Michael Ernst Peter / Mbed OS PM2_Example_Line_Follower

Example project for the Line Follower robot.

Dependencies:   PM2_Libary Eigen

main.cpp@46:fd580fa68618, 2022-05-13 (annotated)

Committer:
pmic
Date:
Fri May 13 20:53:37 2022 +0000
Revision:
46:fd580fa68618
Parent:
45:5e1dd4117ed2
Child:
47:5ce234723e3a
Motion integrated into SpeedController and PositionController class

Who changed what in which revision?

UserRevisionLine numberNew contents of line
pmic 33:cff70742569d 1 #include <mbed.h>
pmic 33:cff70742569d 2 #include <math.h>
pmic 46:fd580fa68618 3 //#include <vector>
pmic 33:cff70742569d 4
pmic 17:c19b471f05cb 5 #include "PM2_Libary.h"
pmic 40:eb7f8dce5787 6 #include "Eigen/Dense.h"
pmic 6:e1fa1a2d7483 7
pmic 46:fd580fa68618 8 #include "Motion.h"
pmic 46:fd580fa68618 9
pmic 34:702246639f02 10 # define M_PI 3.14159265358979323846 // number pi
pmic 33:cff70742569d 11
pmic 24:86f1a63e35a0 12 // logical variable main task
pmic 24:86f1a63e35a0 13 bool do_execute_main_task = false; // this variable will be toggled via the user button (blue button) to or not to execute the main task
pmic 17:c19b471f05cb 14
pmic 24:86f1a63e35a0 15 // user button on nucleo board
pmic 24:86f1a63e35a0 16 Timer user_button_timer; // create Timer object which we use to check if user button was pressed for a certain time (robust against signal bouncing)
pmic 24:86f1a63e35a0 17 InterruptIn user_button(PC_13); // create InterruptIn interface object to evaluate user button falling and rising edge (no blocking code in ISR)
pmic 24:86f1a63e35a0 18 void user_button_pressed_fcn(); // custom functions which gets executed when user button gets pressed and released, definition below
pmic 24:86f1a63e35a0 19 void user_button_released_fcn();
pmic 6:e1fa1a2d7483 20
pmic 45:5e1dd4117ed2 21 // controller functions
pmic 45:5e1dd4117ed2 22 float ang_cntrl_fcn(const float& Kp, const float& Kp_nl, const float& angle);
pmic 45:5e1dd4117ed2 23 float vel_cntrl_v1_fcn(const float& vel_max, const float& vel_min, const float& ang_max, const float& angle);
pmic 45:5e1dd4117ed2 24 float vel_cntrl_v2_fcn(const float& wheel_speed_max, const float& b, const float& robot_omega, const Eigen::Matrix2f& Cwheel2robot);
pmic 38:6d11788e14c0 25
pmic 46:fd580fa68618 26 float speed = 0.0f;
pmic 46:fd580fa68618 27 float motionspeed = 0.0f;
pmic 46:fd580fa68618 28
pmic 1:93d997d6b232 29 int main()
pmic 46:fd580fa68618 30 {
pmic 45:5e1dd4117ed2 31 // while loop gets executed every main_task_period_ms milliseconds
pmic 45:5e1dd4117ed2 32 const int main_task_period_ms = 10; // define main task period time in ms e.g. 50 ms -> main task runns 20 times per second
pmic 45:5e1dd4117ed2 33 Timer main_task_timer; // create Timer object which we use to run the main task every main task period time in ms
pmic 45:5e1dd4117ed2 34
pmic 45:5e1dd4117ed2 35 // led on nucleo board
pmic 45:5e1dd4117ed2 36 DigitalOut user_led(LED1); // create DigitalOut object to command user led
pmic 45:5e1dd4117ed2 37
pmic 45:5e1dd4117ed2 38 // Sharp GP2Y0A41SK0F, 4-40 cm IR Sensor
