Project 2 Adaptive Cruise Control

Main Project – Adaptive Cruise Control (ACC)

General Overview:

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 from 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 a 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, the 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.

Standard Adaptive Cruise Control can be activated from speeds of around 30 km/h (20 mph) upwards and supports the driver, primarily on cross-country journeys or on freeways. The cruise control stops & go variant is also active at speeds below 30 km/h (20 mph). It can maintain the set distance to the preceding vehicle even at very low speeds and can decelerate to a complete standstill. When the vehicle stops longer, the driver needs only to reactivate the system by briefly stepping on the gas pedal to return to cruise control mode. In this way, cruise control stops & go supports the driver even in heavy traffic and traffic jams.

Since Adaptive Cruise Control is a comfort and convenience system, brake interventions and vehicle acceleration only take place within defined limits. Even with Adaptive Cruise Control switched on, it remains the driver’s responsibility to monitor the speed and distance from the vehicle in front.

The objective of the Main Project:

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

Requirement 1– Lead Vehicle:

• Lead Vehicle is a vehicle that is driving on 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 cameras & 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 that has an ACC algorithm in it.
• Like the Lead Vehicle, the 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 the 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 are fed back as an input signal into this state machine block.
• Additionally, the 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 and 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 the 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 the input signal SetSwitch equals 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
• LeadVehicle_Speed_equal_Set_Speed

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

• This is the default sub-state inside the 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)]
  

Signals & Calibration Data List:

Explanation:

Simulink Model: Adaptive Cruise Control (ACC):

As per the requirements, I created a Simulink model for the adaptive cruise control feature.

Here consist of 3 Requirement subsystems,

• Requirement 1: Lead vehicle subsystem.
• Requirement 2: Drive vehicle subsystem.
• Requirement 3: Adaptive Cruise Control subsystem.

Requirement Tagging:

Requirement 1:

As to find out the lead vehicle speed is quite complicated, for simplicity as per requirement 1, the input from the CameraInput_LeadVehicle signal and RadarInput_LeadVehicle signal are summed up to get the LeadVehicle_Speed output.

Requirement 2:

For DriveVehicle_Speed calculation we are adding CameraInput_DriveVehicle, RadarInput_DriveVehicle, and Acceleration_Mode feedback from the Cruise control algorithm.

The outputs from this subsystem as DriveVehicle_Speed and Lead_Vehicle_Detected by propagating RadarInput_DriveVehicle in to signal conversion block.

Requirement 3:

In this subsystem we are using a state flow logics to implement the requirements 3a,3b,3c,3c(i),3c(ii),3c(iii),3c(iv),3c(v),3c(vi).

The inputs for the state flow are,

• Time_Gap.
• Set_Speed.
• Set_Gap.
• CruiseSwitch.
• SetSwitch.
• DriveVehicle_Speed from Requirement 2 subsystem.
• LeadVehicle_Speed from Requirement 1 subsystem.
• LeadVehicle_Detected from Requirement 2 subsystem.

The output from this subsystem is,

• Acceleration_Mode-Based on the LeadVehicle_Speed the Acceleration_Mode adjust its controlling acceleration given output to maintain a constant speed.

State flow logic(Adaptive Cruise Control Logic):

In this logic, we had created three modes of operation,

1. ACC_OFF mode.
2. ACC_STANDBY mode.
3. ACC_ON mode.

In ACC_ON mode we have further 6 modes of operations as,

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

All these modes of operations are modeled as per the given as mentioned in the requirements section.

Modeling and Model Settings:

SLDD file creation:

All the input and output signals resolved and propagated in this model are declared in the SLDD file created as shown below,

The signal parameters are declared as per the SLDD data requirements mentioned earlier.

The code generated from output signals are stored in ADAS_CruiseControl.h and ADAS_CruiseControl.c files.

Model advisor check:

For the model advisor check of MAB guidelines we are getting the report as shown below,

The report for the model advisor check is attached to this project submission.

