Project 2 - Implement the Code for controlling the retraction and extension of Airplane’s landing gear
Project-2
AIM: Write a C program Implementing the control for the retraction and extension of Airplane’s landing gear using the Finite state machine with the knowledge of various states of switch and gear.
EMBEDDED C CODE:
states.h :
#ifndef STATES_H_
#define STATES_H_
#include
/* -----Functions----- */
void Init_State_Machine();
void Gear_Down();
void Checking_Before_Takeoff();
void Raising_Gear();
void Gear_Up();
void Checking_Before_Landing();
void Lowering_Gear();
typedef enum State
{
GR_DWN,
CHK_BFR_TKFF,
RSING_GR,
GR_UP,
CHK_BFR_LND,
LWRNG_GR
}State_Type;
typedef enum Switch
{
Open,
Close//Plane is in ground
}Switch_Status;
typedef enum Pilot_Lever
{
Rising,
Falling,
UP,
DOWN
}Pilot_Lever_Status;
typedef enum Hydraulic_Mechanism
{
Working,
Malfunctioning
}Hydraulic_Mechanism_Status;
/* -----input for changing the State----- */
static volatile Switch_Status squat_switch;
static volatile Switch_Status limit_switch;
static volatile Pilot_Lever_Status pilot_lever;
static volatile Hydraulic_Mechanism_Status hydraulic_mechanism;
State_Type current_state;
typedef struct
{
char* current_state_indication;
char* light_status;
char* direction_valve_status;
char* hydraulic_pump_control_status;
char* gas_pressurized_spring_status[2];
}State_Table;
static State_Table State_Machine[6] = {
{"Gear Down","Green","Down","Enabled",{NULL,NULL}},
{"Checking Before Take Off","Green","Down","Enabled",{NULL,NULL}},
{"Raising Gear","Red","Up","Enabled",{"Disabled","Enabled"}},
{"Gear Up","Off","Null","Disabled",{NULL,NULL}},
{"Checking Before Landing","Red","Down","Enabled",{NULL,NULL}},
{"Lowering Gear","Green","Down","Enabled",{"Disabled","Enabled"}}
};
#endif /* STATES_H_ */
----------------------------------------------------------------------------------------------------------------------
main.c
static void (*state_table[])(void) = {Gear_Down, Checking_Before_Takeoff, Raising_Gear,
Gear_Up, Checking_Before_Landing, Lowering_Gear};
int main()
{
Init_State_Machine();
while(1)
{
state_table[current_state]();
}
}
----------------------------------------------------------------------------------------------------------------------
Init_machine.c
void Init_State_Machine()
{
//System Initialized and its in State_A
current_state = GR_DWN;
printf("nState Machine is initialized & Program is in Gear_Down State & Light Status : %sn"
,State_Machine[current_state].light_status);
}
-----------------------------------------------------------------------------------------------------------------------
Gear_down.c
void Gear_Down(void)
{
current_state = GR_DWN;
printf("nEnter the Pilot's Lever Position and Squat Switch Status:");
fflush(stdout);
scanf("%d %d",&pilot_lever,&squat_switch);
if(pilot_lever == Rising && squat_switch == Open)
{
current_state = CHK_BFR_TKFF;
printf("nCurrent State : %sn",State_Machine[current_state].current_state_indication);
printf("Light Status:%sn",State_Machine[current_state].light_status);
}
else
{
Gear_Down();
}
}
-----------------------------------------------------------------------------------------------------------------------
before_takeoff.c
void Checking_Before_Takeoff()
{
current_state = CHK_BFR_TKFF;
printf("nEnter the Pilot's Lever Position, Squat Switch Status nd Hydraulic Mechanism status:");
fflush(stdout);
scanf("%d %d %d",&pilot_lever,&squat_switch,&hydraulic_mechanism);
printf("nWait for 2 secn");
if(pilot_lever == Falling || squat_switch == Close)
{
Gear_Down();
}
else if(pilot_lever == UP && squat_switch == Open && hydraulic_mechanism == Working)
{
current_state = RSING_GR;
printf("nCurrent State : %s n",State_Machine[current_state].current_state_indication);
printf("Light Status: %sn",State_Machine[current_state].light_status);
printf("Direction valve Status: %snn",State_Machine[current_state].direction_valve_status);
}
else if(pilot_lever == UP && squat_switch == Open && hydraulic_mechanism == Working)
{
current_state = RSING_GR;
printf("nCurrent State : %s n",State_Machine[current_state].current_state_indication);
printf("Light Status: %sn",State_Machine[current_state].light_status);
printf("Direction valve Status: %snn",State_Machine[current_state].direction_valve_status);
printf("Gas pressurized spring system statuus: %sn",State_Machine[current_state].gas_pressurized_spring_status[hydraulic_mechanism]);
}
}
----------------------------------------------------------------------------------------------------------------------
Raising_gear.c
void Raising_Gear()
{
current_state = RSING_GR;
printf("nEnter the Limit Switch Status,Pilots Leaver Status:");
fflush(stdout);
scanf("%d %d",&limit_switch,&pilot_lever);
