/****************************************************************************
Module
LineFollowing_SM.c
Revision
2.0.1
Description
This is a LineFollowing file for implementing state machines.
Notes
History
When Who What/Why
-------------- --- --------
02/27/17 09:48 jec another correction to re-assign both CurrentEvent
and ReturnEvent to the result of the During function
this eliminates the need for the prior fix and allows
the during function to-remap an event that will be
processed at a higher level.
02/20/17 10:14 jec correction to Run function to correctly assign
ReturnEvent in the situation where a lower level
machine consumed an event.
02/03/16 12:38 jec updated comments to reflect changes made in '14 & '15
converted unsigned char to bool where appropriate
spelling changes on true (was True) to match standard
removed local var used for debugger visibility in 'C32
commented out references to Start & RunLowerLevelSM so
that this can compile.
02/07/13 21:00 jec corrections to return variable (should have been
ReturnEvent, not CurrentEvent) and several EV_xxx
event names that were left over from the old version
02/08/12 09:56 jec revisions for the Events and Services Framework Gen2
02/13/10 14:29 jec revised Start and run to add new kind of entry function
to make implementing history entry cleaner
02/13/10 12:29 jec added NewEvent local variable to During function and
comments about using either it or Event as the return
02/11/10 15:54 jec more revised comments, removing last comment in during
function that belongs in the run function
02/09/10 17:21 jec updated comments about internal transitions on During
funtion
02/18/09 10:14 jec removed redundant call to RunLowerlevelSM in EV_Entry
processing in During function
02/20/07 21:37 jec converted to use enumerated type for events & states
02/13/05 19:38 jec added support for self-transitions, reworked
to eliminate repeated transition code
02/11/05 16:54 jec converted to implment hierarchy explicitly
02/25/03 10:32 jec converted to take a passed event parameter
02/18/99 10:19 jec built LineFollowing from MasterMachine.c
02/14/99 10:34 jec Began Coding
****************************************************************************/
/*----------------------------- Include Files -----------------------------*/
// Basic includes for a program using the Events and Services Framework
#include "ES_Configure.h"
#include "ES_Framework.h"
/* include header files for this state machine as well as any machines at the
next lower level in the hierarchy that are sub-machines to this machine
*/
#include "LineFollowing_SM.h"
#include "MotorService.h"
#include "ADMulti.h"
#include "inc/hw_memmap.h"
#include "inc/hw_types.h"
#include "inc/hw_nvic.h"
#include "inc/hw_timer.h"
#include "GamePlayHSM.h"
/*----------------------------- Module Defines ----------------------------*/
// define constants for the states for this machine
// and any other local defines
#define ENTRY_STATE DRIVING_FORWARD
#define INDUCTOR_THRESHOLD 3600
//For control law
#define OFFSET_SPEED_FORWARD 40.0 //duty cycle
#define LEFT_INDUCTOR_OFFSET 1170
#define LEFT_INDUCT 0
#define RIGHT_INDUCT 1
#define RIGHT_MOTOR true
#define LEFT_MOTOR false
#define MOTOR_FORWARD true
#define MOTOR_REVERSE false
#define ControlLawTime 1 //2
#define TurningWireTime 1200 //1150 was most recent but we underturned 1200
1000
#define RUNNING_AVG_ARRAY_LEN 8
#define SQUARE_UP_SPEED 80
#define STOP_TIME 5000
#define FORWARD_DUTY 100
/*---------------------------- Module Functions ---------------------------*/
/* prototypes for private functions for this machine, things like during
functions, entry & exit functions.They should be functions relevant to the
behavior of this state machine
*/
static ES_Event_t DuringDrivingForward(ES_Event_t Event);
static ES_Event_t DuringPIDControl(ES_Event_t Event);
static ES_Event_t DuringSquareUp(ES_Event_t Event);
static float Clamp(float val, float clampL, float clampH);
static uint32_t getArrayAvg(uint32_t arrayToSum[]);
/*---------------------------- Module Variables ---------------------------*/
// everybody needs a state variable, you may need others as well
static LineFollowingState_t CurrentState;
static uint32_t FieldStrengths[3]; //used to not have static
declaration
static bool firstSwitchType; //false means left, true means
right
static bool OnWire;
static const float pGain_forward = 0.020;// worked with offset speed 35
/*------------------------------ Module Code ------------------------------*/
/****************************************************************************
Function
RunLineFollowingSM
Parameters
ES_Event_t: the event to process
Returns
ES_Event_t: an event to return
Description
add your description here
Notes
uses nested switch/case to implement the machine.
Author
J. Edward Carryer, 2/11/05, 10:45AM
****************************************************************************/
ES_Event_t RunLineFollowingSM(ES_Event_t CurrentEvent)
{
bool MakeTransition = false;/* are we making a state
transition? */
LineFollowingState_t NextState = CurrentState;
ES_Event_t EntryEventKind = { ES_ENTRY, 0 }; // default to normal
entry to new state
ES_Event_t ReturnEvent = CurrentEvent; // assume we are not
consuming event
switch (CurrentState)
{
case DRIVING_FORWARD: // If current state is state one
{ // Execute During function for state one. ES_ENTRY &
ES_EXIT are
// processed here allow the lower level state machines
to re-map
// or consume the event
ReturnEvent = CurrentEvent = DuringDrivingForward(CurrentEvent);
//process any events
if (CurrentEvent.EventType != ES_NO_EVENT) //is it ES_NO_Event or
EV_LINE_HIT
{
switch (CurrentEvent.EventType)
{
case EV_LINE_HIT: //If event is event one
{ // Execute action function for state one :
event one
NextState = PID_CONTROL; //Decide what the next state will be
// for internal transitions, skip changing MakeTransition
MakeTransition = true; //mark that we are taking a transition
to next state
// if transitioning to a state with history change kind of entry
//EntryEventKind.EventType = ES_ENTRY_HISTORY;
// optionally, consume or re-map this event for the upper
// level state machine
ReturnEvent.EventType = ES_NO_EVENT;
}
break;
// repeat cases as required for relevant events
}
}
}
break;
// repeat state pattern as required for other states
case PID_CONTROL:
{
// Execute During function for state one. ES_ENTRY & ES_EXIT are
// processed here allow the lower level state machines to re-map
// or consume the event
ReturnEvent = CurrentEvent = DuringPIDControl(CurrentEvent);
//process any events
if (CurrentEvent.EventType != ES_NO_EVENT) //If an event is active
{
switch (CurrentEvent.EventType)
{
case EV_SWITCH_HIT:
{
firstSwitchType = CurrentEvent.EventParam; //sets module level
var to which switch hit (left or right)
// Execute action function for state one : event one
NextState = SQUARE_UP; //Decide what the next state will be
// for internal transitions, skip changing MakeTransition
MakeTransition = true; //mark that we are taking a transition
// if transitioning to a state with history change kind of entry
//EntryEventKind.EventType = ES_ENTRY_HISTORY;
// optionally, consume or re-map this event for the upper
// level state machine
ReturnEvent.EventType = ES_NO_EVENT;
}
break;
// repeat cases as required for relevant events
}
}
}
break;
case SQUARE_UP: // If current state is state one
{ // Execute During function for state one. ES_ENTRY & ES_EXIT
are
// processed here allow the lower level state machines to
re-map
// or consume the event
ReturnEvent = CurrentEvent = DuringSquareUp(CurrentEvent);
//process any events
if (CurrentEvent.EventType != ES_NO_EVENT) //If an event is active
{
switch (CurrentEvent.EventType)
{
case EV_SWITCH_HIT:
{
// Execute action function for state one : event one
NextState = SQUARE_UP; //Decide what the next state will be
// for internal transitions, skip changing MakeTransition
MakeTransition = false;
// if transitioning to a state with history change kind of entry
//EntryEventKind.EventType = ES_ENTRY_HISTORY;
// optionally, consume or re-map this event for the upper
// level state machine
if (CurrentEvent.EventParam != firstSwitchType)