pmic 45:5e1dd4117ed2 39 float ir_distance_mV = 0.0f; // define variable to store measurement
pmic 45:5e1dd4117ed2 40 AnalogIn ir_analog_in(PC_2); // create AnalogIn object to read in infrared distance sensor, 0...3.3V are mapped to 0...1
pmic 45:5e1dd4117ed2 41
pmic 45:5e1dd4117ed2 42 // 78:1, 100:1, ... Metal Gearmotor 20Dx44L mm 12V CB
pmic 45:5e1dd4117ed2 43 DigitalOut enable_motors(PB_15); // create DigitalOut object to enable dc motors
pmic 45:5e1dd4117ed2 44
pmic 45:5e1dd4117ed2 45 // create SpeedController objects, default parametrization is for 78.125:1 gear box
pmic 45:5e1dd4117ed2 46 FastPWM pwm_M1(PB_13); // motor M1 is closed-loop speed controlled (angle velocity)
pmic 45:5e1dd4117ed2 47 FastPWM pwm_M2(PA_9); // motor M2 is closed-loop speed controlled (angle velocity)
pmic 45:5e1dd4117ed2 48 EncoderCounter encoder_M1(PA_6, PC_7); // create encoder objects to read in the encoder counter values
pmic 45:5e1dd4117ed2 49 EncoderCounter encoder_M2(PB_6, PB_7);
pmic 45:5e1dd4117ed2 50 const float max_voltage = 12.0f; // define maximum voltage of battery packs, adjust this to 6.0f V if you only use one batterypack
pmic 45:5e1dd4117ed2 51 const float counts_per_turn = 20.0f * 78.125f; // define counts per turn at gearbox end: counts/turn * gearratio
pmic 45:5e1dd4117ed2 52 const float kn = 180.0f / 12.0f; // define motor constant in rpm per V
pmic 46:fd580fa68618 53 //const float k_gear = 100.0f / 78.125f; // define additional ratio in case you are using a dc motor with a different gear box, e.g. 100:1
pmic 46:fd580fa68618 54 //const float kp = 0.1f; // define custom kp, this is the default speed controller gain for gear box 78.125:1
pmic 44:340cdc4b6e47 55
pmic 46:fd580fa68618 56 SpeedController* speedControllers[1];
pmic 45:5e1dd4117ed2 57 speedControllers[0] = new SpeedController(counts_per_turn, kn, max_voltage, pwm_M1, encoder_M1);
pmic 46:fd580fa68618 58 //speedControllers[1] = new SpeedController(counts_per_turn, kn, max_voltage, pwm_M2, encoder_M2);
pmic 46:fd580fa68618 59 speedControllers[0]->setMaxAccelerationRPM(22.0f * max_voltage * kn * 0.05f);
pmic 46:fd580fa68618 60 //speedControllers[1]->setMaxAccelerationRPM(22.0f * max_voltage * kn * 0.1f);
pmic 46:fd580fa68618 61 PositionController* positionController = new PositionController(counts_per_turn, kn, max_voltage, pwm_M2, encoder_M2);
pmic 46:fd580fa68618 62 positionController->setMaxAccelerationRPM(22.0f * max_voltage * kn * 0.05f);
pmic 46:fd580fa68618 63 positionController->setMaxVelocityRPS(2.0f);
pmic 45:5e1dd4117ed2 64 //std::vector<SpeedController*> speedControllers;
pmic 45:5e1dd4117ed2 65 //speedControllers.push_back( new SpeedController(counts_per_turn, kn, max_voltage, pwm_M1, encoder_M1) );
pmic 45:5e1dd4117ed2 66 //speedControllers.push_back( new SpeedController(counts_per_turn, kn, max_voltage, pwm_M2, encoder_M2) );
pmic 45:5e1dd4117ed2 67
pmic 45:5e1dd4117ed2 68 // create SensorBar object for sparkfun line follower array
pmic 45:5e1dd4117ed2 69 I2C i2c(PB_9, PB_8);
pmic 45:5e1dd4117ed2 70 SensorBar sensor_bar(i2c, 0.1175f);
pmic 45:5e1dd4117ed2 71