printf("nWait for 1 secn");
if(pilot_lever == Falling && limit_switch == Open)
{
current_state = CHK_BFR_LND;
printf("nCurrent State : %sn",State_Machine[current_state].current_state_indication);
printf("Light Status:%sn",State_Machine[current_state].light_status);
printf("Hydraulic Control for Landing Gear Status:%sn",State_Machine[current_state].hydraulic_pump_control_status);
}
else if(limit_switch == Close && pilot_lever == UP)
{
current_state = GR_UP;
printf("nCurrent State : %sn",State_Machine[current_state].current_state_indication);
printf("Light Status:%sn",State_Machine[current_state].light_status);
printf("Hydraulic Control for Landing Gear Status:%sn",State_Machine[current_state].hydraulic_pump_control_status);
}
else
{
Raising_Gear();
}
}
---------------------------------------------------------------------------------------------------------------------------------------
Gear_up.c
void Gear_Up()
{
current_state = GR_UP;
printf("nEnter the Pilot's Lever Position:");
fflush(stdout);
scanf("%d",&pilot_lever);
if(pilot_lever == Falling)
{
current_state = CHK_BFR_LND;
printf("nCurrent State : %sn",State_Machine[current_state].current_state_indication);
printf("Light Status:%sn",State_Machine[current_state].light_status);
printf("Hydraulic Control for Landing Gear Status:%sn",State_Machine[current_state].hydraulic_pump_control_status);
}
else
{
Gear_Up();
}
}
-------------------------------------------------------------------------------------------------------------------------------------
before_landing.c
void Checking_Before_Landing()
{
current_state = CHK_BFR_LND;
printf("nEnter the Pilot's Lever Position and Status of Hydraulic Mechanism:");
fflush(stdout);
scanf("%d %d",&pilot_lever,&hydraulic_mechanism);
if(pilot_lever == DOWN && hydraulic_mechanism == Working)
{
current_state = LWRNG_GR;
printf("nCurrent State : %sn",State_Machine[current_state].current_state_indication);
printf("Light Status:%sn",State_Machine[current_state].light_status);
printf("Direction Valve Status:%sn",State_Machine[current_state].direction_valve_status);
}
else if(pilot_lever == DOWN && hydraulic_mechanism == Malfunctioning)
{
current_state = LWRNG_GR;
printf("nCurrent State : %sn",State_Machine[current_state].current_state_indication);
printf("Light Status:%sn",State_Machine[current_state].light_status);
printf("Direction Valve Status:%sn",State_Machine[current_state].direction_valve_status);
printf("Gas Pressurized Spring System Status:%sn",State_Machine[current_state].gas_pressurized_spring_status[hydraulic_mechanism]);
}
if(pilot_lever == (UP || Rising || Falling))
{
Checking_Before_Landing();
}
}
------------------------------------------------------------------------------------------------------------------------------
lowering_gear.c
void Lowering_Gear()
{
current_state = LWRNG_GR;
printf("nEnter the Limit Switch Status,Pilots Leaver Status::");
fflush(stdout);
scanf("%d %d",&limit_switch,&pilot_lever);
if(pilot_lever == Rising)
{
current_state = CHK_BFR_TKFF;
printf("nCurrent State : %sn",State_Machine[current_state].current_state_indication);
printf("Light Status:%sn",State_Machine[current_state].light_status);
}
if(limit_switch == Open)
{
current_state = GR_DWN;
printf("nCurrent State : %sn",State_Machine[current_state].current_state_indication);
printf("Light Status:%sn",State_Machine[current_state].light_status);
printf("Hydraulic Control for Landing Gear Status:%sn",State_Machine[current_state].hydraulic_pump_control_status);
}
if(limit_switch == Close)
{
Lowering_Gear();
}
}
OUTPUT:
State Machine is initialized & Program is in Gear_Down State & Light Status : Green
Enter the Pilot's Lever Position and Squat Switch Status:0 0
Current State : Checking Before Take Off
Light Status:Green
Enter the Pilot's Lever Position, Squat Switch Status nd Hydraulic Mechanism status:2 0 0
Wait for 2 sec
Current State : Raising Gear
Light Status: Red
Direction valve Status: Up
Enter the Limit Switch Status,Pilots Leaver Status:1 0
Wait for 1 sec
Enter the Limit Switch Status,Pilots Leaver Status:1 2
Wait for 1 sec
Current State : Gear Up
Light Status:Off
Hydraulic Control for Landing Gear Status:Disabled
Enter the Pilot's Lever Position:1
Current State : Checking Before Landing
Light Status:Red
Hydraulic Control for Landing Gear Status:Enabled
Enter the Pilot's Lever Position and Status of Hydraulic Mechanism:3 0
Current State : Lowering Gear
Light Status:Green
Direction Valve Status:Down
Enter the Limit Switch Status,Pilots Leaver Status::0 0
Current State : Checking Before Take Off
Light Status:Green
Current State : Gear Down
Light Status:Green
Hydraulic Control for Landing Gear Status:Enabled
Enter the Pilot's Lever Position and Squat Switch Status:
