Michael Ernst Peter / Mbed OS PM2_Example_Line_Follower

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Dependencies:   PM2_Libary Eigen

main.cpp@53:155c309f7d75, 2022-06-22 (annotated)

Committer:
pmic
Date:
Wed Jun 22 17:44:18 2022 +0200
Revision:
53:155c309f7d75
Parent:
52:60a710ecc162 
Updated versioning macro and updated libaries

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 33:cff70742569d 3
pmic 17:c19b471f05cb 4 #include "PM2_Libary.h"
pmic 40:eb7f8dce5787 5 #include "Eigen/Dense.h"
pmic 6:e1fa1a2d7483 6
pmic 53:155c309f7d75 7 #define NEW_PES_BOARD_VERSION
pmic 53:155c309f7d75 8
pmic 53:155c309f7d75 9 #ifdef NEW_PES_BOARD_VERSION
pmic 53:155c309f7d75 10 #define PN_enable_Motors PB_15
pmic 53:155c309f7d75 11 #define PN_pwm_M1 PB_13
pmic 53:155c309f7d75 12 #define PN_pwm_M2 PA_9
pmic 53:155c309f7d75 13 #define PN_encoder_M1_A PA_6
pmic 53:155c309f7d75 14 #define PN_encoder_M1_B PC_7
pmic 53:155c309f7d75 15 #define PN_encoder_M2_A PB_6
pmic 53:155c309f7d75 16 #define PN_encoder_M2_B PB_7
pmic 53:155c309f7d75 17 #else
pmic 53:155c309f7d75 18 #define PN_enable_Motors PB_2
pmic 53:155c309f7d75 19 #define PN_pwm_M1 PA_8
pmic 53:155c309f7d75 20 #define PN_pwm_M2 PA_9
pmic 53:155c309f7d75 21 #define PN_encoder_M1_A PB_6
pmic 53:155c309f7d75 22 #define PN_encoder_M1_B PB_7
pmic 53:155c309f7d75 23 #define PN_encoder_M2_A PA_6
pmic 53:155c309f7d75 24 #define PN_encoder_M2_B PC_7
pmic 53:155c309f7d75 25 #endif
pmic 53:155c309f7d75 26
pmic 53:155c309f7d75 27 #define M_PI 3.14159265358979323846 // number pi
pmic 33:cff70742569d 28
pmic 24:86f1a63e35a0 29 // logical variable main task
pmic 24:86f1a63e35a0 30 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 31
pmic 24:86f1a63e35a0 32 // user button on nucleo board
pmic 24:86f1a63e35a0 33 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 34 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 35 void user_button_pressed_fcn(); // custom functions which gets executed when user button gets pressed and released, definition below
pmic 24:86f1a63e35a0 36 void user_button_released_fcn();
pmic 6:e1fa1a2d7483 37
pmic 45:5e1dd4117ed2 38 // controller functions
pmic 45:5e1dd4117ed2 39 float ang_cntrl_fcn(const float& Kp, const float& Kp_nl, const float& angle);
pmic 45:5e1dd4117ed2 40 float vel_cntrl_v1_fcn(const float& vel_max, const float& vel_min, const float& ang_max, const float& angle);
pmic 45:5e1dd4117ed2 41 float vel_cntrl_v2_fcn(const float& wheel_speed_max, const float& b, const float& robot_omega, const Eigen::Matrix2f& Cwheel2robot);
pmic 38:6d11788e14c0 42
pmic 1:93d997d6b232 43 int main()
pmic 46:fd580fa68618 44 {
pmic 45:5e1dd4117ed2 45 // while loop gets executed every main_task_period_ms milliseconds
pmic 45:5e1dd4117ed2 46 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 48:3ae406d7554a 47 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 48
pmic 45:5e1dd4117ed2 49 // led on nucleo board
pmic 45:5e1dd4117ed2 50 DigitalOut user_led(LED1); // create DigitalOut object to command user led
pmic 45:5e1dd4117ed2 51
pmic 45:5e1dd4117ed2 52 // Sharp GP2Y0A41SK0F, 4-40 cm IR Sensor
pmic 45:5e1dd4117ed2 53 float ir_distance_mV = 0.0f; // define variable to store measurement
pmic 45:5e1dd4117ed2 54 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 55
