Michael Ernst Peter / Mbed OS PM2_Example_Line_Follower

Example project for the Line Follower robot.

Dependencies:   PM2_Libary Eigen

main.cpp@38:6d11788e14c0, 2022-05-05 (annotated)

Committer:
pmic
Date:
Thu May 05 18:01:37 2022 +0200
Revision:
38:6d11788e14c0
Parent:
34:702246639f02
Child:
40:eb7f8dce5787
Development ongoing

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 6:e1fa1a2d7483 5
pmic 34:702246639f02 6 # define M_PI 3.14159265358979323846 // number pi
pmic 33:cff70742569d 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 24:86f1a63e35a0 17 // while loop gets executed every main_task_period_ms milliseconds
pmic 34:702246639f02 18 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 24:86f1a63e35a0 19 Timer main_task_timer; // create Timer object which we use to run the main task every main task period time in ms
pmic 6:e1fa1a2d7483 20
pmic 24:86f1a63e35a0 21 // led on nucleo board
pmic 24:86f1a63e35a0 22 DigitalOut user_led(LED1); // create DigitalOut object to command user led
pmic 17:c19b471f05cb 23
pmic 38:6d11788e14c0 24 // Sharp GP2Y0A41SK0F, 4-40 cm IR Sensor
pmic 38:6d11788e14c0 25 float ir_distance_mV = 0.0f; // define variable to store measurement
pmic 38:6d11788e14c0 26 AnalogIn ir_analog_in(PC_2); // create AnalogIn object to read in infrared distance sensor, 0...3.3V are mapped to 0...1
pmic 38:6d11788e14c0 27
pmic 38:6d11788e14c0 28 // 78:1, 100:1, ... Metal Gearmotor 20Dx44L mm 12V CB
pmic 38:6d11788e14c0 29 DigitalOut enable_motors(PB_15); // create DigitalOut object to enable dc motors
pmic 38:6d11788e14c0 30
pmic 38:6d11788e14c0 31 float pwm_period_s = 0.00005f; // define pwm period time in seconds and create FastPWM objects to command dc motors
pmic 38:6d11788e14c0 32 FastPWM pwm_M1(PB_13); // motor M1 is closed-loop speed controlled (angle velocity)
pmic 38:6d11788e14c0 33 FastPWM pwm_M2(PA_9); // motor M2 is closed-loop speed controlled (angle velocity)
pmic 38:6d11788e14c0 34
pmic 38:6d11788e14c0 35 EncoderCounter encoder_M1(PA_6, PC_7); // create encoder objects to read in the encoder counter values
pmic 38:6d11788e14c0 36 EncoderCounter encoder_M2(PB_6, PB_7);
pmic 38:6d11788e14c0 37
pmic 38:6d11788e14c0 38 // create SpeedController and PositionController objects, default parametrization is for 78.125:1 gear box
pmic 38:6d11788e14c0 39 float max_voltage = 12.0f; // define maximum voltage of battery packs, adjust this to 6.0f V if you only use one batterypack
pmic 38:6d11788e14c0 40 float counts_per_turn = 20.0f * 78.125f; // define counts per turn at gearbox end: counts/turn * gearratio
pmic 38:6d11788e14c0 41 float kn = 180.0f / 12.0f; // define motor constant in rpm per V
pmic 38:6d11788e14c0 42 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 38:6d11788e14c0 43 float kp = 0.1f; // define custom kp, this is the default speed controller gain for gear box 78.125:1