pmic 45:5e1dd4117ed2 72 // robot kinematics
pmic 45:5e1dd4117ed2 73 const float r_wheel = 0.0358f / 2.0f;
pmic 45:5e1dd4117ed2 74 const float L_wheel = 0.143f;
pmic 45:5e1dd4117ed2 75 Eigen::Matrix2f Cwheel2robot; // transform wheel to robot
pmic 45:5e1dd4117ed2 76 Eigen::Matrix2f Crobot2wheel; // transform robot to wheel
pmic 45:5e1dd4117ed2 77 Eigen::Vector2f robot_coord; // contains v and w (robot translational and rotational velocities)
pmic 45:5e1dd4117ed2 78 Eigen::Vector2f wheel_speed; // w1 w2 (wheel speed)
pmic 46:fd580fa68618 79 Cwheel2robot << r_wheel / 2.0f, r_wheel / 2.0f,
pmic 46:fd580fa68618 80 r_wheel / L_wheel, -r_wheel / L_wheel;
pmic 45:5e1dd4117ed2 81 Crobot2wheel << 1.0f / r_wheel, L_wheel / (2.0f * r_wheel),
pmic 46:fd580fa68618 82 1.0f / r_wheel, -L_wheel / (2.0f * r_wheel);
pmic 45:5e1dd4117ed2 83 robot_coord.setZero();
pmic 45:5e1dd4117ed2 84 wheel_speed.setZero();
pmic 46:fd580fa68618 85
pmic 24:86f1a63e35a0 86 // attach button fall and rise functions to user button object
pmic 24:86f1a63e35a0 87 user_button.fall(&user_button_pressed_fcn);
pmic 24:86f1a63e35a0 88 user_button.rise(&user_button_released_fcn);
pmic 17:c19b471f05cb 89
pmic 29:d6f1ccf42a31 90 // start timer
pmic 24:86f1a63e35a0 91 main_task_timer.start();
pmic 6:e1fa1a2d7483 92
pmic 38:6d11788e14c0 93 // enable hardwaredriver dc motors: 0 -> disabled, 1 -> enabled
pmic 38:6d11788e14c0 94 enable_motors = 1;
pmic 6:e1fa1a2d7483 95
pmic 46:fd580fa68618 96
pmic 46:fd580fa68618 97 Motion motion;
pmic 46:fd580fa68618 98 motion.setProfileVelocity(10.0f);
pmic 46:fd580fa68618 99 motion.setProfileAcceleration(5.0f);
pmic 46:fd580fa68618 100 motion.setProfileDeceleration(5.0f);
pmic 46:fd580fa68618 101
pmic 24:86f1a63e35a0 102 while (true) { // this loop will run forever
pmic 6:e1fa1a2d7483 103
pmic 24:86f1a63e35a0 104 main_task_timer.reset();
pmic 6:e1fa1a2d7483 105
pmic 24:86f1a63e35a0 106 if (do_execute_main_task) {
pmic 34:702246639f02 107
pmic 42:b54a4f294aa9 108 // read SensorBar
pmic 43:5648b7083fe5 109 static float sensor_bar_avgAngleRad = 0.0f; // by making this static it will not be overwritten (only fist time set to zero)
pmic 42:b54a4f294aa9 110 if (sensor_bar.isAnyLedActive()) {
pmic 42:b54a4f294aa9 111 sensor_bar_avgAngleRad = sensor_bar.getAvgAngleRad();
pmic 42:b54a4f294aa9 112 }
pmic 42:b54a4f294aa9 113
pmic 45:5e1dd4117ed2 114 const static float Kp = 2.0f;
pmic 45:5e1dd4117ed2 115 const static float Kp_nl = 17.0f;
pmic 45:5e1dd4117ed2 116 robot_coord(1) = ang_cntrl_fcn(Kp, Kp_nl, sensor_bar_avgAngleRad);
pmic 42:b54a4f294aa9 117
pmic 43:5648b7083fe5 118 // nonlinear controllers version 1 (whatever came to my mind)
pmic 43:5648b7083fe5 119 /*
pmic 43:5648b7083fe5 120 const static float vel_max = 0.3374f; //0.10f;
pmic 43:5648b7083fe5 121 const static float vel_min = 0.00f; //0.02f;
pmic 43:5648b7083fe5 122 const static float ang_max = 27.0f * M_PI / 180.0f;
pmic 45:5e1dd4117ed2 123 robot_coord(0) = vel_cntrl_v1_fcn(vel_max, vel_min, ang_max, sensor_bar_avgAngleRad);
pmic 43:5648b7083fe5 124 */
pmic 43:5648b7083fe5 125
