Project 1- Traffic Jam Assistant Feature

Aim: To develop the Traffic Jam Assist feature that can assist driving in highway traffic jams while the host vehicle automatically follows the vehicle ahead.

Objectives:

1. Developing the Traffic Jam Assist feature as per the Requirement Document using MATLAB Simulink.

2. To Follow all the MBD related processes: Requirement Tagging & Traceability, SLDD creation, Configuration Parameter changes,Model Advisor check & Code Generation.

3. To Use Embedded Coder to generate the code.

Traffic Jam Assistant Feature

Introduction to the Feature:

Traffic Jam Assistant is one of the most common feature in Advanced Driver Assistance System. Traffic Jam Assistant helps the driver arrive more relaxed at their destination, even in dense traffic or in traffic jams. As a partially automated comfort function, the system takes over the longitudinal & lateral guidance of the vehicle. This means that the car can drive off, accelerate & brake automatically, as well as steer the vehicle within certain constraints. The driver has to permanently supervise the system & be ready to take over the complete control of the vehicle at any time.

Traffic Jam Assistant system helps to avoid rear end collisions in dense traffic conditions & traffic jams. In Traffic jams, the vehicle takes over driving off, acceleration, braking and steering within same lane.

Basic Working Principle:

Traffic Jam Assistant is based on the sensors and the functionality of the Adaptive Cruise Control (ACC) with stop & go and Lane Keeping Support (LKS). When ACC ‘Stop & Go’ is turned ON, the Traffic Jam Assistant continuously analyses the speed of the surrounding vehicles and compares it with the own driving speed. If the system detects dense traffic or a traffic jam at speeds less than 60 kmph, the driver can activate the functionality by press of a button. The vehicle will now automatically follow the vehicle in front, takes over driving off, acceleration, braking and steering within same lane.

Information regarding the Traffic Jam Assistant will be available to be displayed to the driver in the Instrument Panel Cluster (IPC). The Algorithm which the students need to implement here in this project is predominantly based on IPC units.

Traffic Jam Assist works when you approach traffic and slow to a crawl. With the system on, you can take your foot off the pedals.

Traffic Jam Assist brakes and accelerates the car for you, while maintaining a safe distance from the vehicle in front.

This is essentially a low-speed version of Adaptive Cruise Control.

Adaptive Cruise Control tries to maintain your set speed, but takes other vehicles into account.

Let’s say you set your cruising speed to 90km/h, but the vehicle in front of your car is only doing 80km/h due to traffic.

Adaptive Cruise Control will maintain a safe distance from the vehicle in front. Your car will not travel at 90km/h.

Driving in a traffic jam is always a stressful situation and with this feature, the vehicle estimates the distance from other vehicles and controls acceleration and deceleration whilst holding the vehicle in lane. This means you only have to worry about steering

Advantages:

• Optional front corner radars help to improve detection of vehicles cutting in.
• The driver is required to monitor both surrounding traffic and system status and can override the system at anytime (SAE level 2 automation).
• Traffic Jam Assist's longitudinal, Stop-and-Go control function can manage vehicle speed and help maintain safe distance to the leading vehicle; actuation is performed electronicaly controlled braking systems or integrated brake control in the case of vacuum less braking systems.
• The lateral control function can help maintain vehicle position in the lane; actuation is performed by ZF's well-established, high bandwidth belt drive or column drive electric powered steering products.
• Helps dramatically reduce the efforts and stress of highway driving in congested traffic.
• Helps enhance vehicle and occupant safety.
• Supports collision mitigation or even collision avoidance to help improve road safety.

Problem Statement:

To develop one specific requirement of Traffic Jam Assistant algorithm which would predominantly feature in the IPC algorithm.Please note that the whole Traffic Jam Assistant is a very huge algorithm & only one small part of the logic is implemented here. Idea is to familiarize with concepts of Model Based Development in MATLAB Environment. The Project must be done keeping in mind the following processes & steps.

• This model must be developed in MATLAB Simulink as per MBD guidelines.
• Code Generation Profile must be in Embedded Coder.
• Simulink Data Dictionary must be created for the model & must be linked to the model.
• Model Advisor Report is mandatory & this will be followed by Code Generation.