pmic 38:6d11788e14c0 44
pmic 38:6d11788e14c0 45 SpeedController speedController_M1(counts_per_turn, kn, max_voltage, pwm_M1, encoder_M1); // default 78.125:1 gear box with default contoller parameters
pmic 38:6d11788e14c0 46 SpeedController speedController_M2(counts_per_turn, kn, max_voltage, pwm_M2, encoder_M2); // default 78.125:1 gear box with default contoller parameters
pmic 38:6d11788e14c0 47 // SpeedController speedController_M2(counts_per_turn * k_gear, kn / k_gear, max_voltage, pwm_M2, encoder_M2); // parameters adjusted to 100:1 gear
pmic 38:6d11788e14c0 48
pmic 38:6d11788e14c0 49 // sparkfun line follower array
pmic 33:cff70742569d 50 I2C i2c(PB_9, PB_8); // I2C (PinName sda, PinName scl)
pmic 33:cff70742569d 51 SensorBar sensor_bar(i2c, 0.1175f);
pmic 20:7e7325edcf5c 52
pmic 38:6d11788e14c0 53 float r_wheel = 0.0358f / 2.0f;
pmic 38:6d11788e14c0 54 float L_wheel = 0.143f;
pmic 38:6d11788e14c0 55 // transform wheel to robot
pmic 38:6d11788e14c0 56 float Crw[2][2] = {{r_wheel / 2.0f, r_wheel / 2.0f}, {r_wheel / L_wheel, -r_wheel / L_wheel}};
pmic 38:6d11788e14c0 57 // transform robot to wheel
pmic 38:6d11788e14c0 58 float Cwr[2][2] = {{1.0f / r_wheel, L_wheel / (2.0f * r_wheel)}, {1.0f / r_wheel, -L_wheel / (2.0f * r_wheel)}};
pmic 38:6d11788e14c0 59 // float Test = Crw[0][]
pmic 38:6d11788e14c0 60
pmic 1:93d997d6b232 61 int main()
pmic 23:26b3a25fc637 62 {
pmic 24:86f1a63e35a0 63 // attach button fall and rise functions to user button object
pmic 24:86f1a63e35a0 64 user_button.fall(&user_button_pressed_fcn);
pmic 24:86f1a63e35a0 65 user_button.rise(&user_button_released_fcn);
pmic 17:c19b471f05cb 66
pmic 29:d6f1ccf42a31 67 // start timer
pmic 24:86f1a63e35a0 68 main_task_timer.start();
pmic 6:e1fa1a2d7483 69
pmic 38:6d11788e14c0 70 // enable hardwaredriver dc motors: 0 -> disabled, 1 -> enabled
pmic 38:6d11788e14c0 71 enable_motors = 1;
pmic 6:e1fa1a2d7483 72
pmic 24:86f1a63e35a0 73 while (true) { // this loop will run forever
pmic 6:e1fa1a2d7483 74
pmic 24:86f1a63e35a0 75 main_task_timer.reset();
pmic 6:e1fa1a2d7483 76
pmic 24:86f1a63e35a0 77 if (do_execute_main_task) {
pmic 34:702246639f02 78
pmic 38:6d11788e14c0 79 // read analog input
pmic 38:6d11788e14c0 80 ir_distance_mV = 1.0e3f * ir_analog_in.read() * 3.3f;
pmic 38:6d11788e14c0 81
pmic 38:6d11788e14c0 82 speedController_M1.setDesiredSpeedRPS(0.5f); // set a desired speed for speed controlled dc motors M2
pmic 38:6d11788e14c0 83 speedController_M2.setDesiredSpeedRPS(0.5f); // set a desired speed for speed controlled dc motors M2
pmic 38:6d11788e14c0 84
pmic 34:702246639f02 85 /*
pmic 34:702246639f02 86 uint8_t sensor_bar_raw_value = sensor_bar.getRaw();
pmic 34:702246639f02 87 for( int i = 7; i >= 0; i-- ) {
pmic 34:702246639f02 88 printf("%d", (sensor_bar_raw_value >> i) & 0x01);
pmic 34:702246639f02 89 }
pmic 34:702246639f02 90 printf(", ");