pmic 43:5648b7083fe5 126 // nonlinear controllers version 2 (one wheel always at full speed controller)
pmic 43:5648b7083fe5 127 ///*
pmic 45:5e1dd4117ed2 128 const static float wheel_speed_max = max_voltage * kn / 60.0f * 2.0f * M_PI;
pmic 45:5e1dd4117ed2 129 const static float b = L_wheel / (2.0f * r_wheel);
pmic 45:5e1dd4117ed2 130 robot_coord(0) = vel_cntrl_v2_fcn(wheel_speed_max, b, robot_coord(1), Cwheel2robot);
pmic 43:5648b7083fe5 131 //*/
pmic 43:5648b7083fe5 132
pmic 42:b54a4f294aa9 133 // transform to robot coordinates
pmic 42:b54a4f294aa9 134 wheel_speed = Crobot2wheel * robot_coord;
pmic 42:b54a4f294aa9 135
pmic 38:6d11788e14c0 136 // read analog input
pmic 38:6d11788e14c0 137 ir_distance_mV = 1.0e3f * ir_analog_in.read() * 3.3f;
pmic 38:6d11788e14c0 138
pmic 46:fd580fa68618 139 //speedControllers[0]->setDesiredSpeedRPS(wheel_speed(0) / (2.0f * M_PI)); // set a desired speed for speed controlled dc motors M1
pmic 46:fd580fa68618 140 //speedControllers[1]->setDesiredSpeedRPS(wheel_speed(1) / (2.0f * M_PI)); // set a desired speed for speed controlled dc motors M2
pmic 46:fd580fa68618 141 speedControllers[0]->setDesiredSpeedRPS(speed);
pmic 46:fd580fa68618 142 //speedControllers[1]->setDesiredSpeedRPS(speed);
pmic 46:fd580fa68618 143 positionController->setDesiredRotation(speed);
pmic 34:702246639f02 144
pmic 1:93d997d6b232 145 } else {
pmic 6:e1fa1a2d7483 146
pmic 38:6d11788e14c0 147 ir_distance_mV = 0.0f;
pmic 38:6d11788e14c0 148
pmic 46:fd580fa68618 149 speedControllers[0]->setDesiredSpeedRPS(speed);
pmic 46:fd580fa68618 150 //speedControllers[1]->setDesiredSpeedRPS(speed);
pmic 46:fd580fa68618 151 positionController->setDesiredRotation(speed);
pmic 46:fd580fa68618 152
pmic 46:fd580fa68618 153
pmic 46:fd580fa68618 154
pmic 33:cff70742569d 155 }
pmic 6:e1fa1a2d7483 156
pmic 24:86f1a63e35a0 157 user_led = !user_led;
pmic 24:86f1a63e35a0 158
pmic 24:86f1a63e35a0 159 // do only output via serial what's really necessary (this makes your code slow)
pmic 46:fd580fa68618 160 //printf("%d, %d\r\n", sensor_bar_raw_value_time_ms, sensor_bar_position_time_ms);
pmic 46:fd580fa68618 161 //printf("%f, %f\r\n", speedControllers[0]->getSpeedRPS(), speedControllers[1]->getSpeedRPS());
pmic 46:fd580fa68618 162
pmic 46:fd580fa68618 163 motion.incrementToPosition(motionspeed, static_cast<float>(main_task_period_ms) * 1.0e-3f);
pmic 46:fd580fa68618 164 float motionpositionactual = motion.getPosition();
pmic 46:fd580fa68618 165 float motionspeedactual = motion.getVelocity();
pmic 46:fd580fa68618 166 printf("%f, %f, %f, %f, %f\r\n", speedControllers[0]->getSpeedRPS(), positionController->getRotation(), positionController->getSpeedRPS(), motionpositionactual, motionspeedactual);
pmic 17:c19b471f05cb 167
pmic 24:86f1a63e35a0 168 // read timer and make the main thread sleep for the remaining time span (non blocking)
pmic 24:86f1a63e35a0 169 int main_task_elapsed_time_ms = std::chrono::duration_cast<std::chrono::milliseconds>(main_task_timer.elapsed_time()).count();
pmic 24:86f1a63e35a0 170 thread_sleep_for(main_task_period_ms - main_task_elapsed_time_ms);