{
ReturnEvent.EventType = EV_SWITCH_HIT; //EV_SWITCH_HIT, so
Reloading_SM moves to next state
}
else
{
//if same switch hit again, then ignore
ReturnEvent.EventType = ES_NO_EVENT;
}
}
break;
// repeat cases as required for relevant events
}
}
}
break;
}
// If we are making a state transition
if (MakeTransition == true)
{
// Execute exit function for current state
CurrentEvent.EventType = ES_EXIT;
RunLineFollowingSM(CurrentEvent);
CurrentState = NextState; //Modify state variable
// Execute entry function for new state
// this defaults to ES_ENTRY
RunLineFollowingSM(EntryEventKind);
}
return ReturnEvent;
}
/****************************************************************************
Function
StartLineFollowingSM
Parameters
None
Returns
None
Description
Does any required initialization for this state machine
Notes
Author
J. Edward Carryer, 2/18/99, 10:38AM
****************************************************************************/
void StartLineFollowingSM(ES_Event_t CurrentEvent)
{
// to implement entry to a history state or directly to a substate
// you can modify the initialization of the CurrentState variable
// otherwise just start in the entry state every time the state machine
// is started
if (ES_ENTRY_HISTORY != CurrentEvent.EventType)
{
if (OnWire)
{
CurrentState = PID_CONTROL;
}
else
{
CurrentState = ENTRY_STATE;
}
}
// call the entry function (if any) for the ENTRY_STATE
RunLineFollowingSM(CurrentEvent);
}
/****************************************************************************
Function
QueryLineFollowingSM
Parameters
None
Returns
LineFollowingState_t The current state of the LineFollowing state machine
Description
returns the current state of the LineFollowing state machine
Notes
Author
J. Edward Carryer, 2/11/05, 10:38AM
****************************************************************************/
LineFollowingState_t QueryLineFollowingSM(void)
{
return CurrentState;
}
//event checker for checking for wire
bool Check4Wire(void)
{
ADC_MultiRead(FieldStrengths);
static uint32_t InductorValsLeft[RUNNING_AVG_ARRAY_LEN] = { 0 };
static uint32_t InductorValsRight[RUNNING_AVG_ARRAY_LEN] = { 0 };
static uint32_t arrayPos = 0;
InductorValsLeft[arrayPos & 0x07] = FieldStrengths[LEFT_INDUCT] +
LEFT_INDUCTOR_OFFSET;
InductorValsRight[arrayPos & 0x07] = FieldStrengths[RIGHT_INDUCT];
arrayPos++;
uint32_t InductorLeft = getArrayAvg(InductorValsLeft);
uint32_t InductorRight = getArrayAvg(InductorValsRight);
//if we sense the wire and am not on the wire, post event & OnWire = true.
//If we sense the wire and are on the wire, do nothing. If we don't sense the
wire, OnWire = false.
if ((FieldStrengths[0] > INDUCTOR_THRESHOLD) || (FieldStrengths[1] >
INDUCTOR_THRESHOLD))
{
if (!OnWire)
{
OnWire = true;
ES_Event_t SwitchEvent;
SwitchEvent.EventType = EV_LINE_HIT;
PostMasterSM(SwitchEvent);
}
}
else
{
OnWire = false;
}
return false;
}
//function for checking if we're on the wire or not
bool IsOnWire(void)
{
return OnWire;
}
/***************************************************************************
private functions
***************************************************************************/
//Putting PID control here for line following
void ControlLaw(void)
{
static float FieldError; /* make static for
speed */
static uint32_t InductorValsLeft[RUNNING_AVG_ARRAY_LEN] = { 0 };
static uint32_t InductorValsRight[RUNNING_AVG_ARRAY_LEN] = { 0 };