Code Generation:

/*
 * File: Project2.c
 *
 * Code generated for Simulink model 'Project2'.
 *
 * Model version                  : 1.34
 * Simulink Coder version         : 9.5 (R2021a) 14-Nov-2020
 * C/C++ source code generated on : Sat Jul 16 12:09:40 2022
 *
 * Target selection: ert.tlc
 * Embedded hardware selection: Intel->x86-64 (Windows64)
 * Code generation objectives: specified
 * Validation result: Run
 */

#include "Project2.h"
#include "Project2_private.h"

/* Named constants for Chart: '/ACC_logic' */
#define IN_LeadVehicle_Detected_Follow ((uint8_T)1U)
#define IN_LeadVehicle_Detected_Resume ((uint8_T)2U)
#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 Pro_IN_LeadVehicle_Not_Detected ((uint8_T)3U)
#define Project2_IN_ACC_OFF_MODE       ((uint8_T)1U)
#define Project2_IN_ACC_ON_MODE        ((uint8_T)2U)
#define Project2_IN_ACC_STANDBY_MODE   ((uint8_T)3U)
#define Project2_IN_NO_ACTIVE_CHILD    ((uint8_T)0U)

/* Exported data definition */

/* Definition for custom storage class: ExportToFile */
uint8_T Acceleration_Mode;             /* '/Unit Delay' */

/* Block states (default storage) */
DW_Project2_T Project2_DW;

/* External outputs (root outports fed by signals with default storage) */
ExtY_Project2_T Project2_Y;

/* Real-time model */
static RT_MODEL_Project2_T Project2_M_;
RT_MODEL_Project2_T *const Project2_M = &Project2_M_;
real_T rt_roundd_snf(real_T u)
{
  real_T y;
  if (fabs(u) < 4.503599627370496E+15) {
    if (u >= 0.5) {
      y = floor(u + 0.5);
    } else if (u > -0.5) {
      y = u * 0.0;
    } else {
      y = ceil(u - 0.5);
    }
  } else {
    y = u;
  }

  return y;
}

/* Model step function */
void Project2_step(void)
{
  /* local block i/o variables */
  uint8_T LeadVehicle_Speed;
  uint8_T DriveVehicle_Speed;
  uint8_T LeadVehicle_Detected;
  int32_T tmp;
  int32_T tmp_0;
  uint8_T tmp_1;
  uint8_T tmp_2;

  /* Sum: '/Add' incorporates:
   *  Inport: '/CameraInput_LeadVehicle'
   *  Inport: '/RadarInput_LeadVehicle'
   */
  LeadVehicle_Speed = (uint8_T)((uint32_T)CameraInput_LeadVehicle +
    RadarInput_LeadVehicle);

  /* UnitDelay: '/Unit Delay' */
  Acceleration_Mode = Project2_Y.Acceleration_Mode_h;

  /* Sum: '/Add' incorporates:
   *  Inport: '/CameraInput_DriveVehicle'
   *  Inport: '/RadarInput_DriveVehicle'
   */
  DriveVehicle_Speed = (uint8_T)((uint32_T)(uint8_T)((uint32_T)
    CameraInput_DriveVehicle + Acceleration_Mode) + RadarInput_DriveVehicle);

  /* SignalConversion: '/Signal Conversion' incorporates:
   *  Inport: '/RadarInput_DriveVehicle'
   */
  LeadVehicle_Detected = RadarInput_DriveVehicle;

  /* Chart: '/ACC_logic' incorporates:
   *  Inport: '/CruiseSwith'
   *  Inport: '/SetSwitch'
   *  Inport: '/Set_Gap'
   *  Inport: '/Set_Speed'
   *  Inport: '/Time_Gap'
   *  UnitDelay: '/Unit Delay'
   */
  if (Project2_DW.is_active_c3_Project2 == 0U) {
    Project2_DW.is_active_c3_Project2 = 1U;
    Project2_DW.is_c3_Project2 = Project2_IN_ACC_OFF_MODE;
    Project2_Y.Acceleration_Mode_h = 0U;
  } else {
    switch (Project2_DW.is_c3_Project2) {
     case Project2_IN_ACC_OFF_MODE:
      Project2_Y.Acceleration_Mode_h = 0U;
      if (CruiseSwitch) {
        Project2_DW.is_c3_Project2 = Project2_IN_ACC_STANDBY_MODE;
        Project2_Y.Acceleration_Mode_h = 1U;
      }
      break;