pmic 45:5e1dd4117ed2 56 // 78:1, 100:1, ... Metal Gearmotor 20Dx44L mm 12V CB
pmic 53:155c309f7d75 57 DigitalOut enable_motors(PN_enable_Motors); // create DigitalOut object to enable dc motors
pmic 45:5e1dd4117ed2 58
pmic 50:fec2ffc2a443 59 // create SpeedController objects
pmic 53:155c309f7d75 60 FastPWM pwm_M1(PN_pwm_M1); // motor M1 is closed-loop speed controlled (angle velocity)
pmic 53:155c309f7d75 61 FastPWM pwm_M2(PN_pwm_M2); // motor M2 is closed-loop speed controlled (angle velocity)
pmic 53:155c309f7d75 62 EncoderCounter encoder_M1(PN_encoder_M1_A, PN_encoder_M1_B); // create encoder objects to read in the encoder counter values
pmic 53:155c309f7d75 63 EncoderCounter encoder_M2(PN_encoder_M2_A, PN_encoder_M2_B);
pmic 45:5e1dd4117ed2 64 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 65 const float counts_per_turn = 20.0f * 78.125f; // define counts per turn at gearbox end: counts/turn * gearratio
pmic 45:5e1dd4117ed2 66 const float kn = 180.0f / 12.0f; // define motor constant in rpm per V
pmic 50:fec2ffc2a443 67
pmic 52:60a710ecc162 68 // create SpeedController objects
pmic 48:3ae406d7554a 69 SpeedController* speedControllers[2];
pmic 45:5e1dd4117ed2 70 speedControllers[0] = new SpeedController(counts_per_turn, kn, max_voltage, pwm_M1, encoder_M1);
pmic 48:3ae406d7554a 71 speedControllers[1] = new SpeedController(counts_per_turn, kn, max_voltage, pwm_M2, encoder_M2);
pmic 51:b27f2beaf7b3 72 //speedControllers[0]->setMaxAccelerationRPS(999.0f); // big number, so it is no doing anything
pmic 51:b27f2beaf7b3 73 //speedControllers[1]->setMaxAccelerationRPS(999.0f); // big number, so it is no doing anything
pmic 51:b27f2beaf7b3 74
pmic 45:5e1dd4117ed2 75 // create SensorBar object for sparkfun line follower array
pmic 45:5e1dd4117ed2 76 I2C i2c(PB_9, PB_8);
pmic 48:3ae406d7554a 77 SensorBar sensor_bar(i2c, 0.1175f); // second input argument is distance from bar to wheel axis
pmic 45:5e1dd4117ed2 78
pmic 45:5e1dd4117ed2 79 // robot kinematics
pmic 51:b27f2beaf7b3 80 const float r_wheel = 0.0358f / 2.0f; // wheel radius
pmic 51:b27f2beaf7b3 81 const float L_wheel = 0.143f; // distance from wheel to wheel
pmic 45:5e1dd4117ed2 82 Eigen::Matrix2f Cwheel2robot; // transform wheel to robot
pmic 50:fec2ffc2a443 83 //Eigen::Matrix2f Crobot2wheel; // transform robot to wheel
pmic 50:fec2ffc2a443 84 Cwheel2robot << r_wheel / 2.0f , r_wheel / 2.0f ,
pmic 50:fec2ffc2a443 85 r_wheel / L_wheel, -r_wheel / L_wheel;
pmic 50:fec2ffc2a443 86 //Crobot2wheel << 1.0f / r_wheel, L_wheel / (2.0f * r_wheel),
pmic 50:fec2ffc2a443 87 // 1.0f / r_wheel, -L_wheel / (2.0f * r_wheel);
pmic 48:3ae406d7554a 88 Eigen::Vector2f robot_coord; // contains v and w (robot translational and rotational velocities)
pmic 50:fec2ffc2a443 89 Eigen::Vector2f wheel_speed; // w1 w2 (wheel speed)
pmic 45:5e1dd4117ed2 90 robot_coord.setZero();
pmic 45:5e1dd4117ed2 91 wheel_speed.setZero();
pmic 46:fd580fa68618 92
pmic 24:86f1a63e35a0 93 // attach button fall and rise functions to user button object
pmic 24:86f1a63e35a0 94 user_button.fall(&user_button_pressed_fcn);
pmic 24:86f1a63e35a0 95 user_button.rise(&user_button_released_fcn);
pmic 17:c19b471f05cb 96
pmic 29:d6f1ccf42a31 97 // start timer
pmic 24:86f1a63e35a0 98 main_task_timer.start();
pmic 6:e1fa1a2d7483 99