pmic 1:93d997d6b232 171 }
pmic 1:93d997d6b232 172 }
pmic 6:e1fa1a2d7483 173
pmic 24:86f1a63e35a0 174 void user_button_pressed_fcn()
pmic 25:ea1d6e27c895 175 {
pmic 26:28693b369945 176 user_button_timer.start();
pmic 6:e1fa1a2d7483 177 user_button_timer.reset();
pmic 6:e1fa1a2d7483 178 }
pmic 6:e1fa1a2d7483 179
pmic 24:86f1a63e35a0 180 void user_button_released_fcn()
pmic 6:e1fa1a2d7483 181 {
pmic 24:86f1a63e35a0 182 // read timer and toggle do_execute_main_task if the button was pressed longer than the below specified time
pmic 24:86f1a63e35a0 183 int user_button_elapsed_time_ms = std::chrono::duration_cast<std::chrono::milliseconds>(user_button_timer.elapsed_time()).count();
pmic 6:e1fa1a2d7483 184 user_button_timer.stop();
pmic 24:86f1a63e35a0 185 if (user_button_elapsed_time_ms > 200) {
pmic 24:86f1a63e35a0 186 do_execute_main_task = !do_execute_main_task;
pmic 46:fd580fa68618 187 if(do_execute_main_task) {
pmic 46:fd580fa68618 188 motionspeed = 12.0f;
pmic 46:fd580fa68618 189 speed = 2.7f;
pmic 46:fd580fa68618 190 } else {
pmic 46:fd580fa68618 191 motionspeed = -12.0f;
pmic 46:fd580fa68618 192 speed = -2.7f;
pmic 46:fd580fa68618 193 }
pmic 8:9bb806a7f585 194 }
pmic 42:b54a4f294aa9 195 }
pmic 42:b54a4f294aa9 196
pmic 45:5e1dd4117ed2 197 float ang_cntrl_fcn(const float& Kp, const float& Kp_nl, const float& angle)
pmic 43:5648b7083fe5 198 {
pmic 45:5e1dd4117ed2 199 static float retval = 0.0f;
pmic 43:5648b7083fe5 200 if (angle > 0) {
pmic 43:5648b7083fe5 201 retval = Kp * angle + Kp_nl * angle * angle;
pmic 45:5e1dd4117ed2 202 } else if (angle <= 0) {
pmic 43:5648b7083fe5 203 retval = Kp * angle - Kp_nl * angle * angle;
pmic 43:5648b7083fe5 204 }
pmic 43:5648b7083fe5 205 return retval;
pmic 43:5648b7083fe5 206 }
pmic 43:5648b7083fe5 207
pmic 45:5e1dd4117ed2 208 float vel_cntrl_v1_fcn(const float& vel_max, const float& vel_min, const float& ang_max, const float& angle)
pmic 42:b54a4f294aa9 209 {
pmic 42:b54a4f294aa9 210 const static float gain = (vel_min - vel_max) / ang_max;
pmic 42:b54a4f294aa9 211 const static float offset = vel_max;
pmic 43:5648b7083fe5 212 return gain * fabs(angle) + offset;
pmic 42:b54a4f294aa9 213 }
pmic 42:b54a4f294aa9 214
pmic 45:5e1dd4117ed2 215 float vel_cntrl_v2_fcn(const float& wheel_speed_max, const float& b, const float& robot_omega, const Eigen::Matrix2f& Cwheel2robot)
pmic 42:b54a4f294aa9 216 {
pmic 43:5648b7083fe5 217 static Eigen::Matrix<float, 2, 2> _wheel_speed;
pmic 43:5648b7083fe5 218 static Eigen::Matrix<float, 2, 2> _robot_coord;
pmic 43:5648b7083fe5 219 if (robot_omega > 0) {
pmic 43:5648b7083fe5 220 _wheel_speed(0) = wheel_speed_max;
pmic 43:5648b7083fe5 221 _wheel_speed(1) = wheel_speed_max - 2*b*robot_omega;
pmic 43:5648b7083fe5 222 } else {
pmic 43:5648b7083fe5 223 _wheel_speed(0) = wheel_speed_max + 2*b*robot_omega;
pmic 43:5648b7083fe5 224 _wheel_speed(1) = wheel_speed_max;
pmic 42:b54a4f294aa9 225 }
pmic 43:5648b7083fe5 226 _robot_coord = Cwheel2robot * _wheel_speed;
pmic 43:5648b7083fe5 227 return _robot_coord(0);
pmic 6:e1fa1a2d7483 228 }