Project 2 Adaptive Cruise Control

Ans.)

Aim:-

To develop a MATLAB simulink model for Adaptive cruise control of a vehicle according to the requirements

What Is Adaptive Cruise Control?

Adaptive cruise control (ACC) is a system designed to help road vehicles maintain a safe following distance and stay within the speed limit. This system adjusts a car's speed automatically so drivers don't have to.

Adaptive Cruise Control Feature for passenger cars allows the host vehicle to adapt to the speed in line with the flow of traffic. Driving in heavy traffic or keeping a safe distance to the preceding vehicle calls for a high level of concentration. The Adaptive Cruise Control feature can reduce the stress on the driver by automatically controlling the vehicle speed & maintaining a predefined minimum distance to the preceding vehicle. As a consequence, the driver enjoys more comfort & can concentrate on the road little better.

A radar sensor is usually at the core of the Adaptive Cruise Control. Installed at the front of the vehicle, the system permanently monitors the road ahead. As long as the road ahead is clear, cruise control feature maintains the speed set by the driver. If the system spots a slower vehicle within its detection range, it gently reduces speed by releasing the accelerator or actively engaging the brake control system. If the vehicle ahead speeds up or changes lanes, the cruise control automatically accelerates to the driver's desired speed.

Objective :-

1. Developing Adaptive Cruise Control feature as per the Requirement Document using MATLAB Simulink.
2. Follow all the MBD related processes: Requirement Tagging & Traceability, SLDD creation, Configuration Parameter changes, Model Advisor check & Code Generation.
3. In Configuration Parameters: enable “Support Floating Numbers” under Code Generation settings.
4. Use Embedded Coder to generate the code.
5. If choosing code generation, Storage class for Input signals: ImportedExtern; Storage class for Output signal: Export to File; Storage class for local signals: localizable; Storage class for calibration signals: Const.
6. Choose sample time for all signals as 0.01s

Simulink Model :-

Requirement subsystems :-

Requirement 1 - Lead Vehicle :-

• Lead Vehicle is a vehicle which is driving in the road ahead of our drive vehicle. Two input signals (Signal Name: CameraInput_LeadVehicle & RadarInput_LeadVehicle).
• Ideally sensor fusion techniques will be deployed to process & analyze data from camera & radar. For complexity reasons, let’s not adapt to any such algorithms.
• We can simply add both the radar & camera inputs & the corresponding output is read as Speed profile output (Signal Name: LeadVehicle_Speed).
• Speed data of the lead vehicle is critical in implementing the Adaptive Cruise Control algorithm.

Requirement 2 - Drive Vehicle :-

• Drive Vehicle is the vehicle driven by the user & this is the vehicle which has ACC algorithm in it.
• Like the Lead Vehicle, Drive Vehicle algorithm also has 2 input signals (Signal Name: CameraInput_DriveVehicle, RadarInput_DriveVehicle) & one signal coming as an Input to this subsystem (Signal Name: Acceleration_Mode) – three inputs into this requirement in total.
• Like the above requirement, sensor fusion techniques will also be deployed here, for complexity reasons we are ignoring them.
• Two output signals come from this subsystem (Signal Name: DriveVehicle_Speed & LeadVehicle_Detected).
• Signal DriveVehicle_Speed is summation of three input signals mentioned above & LeadVehicle_Detected is renamed from Input Signal RadarInput_DriveVehicle by mere use of Signal Conversion block.

Requirement 3 - Adaptive Cruise Control Algorithm :-

• Adaptive Cruise Control feature has 3 major modes of operation: OFF Mode, STANDBY Mode & ON Mode. This particular requirement has to be implemented as state machine logic in Simulink.
• The input signals to this state machine system are (Signal Name: Time_Gap, Set_Speed, Set_Gap, CruiseSwitch, SetSwitch).
• Also, the output signals (Signal Name: DriveVehicle_Speed & LeadVehicle_Detected) from requirement-2 is fed back as an input signal into this state machine block.
• Additionally, output signal (Signal Name: LeadVehicle_Speed) from requirement-1 is given as an input signal to this state machine block as well.
• Output from this subsystem is a signal (Signal Name: Acceleration_Mode) which governs the vehicular speed of the drive vehicle which automatically adjusts its speed & velocity to match the lead vehicle.

