main.cpp

00001 #include <mbed.h>
00002 
00003 #include "PM2_Libary.h"
00004 #include "Eigen/Dense.h"
00005 
00006 # define M_PI 3.14159265358979323846  // number pi
00007 
00008 // logical variable main task
00009 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
00010 
00011 // user button on nucleo board
00012 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)
00013 InterruptIn user_button(PC_13);     // create InterruptIn interface object to evaluate user button falling and rising edge (no blocking code in ISR)
00014 void user_button_pressed_fcn();     // custom functions which gets executed when user button gets pressed and released, definition below
00015 void user_button_released_fcn();
00016 
00017 float ir_distance_mV2cm(float ir_distance_mV);
00018 
00019 int main()
00020 {
00021     // while loop gets executed every main_task_period_ms milliseconds
00022     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
00023     Timer main_task_timer;                // create Timer object which we use to run the main task every main task period time in ms
00024 
00025     // a coutner
00026     uint32_t main_task_cntr = 0;
00027 
00028     // led on nucleo board
00029     DigitalOut user_led(LED1);      // create DigitalOut object to command user led
00030 
00031     // Sharp GP2Y0A41SK0F, 4-40 cm IR Sensor
00032     float ir_distance_mV = 0.0f;    // define variable to store measurement
00033     float ir_distance_cm = 0.0f;    // compensated sensor value in cm
00034     AnalogIn ir_analog_in(PC_2);    // create AnalogIn object to read in infrared distance sensor, 0...3.3V are mapped to 0...1
00035 
00036     // create SensorBar object for sparkfun line follower array, only use this if it is connected (blocking your code if not)
00037     float sensor_bar_avgAngleRad = 0.0f;
00038     I2C i2c(PB_9, PB_8);
00039     //SensorBar sensor_bar(i2c, 0.1175f); // second input argument is distance from bar to wheel axis
00040 
00041     // 78:1, 100:1, ... Metal Gearmotor 20Dx44L mm 12V CB
00042     DigitalOut enable_motors(PB_15);    // create DigitalOut object to enable dc motors
00043 
00044     FastPWM pwm_M1(PB_13);               // motor M1 is closed-loop speed controlled (angle velocity)
00045     FastPWM pwm_M2(PA_9);                // motor M2 is closed-loop position controlled (angle controlled)
00046 
00047     EncoderCounter  encoder_M1(PA_6, PC_7); // create encoder objects to read in the encoder counter values
00048     EncoderCounter  encoder_M2(PB_6, PB_7);
00049 
00050     // create SpeedController and PositionController objects, default parametrization is for 78.125:1 gear box
00051     const float max_voltage = 12.0f;                  // define maximum voltage of battery packs, adjust this to 6.0f V if you only use one batterypack
00052     const float counts_per_turn = 20.0f * 78.125f;    // define counts per turn at gearbox end: counts/turn * gearratio
00053     const float kn = 180.0f / 12.0f;                  // define motor constant in rpm per V
00054     //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
00055     //const float kp = 0.1f;                            // define custom kp, this is the default speed controller gain for gear box 78.125:1
00056 
00057     SpeedController speedController_M1(counts_per_turn, kn, max_voltage, pwm_M1, encoder_M1); // default 78.125:1 gear box  with default contoller parameters
00058     //SpeedController speedController_M1(counts_per_turn * k_gear, kn / k_gear, max_voltage, pwm_M1, encoder_M1); // parameters adjusted to 100:1 gear
00059     speedController_M1.setMaxAccelerationRPS(999.0f);  // disable internal trajectory planer
00060 
00061     PositionController positionController_M2(counts_per_turn, kn, max_voltage, pwm_M2, encoder_M2); // default 78.125:1 gear with default contoller parameters
00062     //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
00063     //positionController_M2.setSpeedCntrlGain(kp * k_gear);
00064     positionController_M2.setMaxAccelerationRPS(999.0f);  // disable internal trajectory planer
00065     // define maximum speed that the position controller is changig the speed, has to be smaller or equal to kn * max_voltage
00066     float max_speed_rps = 2.0f;
00067     positionController_M2.setMaxVelocityRPS(max_speed_rps);
00068 
00069     // attach button fall and rise functions to user button object
00070     user_button.fall(&user_button_pressed_fcn);
00071     user_button.rise(&user_button_released_fcn);
00072 
00073     // start timer
00074     main_task_timer.start();
00075 
00076     // enable hardwaredriver dc motors: 0 -> disabled, 1 -> enabled
00077     enable_motors = 1;
00078 
00079     while (true) { // this loop will run forever
00080 
00081         main_task_timer.reset();
00082         
00083         // read analog input
00084         ir_distance_mV = 1.0e3f * ir_analog_in.read() * 3.3f;
00085         ir_distance_cm = ir_distance_mV2cm(ir_distance_mV);
00086         
00087         // read SensorBar, only use this if it is connected (blocking your code if not)
00088         //if (sensor_bar.isAnyLedActive()) {
00089         //    sensor_bar_avgAngleRad = sensor_bar.getAvgAngleRad();
00090         //}
00091 
00092         if (do_execute_main_task) {
00093 
00094             speedController_M1.setDesiredSpeedRPS(2.0f);
00095             positionController_M2.setDesiredRotation(3.0f);
00096 
00097         } else {
00098 
00099             speedController_M1.setDesiredSpeedRPS(0.0f);
00100             positionController_M2.setDesiredRotation(0.0f);
00101             
00102         }
00103 
00104         // user_led is switching its state every second
00105         if ( (main_task_cntr%(1000 / main_task_period_ms) == 0) && (main_task_cntr!=0) ) {
00106             user_led = !user_led;
00107         }
00108         main_task_cntr++;
00109         
00110         // do only output via serial what's really necessary (this makes your code slow)
00111         /*
00112         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",
00113                ir_distance_mV,
00114                ir_distance_cm,
00115                sensor_bar_avgAngleRad,
00116                speedController_M1.getSpeedRPS(),
00117                positionController_M2.getRotation());
00118         */
00119 
00120         // read timer and make the main thread sleep for the remaining time span (non blocking)
00121         int main_task_elapsed_time_ms = std::chrono::duration_cast<std::chrono::milliseconds>(main_task_timer.elapsed_time()).count();
00122         thread_sleep_for(main_task_period_ms - main_task_elapsed_time_ms);
00123     }
00124 }
00125 
00126 void user_button_pressed_fcn()
00127 {
00128     user_button_timer.start();
00129     user_button_timer.reset();
00130 }
00131 
00132 void user_button_released_fcn()
00133 {
00134     // read timer and toggle do_execute_main_task if the button was pressed longer than the below specified time
00135     int user_button_elapsed_time_ms = std::chrono::duration_cast<std::chrono::milliseconds>(user_button_timer.elapsed_time()).count();
00136     user_button_timer.stop();
00137     if (user_button_elapsed_time_ms > 200) {
00138         do_execute_main_task = !do_execute_main_task;
00139     }
00140 }
00141 
00142 float ir_distance_mV2cm(float ir_distance_mV)
00143 {
00144     // defining these variables static makes them persistent within the function
00145     static float a =    -4.685f; //  (-6.581, -2.79)
00146     static float c = 3.017e+04f; //  (2.853e+04, 3.181e+04)
00147 
00148     return c/(ir_distance_mV + 1) + a;
00149 }