pmic 24:86f1a63e35a0 100 while (true) { // this loop will run forever
pmic 6:e1fa1a2d7483 101
pmic 24:86f1a63e35a0 102 main_task_timer.reset();
pmic 6:e1fa1a2d7483 103
pmic 24:86f1a63e35a0 104 if (do_execute_main_task) {
pmic 34:702246639f02 105
pmic 48:3ae406d7554a 106 // enable hardwaredriver dc motors: 0 -> disabled, 1 -> enabled
pmic 48:3ae406d7554a 107 enable_motors = 1;
pmic 47:5ce234723e3a 108
pmic 42:b54a4f294aa9 109 // read SensorBar
pmic 43:5648b7083fe5 110 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 111 if (sensor_bar.isAnyLedActive()) {
pmic 42:b54a4f294aa9 112 sensor_bar_avgAngleRad = sensor_bar.getAvgAngleRad();
pmic 42:b54a4f294aa9 113 }
pmic 42:b54a4f294aa9 114
pmic 48:3ae406d7554a 115 const static float Kp = 2.0f; // by making this const static it will not be overwritten and only initiliazed once
pmic 45:5e1dd4117ed2 116 const static float Kp_nl = 17.0f;
pmic 45:5e1dd4117ed2 117 robot_coord(1) = ang_cntrl_fcn(Kp, Kp_nl, sensor_bar_avgAngleRad);
pmic 42:b54a4f294aa9 118
pmic 43:5648b7083fe5 119 // nonlinear controllers version 1 (whatever came to my mind)
pmic 43:5648b7083fe5 120 /*
pmic 43:5648b7083fe5 121 const static float vel_max = 0.3374f; //0.10f;
pmic 43:5648b7083fe5 122 const static float vel_min = 0.00f; //0.02f;
pmic 43:5648b7083fe5 123 const static float ang_max = 27.0f * M_PI / 180.0f;
pmic 45:5e1dd4117ed2 124 robot_coord(0) = vel_cntrl_v1_fcn(vel_max, vel_min, ang_max, sensor_bar_avgAngleRad);
pmic 43:5648b7083fe5 125 */
pmic 43:5648b7083fe5 126
pmic 43:5648b7083fe5 127 // nonlinear controllers version 2 (one wheel always at full speed controller)
pmic 43:5648b7083fe5 128 ///*
pmic 45:5e1dd4117ed2 129 const static float wheel_speed_max = max_voltage * kn / 60.0f * 2.0f * M_PI;
pmic 45:5e1dd4117ed2 130 const static float b = L_wheel / (2.0f * r_wheel);
pmic 45:5e1dd4117ed2 131 robot_coord(0) = vel_cntrl_v2_fcn(wheel_speed_max, b, robot_coord(1), Cwheel2robot);
pmic 43:5648b7083fe5 132 //*/
pmic 43:5648b7083fe5 133
pmic 50:fec2ffc2a443 134 // transform robot coordinates to wheel speed
pmic 50:fec2ffc2a443 135 wheel_speed = Cwheel2robot.inverse() * robot_coord;
pmic 42:b54a4f294aa9 136
pmic 38:6d11788e14c0 137 // read analog input
pmic 38:6d11788e14c0 138 ir_distance_mV = 1.0e3f * ir_analog_in.read() * 3.3f;
pmic 38:6d11788e14c0 139
pmic 50:fec2ffc2a443 140 // command speedController objects
pmic 48:3ae406d7554a 141 speedControllers[0]->setDesiredSpeedRPS(wheel_speed(0) / (2.0f * M_PI)); // set a desired speed for speed controlled dc motors M1
pmic 48:3ae406d7554a 142 speedControllers[1]->setDesiredSpeedRPS(wheel_speed(1) / (2.0f * M_PI)); // set a desired speed for speed controlled dc motors M2
pmic 34:702246639f02 143
pmic 1:93d997d6b232 144 } else {
pmic 6:e1fa1a2d7483 145
pmic 48:3ae406d7554a 146 enable_motors = 0;
pmic 48:3ae406d7554a 147
pmic 38:6d11788e14c0 148 ir_distance_mV = 0.0f;
pmic 38:6d11788e14c0 149
pmic 48:3ae406d7554a 150 speedControllers[0]->setDesiredSpeedRPS(0.0f);
pmic 48:3ae406d7554a 151 speedControllers[1]->setDesiredSpeedRPS(0.0f);
pmic 46:fd580fa68618 152
pmic 33:cff70742569d 153 }
pmic 6:e1fa1a2d7483 154
pmic 24:86f1a63e35a0 155 user_led = !user_led;
pmic 24:86f1a63e35a0 156
pmic 24:86f1a63e35a0 157 // do only output via serial what's really necessary (this makes your code slow)
