Cole Helgeson / Mbed OS PM2_Example_Summer_School

Workshop 1

Dependencies:   PM2_Libary Eigen

main.cpp@41:8a63b01edd7e, 2022-05-17 (annotated)

Committer:
pmic
Date:
Tue May 17 15:42:29 2022 +0200
Revision:
41:8a63b01edd7e
Parent:
40:7e6b7aec3947
Child:
42:883d16a5d59e
This is the example project for the students

Who changed what in which revision?

UserRevisionLine numberNew contents of line
pmic 36:8c75783c1eca 1 #include <mbed.h>
pmic 36:8c75783c1eca 2
pmic 17:c19b471f05cb 3 #include "PM2_Libary.h"
pmic 36:8c75783c1eca 4 #include "Eigen/Dense.h"
pmic 36:8c75783c1eca 5
pmic 36:8c75783c1eca 6 # define M_PI 3.14159265358979323846 // number pi
pmic 6:e1fa1a2d7483 7
pmic 24:86f1a63e35a0 8 // logical variable main task
pmic 24:86f1a63e35a0 9 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 10
pmic 24:86f1a63e35a0 11 // user button on nucleo board
pmic 24:86f1a63e35a0 12 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 13 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 14 void user_button_pressed_fcn(); // custom functions which gets executed when user button gets pressed and released, definition below
pmic 24:86f1a63e35a0 15 void user_button_released_fcn();
pmic 6:e1fa1a2d7483 16
pmic 41:8a63b01edd7e 17 float ir_distance_mV2cm(float ir_distance_cm);
pmic 41:8a63b01edd7e 18
pmic 1:93d997d6b232 19 int main()
pmic 23:26b3a25fc637 20 {
pmic 36:8c75783c1eca 21 // while loop gets executed every main_task_period_ms milliseconds
pmic 41:8a63b01edd7e 22 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 36:8c75783c1eca 23 Timer main_task_timer; // create Timer object which we use to run the main task every main task period time in ms
pmic 36:8c75783c1eca 24
pmic 40:7e6b7aec3947 25 // a coutner
pmic 40:7e6b7aec3947 26 uint32_t main_task_cntr = 0;
pmic 40:7e6b7aec3947 27
pmic 36:8c75783c1eca 28 // led on nucleo board
pmic 36:8c75783c1eca 29 DigitalOut user_led(LED1); // create DigitalOut object to command user led
pmic 36:8c75783c1eca 30
pmic 36:8c75783c1eca 31 // Sharp GP2Y0A41SK0F, 4-40 cm IR Sensor
pmic 36:8c75783c1eca 32 float ir_distance_mV = 0.0f; // define variable to store measurement
pmic 41:8a63b01edd7e 33 float ir_distance_cm = 0.0f; // compensated sensor value in cm
pmic 36:8c75783c1eca 34 AnalogIn ir_analog_in(PC_2); // create AnalogIn object to read in infrared distance sensor, 0...3.3V are mapped to 0...1
pmic 36:8c75783c1eca 35
pmic 40:7e6b7aec3947 36 // create SensorBar object for sparkfun line follower array, only use this if it is connected (blocking your code if not)
pmic 40:7e6b7aec3947 37 float sensor_bar_avgAngleRad = 0.0f;
pmic 40:7e6b7aec3947 38 I2C i2c(PB_9, PB_8);
pmic 40:7e6b7aec3947 39 //SensorBar sensor_bar(i2c, 0.1175f); // second input argument is distance from bar to wheel axis
pmic 40:7e6b7aec3947 40
pmic 36:8c75783c1eca 41 // 78:1, 100:1, ... Metal Gearmotor 20Dx44L mm 12V CB
pmic 36:8c75783c1eca 42 DigitalOut enable_motors(PB_15); // create DigitalOut object to enable dc motors
pmic 36:8c75783c1eca 43
pmic 40:7e6b7aec3947 44 FastPWM pwm_M1(PB_13); // motor M1 is closed-loop speed controlled (angle velocity)
pmic 40:7e6b7aec3947 45 FastPWM pwm_M2(PA_9); // motor M2 is closed-loop position controlled (angle controlled)