Requirement 3a - ACC OFF MODE state logic :-

• This is the default state inside state machine logic. Output signal Acceleration_Mode is at value 0 in this state.
• This state is governed by input signal CruiseSwitch.
• If CruiseSwitch is equal to 1, state ACC STANDBY mode will get activated. If CruiseSwitch is equal to 0, state ACC OFF mode will get activated, from either ACC ON mode or ACC STANDBY mode

Requirement 3b - ACC STANDBY MODE state logic :-

• This is the second activated state inside state machine logic. Output signal Acceleration_Mode is at value 1 in this state.
• This state is governed by both input signals CruiseSwitch & SetSwitch.
• If CruiseSwitch is equal to 1, state ACC STANDBY mode will get activated. If CruiseSwitch is equal to 0, state ACC OFF mode will get activated, from either ACC ON mode or ACC STANDBY mode
• If SetSwitch is equal to 1, state ACC ON mode will get activated. If SetSwitch is equal to 0, state ACC STANDBY mode will get activated.

Requirement 3c - ACC ON MODE state logic :-

This state will be activated when input signal SetSwitch is equal to 1. There are 6 sub states to this state logic: They are:

• LeadVehicle_Detected_Follow (Default)
• LeadVehicle_Not_Detected
• LeadVehicle_Detected_Resume
• LeadVehicle_Not_Detected_Resume
• LeadVehicle_Speed_lessthan_Set_Speed

Requirement 3c (i) - LeadVehicle_Detected_Follow (ACC ON MODE) :-

• This is the default sub state inside ACC ON MODE state. Output signal Acceleration_Mode is equal to 2.
• Condition to transit from LeadVehicle_Detected_Follow to LeadVehicle_Not_Detected; Input signal condition LeadVehicle_Detected == 0.
• Condition to transit from LeadVehicle_Detected_Follow to LeadVehicle_Speed_lessthan_Set_Speed; Input Signals condition (LeadVehicle_Detected == 1) && (LeadVehicle_Speed < Set_Speed) || (Time_Gap < Set_Gap).

Requirement 3c (ii) - LeadVehicle_Not_Detected (ACC ON MODE) :-

• Output signal Acceleration_Mode is equal to 1.
• Condition to transit from LeadVehicle_Not_Detected to LeadVehicle_Detected_Follow; Input signals condition [(LeadVehicle_Detected==1) && (DriveVehicle_Speed == Set_Speed) && (LeadVehicle_Speed >= Set_Speed) && (Time_Gap >= Set_Gap)]
• Condition to transit from LeadVehicle_Not_Detected to LeadVehicle_Speed_lessthan_Set_Speed; Input signals condition [(LeadVehicle_Detected == 1) && (LeadVehicle_Speed < Set_Speed) || (Time_Gap < Set_Gap)]

Requirement 3c (iii) - LeadVehicle_Detected_Resume (ACC ON MODE) :-

• Output signal Acceleration_Mode is equal to 3.
• Condition to transit from LeadVehicle_Detected_Resume to LeadVehicle_Detected_Follow; Input signals condition [(DriveVehicle_Speed == Set_Speed) && (LeadVehicle_Speed >= Set_Speed) && (Time_Gap >= Set_Gap)]
• Condition to transit from LeadVehicle_Detected_Resume to LeadVehicle_Not_Detected_Resume; Input signal condition LeadVehicle_Detected==0.
• Condition to transit from LeadVehicle_Detected_Resume to LeadVehicle_Speed_equal_Set_Speed; Input Signal condition [(DriveVehicle_Speed < Set_Speed) && (LeadVehicle_Speed > DriveVehicle_Speed) && (Time_Gap >= Set_Gap)]

Requirement 3c (iv) - LeadVehicle_Not_Detected_Resume (ACC ON MODE) :-

• Output signal Acceleration_Mode is equal to 1.

