24:e220fbb70ded 166 {
ivo_david_michelle 24:e220fbb70ded 167 return initial_offsets_;
ivo_david_michelle 24:e220fbb70ded 168 }
ivo_david_michelle 24:e220fbb70ded 169
ivo_david_michelle 24:e220fbb70ded 170 Adafruit_9DOF Quadcopter::getIMU()
ivo_david_michelle 24:e220fbb70ded 171 {
ivo_david_michelle 24:e220fbb70ded 172 return dof_;
ivo_david_michelle 24:e220fbb70ded 173 }
ivo_david_michelle 24:e220fbb70ded 174
ivo_david_michelle 27:11116aa69f32 175 double Quadcopter::getForce()
ivo_david_michelle 27:11116aa69f32 176 {
ivo_david_michelle 27:11116aa69f32 177 return F_des_;
ivo_david_michelle 27:11116aa69f32 178 }
ivo_david_michelle 27:11116aa69f32 179
ivo_david_michelle 24:e220fbb70ded 180 void Quadcopter::readRc()
ivo_david_michelle 24:e220fbb70ded 181 {
ivo_david_michelle 14:64b06476d943 182 uint8_t zero = 0;
ivo_david_michelle 14:64b06476d943 183 uint8_t *rssi = &zero;
ivo_david_michelle 14:64b06476d943 184
ivo_david_michelle 14:64b06476d943 185 uint8_t receive = 0;
ivo_david_michelle 14:64b06476d943 186
ivo_david_michelle 14:64b06476d943 187 char rxBuffer[rcLength_];
ivo_david_michelle 24:e220fbb70ded 188
ivo_david_michelle 27:11116aa69f32 189 float thrust;
ivo_david_michelle 27:11116aa69f32 190 float yaw;
ivo_david_michelle 27:11116aa69f32 191 float pitch;
ivo_david_michelle 27:11116aa69f32 192 float roll;
ivo_david_michelle 27:11116aa69f32 193 long long id;
ivo_david_michelle 24:e220fbb70ded 194
ivo_david_michelle 16:2be2aab63198 195 receive = rf_receive_rssi(*mrf_, rxBuffer, rssi, rcLength_ + 1);
ivo_david_michelle 16:2be2aab63198 196 if (receive > 0) {
ivo_david_michelle 17:96d0c72e413e 197 sscanf(rxBuffer, "%lld,%f,%f,%f,%f", &id, &thrust, &yaw, &pitch, &roll);
ivo_david_michelle 16:2be2aab63198 198 } else {
ivo_david_michelle 16:2be2aab63198 199 pc_->printf("Receive failure\r\n");
ivo_david_michelle 24:e220fbb70ded 200 }
ivo_david_michelle 24:e220fbb70ded 201
ivo_david_michelle 25:d44610851105 202 // convert to radians, range is = +-40° or +-0.698132 radians
ivo_david_michelle 28:61f7356325c3 203 desiredState_.phi = -((roll - 0.5) * 80) * M_PI / 180; // minus, because joystick to right should result in positive moment
ivo_david_michelle 25:d44610851105 204 desiredState_.theta = ((pitch - 0.5) * 80) * M_PI / 180;
ivo_david_michelle 27:11116aa69f32 205 desiredState_.r = yaw-0.5; // number between 0 and 1 //((yaw - 0.5) * 80) * M_PI / 180;
ivo_david_michelle 30:4820042e67b5 206 F_des_ = thrust-0.5; // number between 0 and 1 -> number between -0.5 and 0.5. //((thrust - 0.5) * 80) * M_PI / 180;
ivo_david_michelle 27:11116aa69f32 207
ivo_david_michelle 25:d44610851105 208 // print id with thrust, yaw, pitch, and roll
ivo_david_michelle 28:61f7356325c3 209 //pc_->printf("%lld: thrust: %f, yaw: %f, pitch: %f, roll: %f\r\n", id, F_des_, desiredState_.psi, desiredState_.theta, desiredState_.phi);
ivo_david_michelle 14:64b06476d943 210 }
ivo_david_michelle 14:64b06476d943 211