StateMachine.cpp

00001 /*
00002  * StateMachine.cpp
00003  * Copyright (c) 2020, ZHAW
00004  * All rights reserved.
00005  */
00006 
00007 #include <cmath>
00008 #include "StateMachine.h"
00009 
00010 using namespace std;
00011 
00012 const float StateMachine::PERIOD = 0.01f;                   // period of task in [s]
00013 const float StateMachine::DISTANCE_THRESHOLD = 0.25f;        // minimum allowed distance to obstacle in [m]
00014 const float StateMachine::TRANSLATIONAL_VELOCITY = 1.0f;    // translational velocity in [m/s]
00015 const float StateMachine::ROTATIONAL_VELOCITY = 1.5f;       // rotational velocity in [rad/s]
00016 
00017 /**
00018  * Creates and initializes a state machine object.
00019  */
00020 StateMachine::StateMachine(Controller& controller, DigitalOut& enableMotorDriver, DigitalOut& led0, DigitalOut& led1, DigitalOut& led2, DigitalOut& led3, DigitalOut& led4, DigitalOut& led5, DigitalIn& button, IRSensor& irSensor0, IRSensor& irSensor1, IRSensor& irSensor2, IRSensor& irSensor3, IRSensor& irSensor4, IRSensor& irSensor5) : controller(controller), enableMotorDriver(enableMotorDriver), led0(led0), led1(led1), led2(led2), led3(led3), led4(led4), led5(led5), button(button), irSensor0(irSensor0), irSensor1(irSensor1), irSensor2(irSensor2), irSensor3(irSensor3), irSensor4(irSensor4), irSensor5(irSensor5) {
00021     
00022     enableMotorDriver = 0;
00023     state = ROBOT_OFF;
00024     buttonNow = button;
00025     buttonBefore = buttonNow;
00026     
00027     ticker.attach(callback(this, &StateMachine::run), PERIOD);
00028 }
00029 
00030 /**
00031  * Deletes the state machine object and releases all allocated resources.
00032  */
00033 StateMachine::~StateMachine() {
00034     
00035     ticker.detach();
00036 }
00037 
00038 /**
00039  * Gets the actual state of this state machine.
00040  * @return the actual state as an int constant.
00041  */
00042 int StateMachine::getState() {
00043     
00044     return state;
00045 }
00046 
00047 /**
00048  * This method is called periodically by the ticker object and implements the
00049  * logic of the state machine.
00050  */
00051 void StateMachine::run() {
00052     
00053     // set the leds based on distance measurements
00054     
00055     led0 = irSensor0 < DISTANCE_THRESHOLD;
00056     led1 = irSensor1 < DISTANCE_THRESHOLD;
00057     led2 = irSensor2 < DISTANCE_THRESHOLD;
00058     led3 = irSensor3 < DISTANCE_THRESHOLD;
00059     led4 = irSensor4 < DISTANCE_THRESHOLD;
00060     led5 = irSensor5 < DISTANCE_THRESHOLD;
00061     
00062     // implementation of the state machine
00063     
00064     switch (state) {
00065         
00066         case ROBOT_OFF:
00067             
00068             buttonNow = button;
00069             
00070             if (buttonNow && !buttonBefore) {   // detect button rising edge
00071                 
00072                 enableMotorDriver = 1;
00073                 
00074                 controller.setTranslationalVelocity(TRANSLATIONAL_VELOCITY);
00075                 controller.setRotationalVelocity(0.0f);
00076                 
00077                 state = MOVE_FORWARD;
00078             }
00079             
00080             buttonBefore = buttonNow;
00081             
00082             break;
00083             
00084         case MOVE_FORWARD:
00085             
00086             if (!led2 && !led3 && !led4) {
00087                 controller.setTranslationalVelocity(TRANSLATIONAL_VELOCITY);
00088                 controller.setRotationalVelocity(0.0f);
00089                 }
00090             else if(led2 || (led2&&led3)){
00091                 state = TURN_LEFT;
00092                 }
00093             else if(led4 || (led3&&led4)){
00094                 state = TURN_RIGHT;
00095                 }
00096             else if(led2 && led3 && led4){
00097                state = SLOWING_DOWN;
00098                }
00099                 
00100                 
00101             // bitte implementieren!
00102             
00103             break;
00104             
00105         case TURN_LEFT:
00106        
00107             
00108            
00109             if(led4 || led3 || (led4&&led3)){
00110                 controller.setTranslationalVelocity(0.0f);
00111                 controller.setRotationalVelocity(-ROTATIONAL_VELOCITY);
00112                 }
00113          
00114             state = MOVE_FORWARD;
00115             // bitte implementieren!
00116             
00117             break;
00118             
00119         case TURN_RIGHT:
00120         
00121             if(led3 || led2 || (led2&&led3)){
00122                 controller.setTranslationalVelocity(0.0f);
00123                 controller.setRotationalVelocity(ROTATIONAL_VELOCITY);
00124                 }
00125             
00126             state = MOVE_FORWARD;
00127             // bitte implementieren!
00128             
00129             break;
00130             
00131         case SLOWING_DOWN:
00132             if (controller.getActualTranslationalVelocity()>0.0f){
00133                     controller.setTranslationalVelocity(0.0f);
00134             } else if (controller.getActualTranslationalVelocity()<= 0.0001f){
00135                 enableMotorDriver = 0;
00136                 }
00137             state = ROBOT_OFF;
00138             
00139             // bitte implementieren!
00140             
00141             break;
00142             
00143         default:
00144             
00145             state = ROBOT_OFF;
00146     }
00147 }
00148