Requirement 3c (v) - LeadVehicle_Speed_lessthan_Set_Speed (ACC ON MODE) :-

• Output signal Acceleration_Mode is equal to 4.
• Condition to transit from LeadVehicle_Speed_lessthan_Set_Speed to LeadVehicle_Not_Detected; Input signal condition [(LeadVehicle_Detected == 0) && (DriveVehicle_Speed == Set_Speed)]
• Condition to transit from LeadVehicle_Speed_lessthan_Set_Speed to LeadVehicle_Speed_equal_Set_Speed; Input signals condition [((LeadVehicle_Speed*1.25>=DriveVehicle_Speed) && (LeadVehicle_Speed * 0.75<=DriveVehicle_Speed)) && (DriveVehicle_Speed < Set_Speed) && ((Time_Gap<=1.25*Set_Gap) && (Time_Gap >=0.75*Set_Gap))]

Requirement 3c (vi) - LeadVehicle_Speed_equal_Set_Speed (ACC ON MODE) :-

• Output signal Acceleration_Mode is equal to 5.
• Condition to transit from LeadVehicle_Speed_equal_Set_Speed to LeadVehicle_Not_Detected_Resume; Input signal conditions is [(LeadVehicle_Detected == 0) || (DriveVehicle_Speed <= Set_Speed)]
• Condition to transit from LeadVehicle_Speed_equal_Set_Speed to LeadVehicle_Detected_Resume; Input signal conditions [(DriveVehicle_Speed < Set_Speed) && (LeadVehicle_Speed > DriveVehicle_Speed) || (Time_Gap >= Set_Gap)]
• Condition to transit from LeadVehicle_Speed_equal_Set_Speed to LeadVehicle_Speed_lessthan_Set_Speed; Input signals conditions [(LeadVehicle_Speed<set_speed) &&="" (leadvehicle_speed<drivevehicle_speed)="" ||="" (time_gap="=0.75*Set_Gap)]</em"></set_speed)>

The input,output and calibrated signals are defined in the Simulink liberary data directory file,all parameters are defined in the SLDD file.

For Generating the Model Advisor Report As per the MAAB guideline :-

• Click on Model Advisor

• Then click on Ok

• Then Select Modelling standard For MAB --> click on Run selected check --> click on generate code

Requirement Tagging & Traceability :-

Highlight the contain which we have to tag for subsytem.

Right Click on subsytem and selecte Requirement option and selecte Link To Selection in Word

Now we generate the c code using the embedded coder

Generate a code as shown below :-

/*

* File: Adaptive_Cruise_Control.c

*

* Code generated for Simulink model 'Adaptive_Cruise_Control'.

*

* Model version : 1.6

* Simulink Coder version : 9.5 (R2021a) 14-Nov-2020

* C/C++ source code generated on : Wed Feb 16 00:29:09 2022

*

* Target selection: ert.tlc

* Embedded hardware selection: Intel->x86-64 (Windows64)

* Code generation objectives:

* 1. Execution efficiency

* 2. RAM efficiency

* Validation result: Not run

*/

#include "Adaptive_Cruise_Control.h"

/* Named constants for Chart: '<S3>/ACC_Logic' */

#define IN_ACC_OFF_MODE ((uint8_T)1U)

#define IN_ACC_ON_MODE ((uint8_T)2U)

#define IN_ACC_STANDBY_MODE ((uint8_T)3U)

#define IN_LeadVehicle_Detected_Follow ((uint8_T)1U)

#define IN_LeadVehicle_Detected_Resume ((uint8_T)2U)

#define IN_LeadVehicle_Not_Detected ((uint8_T)3U)

#define IN_LeadVehicle_Not_Detected_Res ((uint8_T)4U)

#define IN_LeadVehicle_Speed_equal_Set_ ((uint8_T)5U)

#define IN_LeadVehicle_Speed_lessthan_S ((uint8_T)6U)

#define IN_NO_ACTIVE_CHILD ((uint8_T)0U)

/* Block signals and states (default storage) */

DW rtDW;

/* External inputs (root inport signals with default storage) */

ExtU rtU;

/* External outputs (root outports fed by signals with default storage) */

ExtY rtY;

/* Real-time model */

static RT_MODEL rtM_;

RT_MODEL *const rtM = &rtM_;