pmic 36:8c75783c1eca 46
pmic 36:8c75783c1eca 47 EncoderCounter encoder_M1(PA_6, PC_7); // create encoder objects to read in the encoder counter values
pmic 36:8c75783c1eca 48 EncoderCounter encoder_M2(PB_6, PB_7);
pmic 36:8c75783c1eca 49
pmic 36:8c75783c1eca 50 // create SpeedController and PositionController objects, default parametrization is for 78.125:1 gear box
pmic 36:8c75783c1eca 51 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 36:8c75783c1eca 52 const float counts_per_turn = 20.0f * 78.125f; // define counts per turn at gearbox end: counts/turn * gearratio
pmic 36:8c75783c1eca 53 const float kn = 180.0f / 12.0f; // define motor constant in rpm per V
pmic 40:7e6b7aec3947 54 //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 40:7e6b7aec3947 55 //const float kp = 0.1f; // define custom kp, this is the default speed controller gain for gear box 78.125:1
pmic 36:8c75783c1eca 56
pmic 40:7e6b7aec3947 57 SpeedController speedController_M1(counts_per_turn, kn, max_voltage, pwm_M1, encoder_M1); // default 78.125:1 gear box with default contoller parameters
pmic 40:7e6b7aec3947 58 //SpeedController speedController_M1(counts_per_turn * k_gear, kn / k_gear, max_voltage, pwm_M1, encoder_M1); // parameters adjusted to 100:1 gear
pmic 36:8c75783c1eca 59
pmic 40:7e6b7aec3947 60 PositionController positionController_M2(counts_per_turn, kn, max_voltage, pwm_M2, encoder_M2); // default 78.125:1 gear with default contoller parameters
pmic 40:7e6b7aec3947 61 //PositionController positionController_M2(counts_per_turn * k_gear, kn / k_gear, max_voltage, pwm_M2, encoder_M2); // parameters adjusted to 100:1 gear, we need a different speed controller gain here
pmic 40:7e6b7aec3947 62 //positionController_M2.setSpeedCntrlGain(kp * k_gear);
pmic 40:7e6b7aec3947 63 // define maximum speed that the position controller is changig the speed, has to be smaller or equal to kn * max_voltage
pmic 40:7e6b7aec3947 64 float max_speed_rps = 0.5f;
pmic 40:7e6b7aec3947 65 positionController_M2.setMaxVelocityRPS(max_speed_rps);
pmic 36:8c75783c1eca 66
pmic 24:86f1a63e35a0 67 // attach button fall and rise functions to user button object
pmic 24:86f1a63e35a0 68 user_button.fall(&user_button_pressed_fcn);
pmic 24:86f1a63e35a0 69 user_button.rise(&user_button_released_fcn);
pmic 17:c19b471f05cb 70
pmic 29:d6f1ccf42a31 71 // start timer
pmic 24:86f1a63e35a0 72 main_task_timer.start();
pmic 6:e1fa1a2d7483 73
pmic 24:86f1a63e35a0 74 // enable hardwaredriver dc motors: 0 -> disabled, 1 -> enabled
pmic 10:c5d85e35758c 75 enable_motors = 1;
pmic 17:c19b471f05cb 76
pmic 24:86f1a63e35a0 77 while (true) { // this loop will run forever
pmic 6:e1fa1a2d7483 78
pmic 24:86f1a63e35a0 79 main_task_timer.reset();
pmic 40:7e6b7aec3947 80
pmic 40:7e6b7aec3947 81 // read analog input
pmic 40:7e6b7aec3947 82 ir_distance_mV = 1.0e3f * ir_analog_in.read() * 3.3f;
pmic 41:8a63b01edd7e 83 ir_distance_cm = ir_distance_mV2cm(ir_distance_mV);
pmic 40:7e6b7aec3947 84
pmic 40:7e6b7aec3947 85 // read SensorBar, only use this if it is connected (blocking your code if not)
pmic 40:7e6b7aec3947 86 //if (sensor_bar.isAnyLedActive()) {
pmic 40:7e6b7aec3947 87 // sensor_bar_avgAngleRad = sensor_bar.getAvgAngleRad();
pmic 40:7e6b7aec3947 88 //}