pmic 53:155c309f7d75 158 printf("%f, %f, %f\r\n", speedControllers[0]->getSpeedRPS(), speedControllers[1]->getSpeedRPS(), sensor_bar.getAvgAngleRad() * 180.0f / M_PI);
pmic 46:fd580fa68618 159
pmic 24:86f1a63e35a0 160 // read timer and make the main thread sleep for the remaining time span (non blocking)
pmic 24:86f1a63e35a0 161 int main_task_elapsed_time_ms = std::chrono::duration_cast<std::chrono::milliseconds>(main_task_timer.elapsed_time()).count();
pmic 24:86f1a63e35a0 162 thread_sleep_for(main_task_period_ms - main_task_elapsed_time_ms);
pmic 1:93d997d6b232 163 }
pmic 1:93d997d6b232 164 }
pmic 6:e1fa1a2d7483 165
pmic 24:86f1a63e35a0 166 void user_button_pressed_fcn()
pmic 25:ea1d6e27c895 167 {
pmic 26:28693b369945 168 user_button_timer.start();
pmic 6:e1fa1a2d7483 169 user_button_timer.reset();
pmic 6:e1fa1a2d7483 170 }
pmic 6:e1fa1a2d7483 171
pmic 24:86f1a63e35a0 172 void user_button_released_fcn()
pmic 6:e1fa1a2d7483 173 {
pmic 24:86f1a63e35a0 174 // read timer and toggle do_execute_main_task if the button was pressed longer than the below specified time
pmic 24:86f1a63e35a0 175 int user_button_elapsed_time_ms = std::chrono::duration_cast<std::chrono::milliseconds>(user_button_timer.elapsed_time()).count();
pmic 6:e1fa1a2d7483 176 user_button_timer.stop();
pmic 24:86f1a63e35a0 177 if (user_button_elapsed_time_ms > 200) {
pmic 24:86f1a63e35a0 178 do_execute_main_task = !do_execute_main_task;
pmic 8:9bb806a7f585 179 }
pmic 42:b54a4f294aa9 180 }
pmic 42:b54a4f294aa9 181
pmic 45:5e1dd4117ed2 182 float ang_cntrl_fcn(const float& Kp, const float& Kp_nl, const float& angle)
pmic 43:5648b7083fe5 183 {
pmic 45:5e1dd4117ed2 184 static float retval = 0.0f;
pmic 43:5648b7083fe5 185 if (angle > 0) {
pmic 43:5648b7083fe5 186 retval = Kp * angle + Kp_nl * angle * angle;
pmic 45:5e1dd4117ed2 187 } else if (angle <= 0) {
pmic 43:5648b7083fe5 188 retval = Kp * angle - Kp_nl * angle * angle;
pmic 43:5648b7083fe5 189 }
pmic 43:5648b7083fe5 190 return retval;
pmic 43:5648b7083fe5 191 }
pmic 43:5648b7083fe5 192
pmic 45:5e1dd4117ed2 193 float vel_cntrl_v1_fcn(const float& vel_max, const float& vel_min, const float& ang_max, const float& angle)
pmic 42:b54a4f294aa9 194 {
pmic 42:b54a4f294aa9 195 const static float gain = (vel_min - vel_max) / ang_max;
pmic 42:b54a4f294aa9 196 const static float offset = vel_max;
pmic 43:5648b7083fe5 197 return gain * fabs(angle) + offset;
pmic 42:b54a4f294aa9 198 }
pmic 42:b54a4f294aa9 199
pmic 45:5e1dd4117ed2 200 float vel_cntrl_v2_fcn(const float& wheel_speed_max, const float& b, const float& robot_omega, const Eigen::Matrix2f& Cwheel2robot)
pmic 42:b54a4f294aa9 201 {
pmic 43:5648b7083fe5 202 static Eigen::Matrix<float, 2, 2> _wheel_speed;
pmic 43:5648b7083fe5 203 static Eigen::Matrix<float, 2, 2> _robot_coord;
pmic 43:5648b7083fe5 204 if (robot_omega > 0) {
pmic 43:5648b7083fe5 205 _wheel_speed(0) = wheel_speed_max;
pmic 43:5648b7083fe5 206 _wheel_speed(1) = wheel_speed_max - 2*b*robot_omega;
pmic 43:5648b7083fe5 207 } else {
pmic 43:5648b7083fe5 208 _wheel_speed(0) = wheel_speed_max + 2*b*robot_omega;
pmic 43:5648b7083fe5 209 _wheel_speed(1) = wheel_speed_max;
pmic 42:b54a4f294aa9 210 }
pmic 43:5648b7083fe5 211 _robot_coord = Cwheel2robot * _wheel_speed;
pmic 43:5648b7083fe5 212 return _robot_coord(0);
pmic 6:e1fa1a2d7483 213 }