     case Project2_IN_ACC_ON_MODE:
      if (!SetSwitch) {
        Project2_DW.is_ACC_ON_MODE = Project2_IN_NO_ACTIVE_CHILD;
        Project2_DW.is_c3_Project2 = Project2_IN_ACC_STANDBY_MODE;
        Project2_Y.Acceleration_Mode_h = 1U;
      } else if (!CruiseSwitch) {
        Project2_DW.is_ACC_ON_MODE = Project2_IN_NO_ACTIVE_CHILD;
        Project2_DW.is_c3_Project2 = Project2_IN_ACC_OFF_MODE;
        Project2_Y.Acceleration_Mode_h = 0U;
      } else {
        switch (Project2_DW.is_ACC_ON_MODE) {
         case IN_LeadVehicle_Detected_Follow:
          Project2_Y.Acceleration_Mode_h = 2U;
          if (LeadVehicle_Detected == 0) {
            Project2_DW.is_ACC_ON_MODE = Pro_IN_LeadVehicle_Not_Detected;
            Project2_Y.Acceleration_Mode_h = 1U;
          } else if (((LeadVehicle_Detected == 1) && (LeadVehicle_Speed <
                       Set_Speed)) || (Time_Gap < Set_Gap)) {
            Project2_DW.is_ACC_ON_MODE = IN_LeadVehicle_Speed_lessthan_s;
            Project2_Y.Acceleration_Mode_h = 4U;
          }
          break;

         case IN_LeadVehicle_Detected_Resume:
          Project2_Y.Acceleration_Mode_h = 3U;
          if ((DriveVehicle_Speed == Set_Speed) && (LeadVehicle_Speed >=
               Set_Speed) && (Time_Gap >= Set_Gap)) {
            Project2_DW.is_ACC_ON_MODE = IN_LeadVehicle_Detected_Follow;
            Project2_Y.Acceleration_Mode_h = 2U;
          } else if (LeadVehicle_Detected == 0) {
            Project2_DW.is_ACC_ON_MODE = IN_LeadVehicle_Not_Detected_Res;
            Project2_Y.Acceleration_Mode_h = 1U;
          } else if ((DriveVehicle_Speed < Set_Speed) && (LeadVehicle_Speed >
                      DriveVehicle_Speed) && (Time_Gap >= Set_Gap)) {
            Project2_DW.is_ACC_ON_MODE = IN_LeadVehicle_Speed_equal_set_;
            Project2_Y.Acceleration_Mode_h = 5U;
          }
          break;

         case Pro_IN_LeadVehicle_Not_Detected:
          Project2_Y.Acceleration_Mode_h = 1U;
          if ((LeadVehicle_Detected == 1) && (DriveVehicle_Speed == Set_Speed) &&
              (LeadVehicle_Speed >= Set_Speed) && (Time_Gap >= Set_Gap)) {
            Project2_DW.is_ACC_ON_MODE = IN_LeadVehicle_Detected_Follow;
            Project2_Y.Acceleration_Mode_h = 2U;
          } else if (((LeadVehicle_Detected == 1) && (LeadVehicle_Speed <
                       Set_Speed)) || (Time_Gap < Set_Gap)) {
            Project2_DW.is_ACC_ON_MODE = IN_LeadVehicle_Speed_lessthan_s;
            Project2_Y.Acceleration_Mode_h = 4U;
          }
          break;

         case IN_LeadVehicle_Not_Detected_Res:
          Project2_Y.Acceleration_Mode_h = 1U;
          break;