pmic 34:702246639f02 91 */
pmic 34:702246639f02 92
pmic 34:702246639f02 93 int8_t sensor_bar_binaryPosition = sensor_bar.getBinaryPosition();
pmic 34:702246639f02 94 printf("%d, ", sensor_bar_binaryPosition);
pmic 34:702246639f02 95
pmic 34:702246639f02 96 uint8_t sensor_bar_nrOfLedsActive = sensor_bar.getNrOfLedsActive();
pmic 34:702246639f02 97 printf("%d, ", sensor_bar_nrOfLedsActive);
pmic 34:702246639f02 98
pmic 34:702246639f02 99 float sensor_bar_angleRad = 0.0f;
pmic 34:702246639f02 100 float sensor_bar_avgAngleRad = 0.0f;
pmic 34:702246639f02 101 if (sensor_bar.isAnyLedActive()) {
pmic 34:702246639f02 102 sensor_bar_angleRad = sensor_bar.getAngleRad();
pmic 34:702246639f02 103 sensor_bar_avgAngleRad = sensor_bar.getAvgAngleRad();
pmic 34:702246639f02 104 }
pmic 34:702246639f02 105 printf("%f, ", sensor_bar_angleRad * 180.0f / M_PI);
pmic 34:702246639f02 106 printf("%f\r\n", sensor_bar_avgAngleRad * 180.0f / M_PI);
pmic 34:702246639f02 107
pmic 1:93d997d6b232 108 } else {
pmic 6:e1fa1a2d7483 109
pmic 38:6d11788e14c0 110 ir_distance_mV = 0.0f;
pmic 38:6d11788e14c0 111
pmic 38:6d11788e14c0 112 speedController_M1.setDesiredSpeedRPS(0.0f);
pmic 38:6d11788e14c0 113 speedController_M2.setDesiredSpeedRPS(0.0f);
pmic 33:cff70742569d 114 }
pmic 6:e1fa1a2d7483 115
pmic 24:86f1a63e35a0 116 user_led = !user_led;
pmic 24:86f1a63e35a0 117
pmic 24:86f1a63e35a0 118 // do only output via serial what's really necessary (this makes your code slow)
pmic 33:cff70742569d 119 // printf("%d, %d\r\n", sensor_bar_raw_value_time_ms, sensor_bar_position_time_ms);
pmic 17:c19b471f05cb 120
pmic 24:86f1a63e35a0 121 // read timer and make the main thread sleep for the remaining time span (non blocking)
pmic 24:86f1a63e35a0 122 int main_task_elapsed_time_ms = std::chrono::duration_cast<std::chrono::milliseconds>(main_task_timer.elapsed_time()).count();
pmic 24:86f1a63e35a0 123 thread_sleep_for(main_task_period_ms - main_task_elapsed_time_ms);
pmic 1:93d997d6b232 124 }
pmic 1:93d997d6b232 125 }
pmic 6:e1fa1a2d7483 126
pmic 24:86f1a63e35a0 127 void user_button_pressed_fcn()
pmic 25:ea1d6e27c895 128 {
pmic 26:28693b369945 129 user_button_timer.start();
pmic 6:e1fa1a2d7483 130 user_button_timer.reset();
pmic 6:e1fa1a2d7483 131 }
pmic 6:e1fa1a2d7483 132
pmic 24:86f1a63e35a0 133 void user_button_released_fcn()
pmic 6:e1fa1a2d7483 134 {
pmic 24:86f1a63e35a0 135 // read timer and toggle do_execute_main_task if the button was pressed longer than the below specified time
pmic 24:86f1a63e35a0 136 int user_button_elapsed_time_ms = std::chrono::duration_cast<std::chrono::milliseconds>(user_button_timer.elapsed_time()).count();
pmic 6:e1fa1a2d7483 137 user_button_timer.stop();
pmic 24:86f1a63e35a0 138 if (user_button_elapsed_time_ms > 200) {
pmic 24:86f1a63e35a0 139 do_execute_main_task = !do_execute_main_task;
pmic 8:9bb806a7f585 140 }
pmic 6:e1fa1a2d7483 141 }