/* Model step function */

void Adaptive_Cruise_Control_step(void)

{

real_T rtb_Add;

real_T rtb_Add_g;

int32_T rtb_Acceleration_mode;

/* Sum: '<S4>/Add' incorporates:

* Inport: '<Root>/CameraInput_LeadVehicle'

* Inport: '<Root>/RadarInput_LeadVehicle'

*/

rtb_Add = rtU.CameraInput_LeadVehicle + rtU.RadarInput_LeadVehicle;

/* Sum: '<S2>/Add' incorporates:

* Inport: '<Root>/CameraInput_DriveVehicle'

* Inport: '<Root>/RadarInput_DriveVehicle'

* UnitDelay: '<S1>/Unit Delay'

*/

rtb_Add_g = (rtU.CameraInput_DriveVehicle + rtU.RadarInput_DriveVehicle) +

rtDW.UnitDelay_DSTATE;

/* Chart: '<S3>/ACC_Logic' incorporates:

* Inport: '<Root>/CruiseSwitch'

* Inport: '<Root>/RadarInput_DriveVehicle'

* Inport: '<Root>/SetSwitch'

* Inport: '<Root>/Set_Gap'

* Inport: '<Root>/Set_Speed'

* Inport: '<Root>/Time_Gap'

*/

if (rtDW.is_active_c3_Adaptive_Cruise_Co == 0U) {

rtDW.is_active_c3_Adaptive_Cruise_Co = 1U;

rtDW.is_c3_Adaptive_Cruise_Control = IN_ACC_OFF_MODE;

rtb_Acceleration_mode = 0;

} else {

switch (rtDW.is_c3_Adaptive_Cruise_Control) {

case IN_ACC_OFF_MODE:

rtb_Acceleration_mode = 0;

if (rtU.CruiseSwitch == 1.0) {

rtDW.is_c3_Adaptive_Cruise_Control = IN_ACC_STANDBY_MODE;

rtb_Acceleration_mode = 1;

}

break;

case IN_ACC_ON_MODE:

if (rtU.SetSwitch == 0.0) {

rtDW.is_ACC_ON_MODE = IN_NO_ACTIVE_CHILD;

rtDW.is_c3_Adaptive_Cruise_Control = IN_ACC_STANDBY_MODE;

rtb_Acceleration_mode = 1;

} else if (rtU.CruiseSwitch == 0.0) {

rtDW.is_ACC_ON_MODE = IN_NO_ACTIVE_CHILD;

rtDW.is_c3_Adaptive_Cruise_Control = IN_ACC_OFF_MODE;

rtb_Acceleration_mode = 0;

} else {

switch (rtDW.is_ACC_ON_MODE) {

case IN_LeadVehicle_Detected_Follow:

rtb_Acceleration_mode = 2;

if (rtU.RadarInput_DriveVehicle == 0.0) {

rtDW.is_ACC_ON_MODE = IN_LeadVehicle_Not_Detected;

rtb_Acceleration_mode = 1;

}

break;

case IN_LeadVehicle_Detected_Resume:

rtb_Acceleration_mode = 3;

if ((rtb_Add_g == rtU.Set_Speed) && (rtb_Add >= rtU.Set_Speed) &&

(rtU.Time_Gap >= rtU.Set_Gap)) {

rtDW.is_ACC_ON_MODE = IN_LeadVehicle_Detected_Follow;

rtb_Acceleration_mode = 2;

} else if (rtU.RadarInput_DriveVehicle == 0.0) {

rtDW.is_ACC_ON_MODE = IN_LeadVehicle_Not_Detected_Res;

rtb_Acceleration_mode = 1;

} else if ((rtb_Add_g < rtU.Set_Speed) && (rtb_Add > rtb_Add_g) &&

(rtU.Time_Gap >= rtU.Set_Gap)) {

rtDW.is_ACC_ON_MODE = IN_LeadVehicle_Speed_equal_Set_;

rtb_Acceleration_mode = 5;