static uint32_t arrayPos = 0;
//Read magnetic field strengths
ADC_MultiRead(FieldStrengths);
InductorValsLeft[arrayPos & 0x07] = FieldStrengths[LEFT_INDUCT] +
LEFT_INDUCTOR_OFFSET;
InductorValsRight[arrayPos & 0x07] = FieldStrengths[RIGHT_INDUCT];
arrayPos++;
uint32_t InductorLeft = getArrayAvg(InductorValsLeft);
uint32_t InductorRight = getArrayAvg(InductorValsRight);
//Calculate PID terms
FieldError = (float)InductorLeft - (float)InductorRight;
float RequestedDuty = pGain_forward * (FieldError); //+ dGain * (FieldError-
LastError);
RequestedDuty = Clamp(RequestedDuty, -21.0, 21.0);
RequestedDuty = (float)OFFSET_SPEED_FORWARD + RequestedDuty;
SetDuty((uint8_t)RequestedDuty, RIGHT_MOTOR); // output calculated control to
right motor
}
// constrain val to be in range clampL to clampH
static float Clamp(float val, float clampL, float clampH)
{
if (val > clampH) // if too high
{
return clampH;
}
if (val < clampL) // if too low
{
return clampL;
}
return val; // if OK as-is
}
static uint32_t getArrayAvg(uint32_t arrayToSum[])
{
uint32_t sum = 0;
for (uint8_t i = 0; i < RUNNING_AVG_ARRAY_LEN; i++)
{
sum += arrayToSum[i];
}
return sum >> 3; //sum/RUNNING_AVG_ARRAY_LEN;
}
static ES_Event_t DuringDrivingForward(ES_Event_t Event)
{
ES_Event_t ReturnEvent = Event; // assume no re-mapping or consumption
// process ES_ENTRY, ES_ENTRY_HISTORY & ES_EXIT events
if ((Event.EventType == ES_ENTRY) ||
(Event.EventType == ES_ENTRY_HISTORY))
{
// implement any entry actions required for this state machine
DriveForward(FORWARD_DUTY);
}
else if (Event.EventType == ES_EXIT)
{
//make bot turn right to align with wire
SetDuty(50, LEFT_MOTOR); //55
SetDuty(20, RIGHT_MOTOR); //12, 15, 20
//start timer to be parallel with line
ES_Timer_InitTimer(TURNING_TOWARDS_WIRE_TIMER, TurningWireTime);
}
else
// do the 'during' function for this state
{}
return ReturnEvent;
}
static ES_Event_t DuringPIDControl(ES_Event_t Event)
{
ES_Event_t ReturnEvent = Event; // assume no re-mapping or consumption
// process ES_ENTRY, ES_ENTRY_HISTORY & ES_EXIT events
if ((Event.EventType == ES_ENTRY) ||
(Event.EventType == ES_ENTRY_HISTORY))
{
// implement any entry actions required for this state machine
}
else if (Event.EventType == ES_EXIT)
{
StopMotors();
}
else
// do the 'during' function for this state
{
// printf("during for pidcontrol\n\r");
if (Event.EventType == ES_TIMEOUT)
{
if (Event.EventParam == TURNING_TOWARDS_WIRE_TIMER)
{
//Done turning towards wire, should be somewhat parallel with wire now
DriveForward(OFFSET_SPEED_FORWARD);
ControlLaw();
ES_Timer_InitTimer(CONTROL_LAW_TIMER, ControlLawTime);
}
if (Event.EventParam == CONTROL_LAW_TIMER)
{
ControlLaw();
}
ES_Timer_InitTimer(CONTROL_LAW_TIMER, ControlLawTime);
}
}
return ReturnEvent;
}
static ES_Event_t DuringSquareUp(ES_Event_t Event)
{
ES_Event_t ReturnEvent = Event; // assume no re-mapping or consumption
// process ES_ENTRY, ES_ENTRY_HISTORY & ES_EXIT events
if ((Event.EventType == ES_ENTRY) ||
(Event.EventType == ES_ENTRY_HISTORY))
{
if (firstSwitchType)
{
//right switch hit, turn towards right
SetDuty(0, RIGHT_MOTOR);
SetDuty(SQUARE_UP_SPEED, LEFT_MOTOR);
}
else
{
//left switch hit, turn towards left
SetDuty(SQUARE_UP_SPEED, RIGHT_MOTOR);
SetDuty(0, LEFT_MOTOR);
}
}
else if (Event.EventType == ES_EXIT)
{
StopMotors();
}
else
// do the 'during' function for this state
{}
return ReturnEvent;
}