pmic 6:e1fa1a2d7483 89
pmic 24:86f1a63e35a0 90 if (do_execute_main_task) {
pmic 17:c19b471f05cb 91
pmic 40:7e6b7aec3947 92 speedController_M1.setDesiredSpeedRPS(0.5f);
pmic 40:7e6b7aec3947 93 positionController_M2.setDesiredRotation(1.5f);
pmic 9:f10b974d01e0 94
pmic 1:93d997d6b232 95 } else {
pmic 6:e1fa1a2d7483 96
pmic 40:7e6b7aec3947 97 speedController_M1.setDesiredSpeedRPS(0.0f);
pmic 40:7e6b7aec3947 98 positionController_M2.setDesiredRotation(0.0f);
pmic 40:7e6b7aec3947 99
pmic 1:93d997d6b232 100 }
pmic 6:e1fa1a2d7483 101
pmic 41:8a63b01edd7e 102 // user_led is switching its state every second
pmic 41:8a63b01edd7e 103 if ( (main_task_cntr%(1000 / main_task_period_ms) == 0) && (main_task_cntr!=0) ) {
pmic 40:7e6b7aec3947 104 user_led = !user_led;
pmic 40:7e6b7aec3947 105 }
pmic 40:7e6b7aec3947 106 main_task_cntr++;
pmic 40:7e6b7aec3947 107
pmic 24:86f1a63e35a0 108 // do only output via serial what's really necessary (this makes your code slow)
pmic 41:8a63b01edd7e 109 /*
pmic 41:8a63b01edd7e 110 printf("IR sensor (mV): %3.3f, IR sensor (cm): %3.3f, SensorBar angle (rad): %3.3f, Speed M1 (rps) %3.3f, Position M2 (rot): %3.3f\r\n",
pmic 24:86f1a63e35a0 111 ir_distance_mV,
pmic 41:8a63b01edd7e 112 ir_distance_cm,
pmic 40:7e6b7aec3947 113 sensor_bar_avgAngleRad,
pmic 40:7e6b7aec3947 114 speedController_M1.getSpeedRPS(),
pmic 40:7e6b7aec3947 115 positionController_M2.getRotation());
pmic 41:8a63b01edd7e 116 */
pmic 17:c19b471f05cb 117
pmic 24:86f1a63e35a0 118 // read timer and make the main thread sleep for the remaining time span (non blocking)
pmic 24:86f1a63e35a0 119 int main_task_elapsed_time_ms = std::chrono::duration_cast<std::chrono::milliseconds>(main_task_timer.elapsed_time()).count();
pmic 24:86f1a63e35a0 120 thread_sleep_for(main_task_period_ms - main_task_elapsed_time_ms);
pmic 1:93d997d6b232 121 }
pmic 1:93d997d6b232 122 }
pmic 6:e1fa1a2d7483 123
pmic 24:86f1a63e35a0 124 void user_button_pressed_fcn()
pmic 25:ea1d6e27c895 125 {
pmic 26:28693b369945 126 user_button_timer.start();
pmic 6:e1fa1a2d7483 127 user_button_timer.reset();
pmic 6:e1fa1a2d7483 128 }
pmic 6:e1fa1a2d7483 129
pmic 24:86f1a63e35a0 130 void user_button_released_fcn()
pmic 6:e1fa1a2d7483 131 {
pmic 24:86f1a63e35a0 132 // read timer and toggle do_execute_main_task if the button was pressed longer than the below specified time
pmic 24:86f1a63e35a0 133 int user_button_elapsed_time_ms = std::chrono::duration_cast<std::chrono::milliseconds>(user_button_timer.elapsed_time()).count();
pmic 6:e1fa1a2d7483 134 user_button_timer.stop();
pmic 24:86f1a63e35a0 135 if (user_button_elapsed_time_ms > 200) {
pmic 24:86f1a63e35a0 136 do_execute_main_task = !do_execute_main_task;
pmic 8:9bb806a7f585 137 }
pmic 41:8a63b01edd7e 138 }
pmic 41:8a63b01edd7e 139
pmic 41:8a63b01edd7e 140 float ir_distance_mV2cm(float ir_distance_cm)
pmic 41:8a63b01edd7e 141 {
pmic 41:8a63b01edd7e 142 // defining these variables static makes them persistent within the function
pmic 41:8a63b01edd7e 143 static float a = -4.685f; // (-6.581, -2.79)
pmic 41:8a63b01edd7e 144 static float c = 3.017e+04f; // (2.853e+04, 3.181e+04)
pmic 41:8a63b01edd7e 145
pmic 41:8a63b01edd7e 146 return c/(ir_distance_cm + 1) + a;
pmic 6:e1fa1a2d7483 147 }