         case IN_LeadVehicle_Speed_equal_set_:
          Project2_Y.Acceleration_Mode_h = 5U;
          if (((DriveVehicle_Speed < Set_Speed) && (LeadVehicle_Speed >
                DriveVehicle_Speed)) || (Time_Gap >= Set_Gap)) {
            Project2_DW.is_ACC_ON_MODE = IN_LeadVehicle_Detected_Resume;
            Project2_Y.Acceleration_Mode_h = 3U;
          } else if ((LeadVehicle_Detected == 0) || (DriveVehicle_Speed <=
                      Set_Speed)) {
            Project2_DW.is_ACC_ON_MODE = IN_LeadVehicle_Not_Detected_Res;
            Project2_Y.Acceleration_Mode_h = 1U;
          } else if (((LeadVehicle_Speed < Set_Speed) && (LeadVehicle_Speed <
                       DriveVehicle_Speed)) || ((int32_T)rt_roundd_snf(0.75 *
                       (real_T)Set_Gap) == Time_Gap)) {
            Project2_DW.is_ACC_ON_MODE = IN_LeadVehicle_Speed_lessthan_s;
            Project2_Y.Acceleration_Mode_h = 4U;
          }
          break;

         default:
          /* case IN_LeadVehicle_Speed_lessthan_set_speed: */
          Project2_Y.Acceleration_Mode_h = 4U;
          if ((LeadVehicle_Detected == 0) && (DriveVehicle_Speed == Set_Speed))
          {
            Project2_DW.is_ACC_ON_MODE = Pro_IN_LeadVehicle_Not_Detected;
            Project2_Y.Acceleration_Mode_h = 1U;
          } else {
            tmp = (int32_T)rt_roundd_snf((real_T)LeadVehicle_Speed * 1.25);
            tmp_0 = (int32_T)rt_roundd_snf(1.25 * (real_T)Set_Gap);
            if (tmp < 256) {
              tmp_1 = (uint8_T)tmp;
            } else {
              tmp_1 = MAX_uint8_T;
            }

            if (tmp_0 < 256) {
              tmp_2 = (uint8_T)tmp_0;
            } else {
              tmp_2 = MAX_uint8_T;
            }

            if ((tmp_1 >= DriveVehicle_Speed) && ((int32_T)rt_roundd_snf((real_T)
                  LeadVehicle_Speed * 0.75) <= DriveVehicle_Speed) &&
                (DriveVehicle_Speed < Set_Speed) && (Time_Gap <= tmp_2) &&
                (Time_Gap >= (int32_T)rt_roundd_snf(0.75 * (real_T)Set_Gap))) {
              Project2_DW.is_ACC_ON_MODE = IN_LeadVehicle_Speed_equal_set_;
              Project2_Y.Acceleration_Mode_h = 5U;
            }
          }
          break;
        }
      }
      break;

     default:
      /* case IN_ACC_STANDBY_MODE: */
      Project2_Y.Acceleration_Mode_h = 1U;
      if (!CruiseSwitch) {
        Project2_DW.is_c3_Project2 = Project2_IN_ACC_OFF_MODE;
        Project2_Y.Acceleration_Mode_h = 0U;
      } else if (SetSwitch) {
        Project2_DW.is_c3_Project2 = Project2_IN_ACC_ON_MODE;
        Project2_DW.is_ACC_ON_MODE = IN_LeadVehicle_Detected_Follow;
        Project2_Y.Acceleration_Mode_h = 2U;
      }
      break;
    }
  }

  /* End of Chart: '/ACC_logic' */
}

/* Model initialize function */
void Project2_initialize(void)
{
  /* (no initialization code required) */
}

/* Model terminate function */
void Project2_terminate(void)
{
  /* (no terminate code required) */
}

/*
 * File trailer for generated code.
 *
 * [EOF]
 */

Conclusion:

As for the result, I created this Simulink model using the given requirements and I created SLDDfile and changed solver settings and code generation settings, and adding requirements and create a model advisor run and generated an Embedded coder, and generate code using the Build option and view code.