}

break;

case IN_LeadVehicle_Not_Detected:

rtb_Acceleration_mode = 1;

if ((rtU.RadarInput_DriveVehicle == 1.0) && (rtb_Add_g ==

rtU.Set_Speed) && (rtb_Add >= rtU.Set_Speed) && (rtU.Time_Gap >=

rtU.Set_Gap)) {

rtDW.is_ACC_ON_MODE = IN_LeadVehicle_Detected_Follow;

rtb_Acceleration_mode = 2;

} else if (((rtU.RadarInput_DriveVehicle == 1.0) && (rtb_Add <

rtU.Set_Speed)) || (rtU.Time_Gap < rtU.Set_Gap)) {

rtDW.is_ACC_ON_MODE = IN_LeadVehicle_Speed_lessthan_S;

rtb_Acceleration_mode = 4;

}

break;

case IN_LeadVehicle_Not_Detected_Res:

rtb_Acceleration_mode = 1;

break;

case IN_LeadVehicle_Speed_equal_Set_:

rtb_Acceleration_mode = 5;

if ((rtU.RadarInput_DriveVehicle == 0.0) || (rtb_Add_g <=

rtU.Set_Speed)) {

rtDW.is_ACC_ON_MODE = IN_LeadVehicle_Not_Detected_Res;

rtb_Acceleration_mode = 1;

} else if (((rtb_Add_g < rtU.Set_Speed) && (rtb_Add > rtb_Add_g)) ||

(rtU.Time_Gap >= rtU.Set_Gap)) {

rtDW.is_ACC_ON_MODE = IN_LeadVehicle_Detected_Resume;

rtb_Acceleration_mode = 3;

} else if (((rtb_Add < rtU.Set_Speed) && (rtb_Add < rtb_Add_g)) ||

(0.75 * rtU.Set_Gap == rtU.Time_Gap)) {

rtDW.is_ACC_ON_MODE = IN_LeadVehicle_Speed_lessthan_S;

rtb_Acceleration_mode = 4;

}

break;

default:

/* case IN_LeadVehicle_Speed_lessthan_Set_Speed: */

rtb_Acceleration_mode = 4;

if ((rtU.RadarInput_DriveVehicle == 0.0) && (rtb_Add_g ==

rtU.Set_Speed)) {

rtDW.is_ACC_ON_MODE = IN_LeadVehicle_Not_Detected;

rtb_Acceleration_mode = 1;

} else if ((rtb_Add * 1.25 >= rtb_Add_g) && (rtb_Add * 0.75 <=

rtb_Add_g) && (rtb_Add_g < rtU.Set_Speed) && (rtU.Time_Gap

<= 1.25 * rtU.Set_Gap) && (rtU.Time_Gap >= 0.75 *

rtU.Set_Gap)) {

rtDW.is_ACC_ON_MODE = IN_LeadVehicle_Speed_equal_Set_;

rtb_Acceleration_mode = 5;

}

break;

}

}

break;

default:

/* case IN_ACC_STANDBY_MODE: */

rtb_Acceleration_mode = 1;

if (rtU.CruiseSwitch == 0.0) {

rtDW.is_c3_Adaptive_Cruise_Control = IN_ACC_OFF_MODE;

rtb_Acceleration_mode = 0;

} else if (rtU.SetSwitch == 1.0) {

rtDW.is_c3_Adaptive_Cruise_Control = IN_ACC_ON_MODE;

rtDW.is_ACC_ON_MODE = IN_LeadVehicle_Detected_Follow;

rtb_Acceleration_mode = 2;

}

break;

}

}

/* End of Chart: '<S3>/ACC_Logic' */

/* Outport: '<Root>/Acceleration_mode' */

rtY.Acceleration_mode = rtb_Acceleration_mode;

/* Update for UnitDelay: '<S1>/Unit Delay' incorporates:

* Outport: '<Root>/Acceleration_mode'

*/

rtDW.UnitDelay_DSTATE = rtb_Acceleration_mode;

}

/* Model initialize function */

void Adaptive_Cruise_Control_initialize(void)

{

/* (no initialization code required) */

}

/*

* File trailer for generated code.

*

* [EOF]

*/

Result :-

The Simulink model for adaptive cruise control of a vehicle was designed according to the requirements complying with the standards and the embedded code for the feature was generated respectively.