Input Signals:

Name of the Signal	Data Type	Range
Input_Voltage	uint8	0 - 255
Input_Switch	boolean	0 – 1
Enable_Display	uint8	0 - 255

Output Signal:

Name of the Signal	Data Type	Range
Output_Display	uint8	0 - 255

Calibration Signals:

Name of the Signal	Data Type	Range	Initial Value
VOLTAGE_MINIMUM_RANGE	uint8	0 – 255	30
VOLTAGE_MAXIMUM_RANGE	uint8	0 – 255	50
OFF_MODE	uint8	0 – 255	2
ON_MODE	uint8	0 – 255	1
STANDBY_MODE	uint8	0 – 255	3
INTERRUPT_1	boolean	0 – 1	1
INTERRUPT_2	boolean	0 - 1	1
NO_DISPLAY	uint8	0 – 255	0

Local Signal:

Name of the Signal	Data Type	Range
Optimum_Voltage	boolean	0 - 1

Data Dictionary:

Model:

Subsystem:

Requirement No 1:

• Input Signal “Input_Voltage” is compared against voltage values “VOLTAGE_MINIMUM_RANGE” & “VOLTAGE_MAXIMUM_RANGE”.
• Incoming input signal “Input_Voltage” must be greater than – equal to “VOLTAGE_MINIMUM_RANGE” and less than – equal to “VOLTAGE_MAXIMUM_RANGE”.
• Output signal from here is “Optimum_Voltage” which will be one of the inputs to the subsystem “DisplayUnit”.

Requirement No 2 (DisplayUnit Subsystem):

• Input Signals are “Optimum_Voltage”, “Input_Switch”,“Enable_Display”. Signal “Enable_Display” must be saturated between the range 0 – 7. Output signal from the subsystem is “Output_Display”.
• Input Signal “Enable_Display” is compared against pre – defined set of values in a multiport switch. Total data ports in the multiport switch is 5.
• Multiport switch inputs 1 & 2 is connected to calibration signal “ON_MODE”, Multiport switch inputs 3 & 4 is connected to calibration signal “OFF_MODE” while Multiport switch input 5 is connected to calibration signal “STANDBY_MODE”.
• The output from Multiport switch is connected to the first input port of the Switch block. The third input port of the Switch block is connected to the calibration signal “NO_DISPLAY”.
• Meanwhile NOT value of input signal “Input_Switch” is compared in an AND gate against input signal “Optimum_Voltage” and the output from comparing if calibration signals “INTERRUPT_1” & “INTERRUPT_2” are equal. The output of the AND gate is the second input of the switch block.
• The output from the switch block is “Output_Display”.

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

1.Click on Model Advisor-

2.Then click on Ok-

3.Then Select Modelling standard For MAB

Requirement Tagging & Traceability:

1.To create the Word file for Requirement Tagging in Model.

2.Highlight the contain which we have to tag for subsytem.

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

Code Generation for Model:-

/*
 * File: traffic_jam_assist.c
 *
 * Code generated for Simulink model 'traffic_jam_assist'.
 *
 * Model version                  : 1.1
 * Simulink Coder version         : 9.5 (R2021a) 14-Nov-2020
 * C/C++ source code generated on : Sat Feb 26 11:54:59 2022
 *
 * Target selection: ert.tlc
 * Embedded hardware selection: Intel->x86-64 (Windows64)
 * Code generation objectives: Unspecified
 * Validation result: Not run
 */

#include "traffic_jam_assist.h"
#include "traffic_jam_assist_private.h"

/* Exported data definition */

/* Const memory section */
/* Definition for custom storage class: Const */
const boolean_T INTERRUPT_1 = 1;       /* Referenced by: '<S2>/Constant4' */
const boolean_T INTERRUPT_2 = 1;       /* Referenced by: '<S2>/Constant5' */
const uint8_T NO_DISPLAY = 0U;         /* Referenced by: '<S2>/Constant3' */
const uint8_T OFF_MODE = 2U;           /* Referenced by: '<S2>/Constant1' */
const uint8_T ON_MODE = 1U;            /* Referenced by: '<S2>/Constant' */
const uint8_T STANDBY_MODE = 3U;       /* Referenced by: '<S2>/Constant2' */
const uint8_T VOLTAGE_MAXIMUM_RANGE = 50U;/* Referenced by: '<S3>/Constant1' */
const uint8_T VOLTAGE_MINIMUM_RANGE = 30U;/* Referenced by: '<S3>/Constant' */

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

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

/* Real-time model */
static RT_MODEL_traffic_jam_assist_T traffic_jam_assist_M_;
RT_MODEL_traffic_jam_assist_T *const traffic_jam_assist_M =
  &traffic_jam_assist_M_;

/* Model step function */
void traffic_jam_assist_step(void)
{
  real_T tmp;

  /* Switch: '<S2>/Switch' incorporates:
   *  Constant: '<S2>/Constant4'
   *  Constant: '<S2>/Constant5'
   *  Constant: '<S3>/Constant'
   *  Constant: '<S3>/Constant1'
   *  Inport: '<Root>/Input_Switch'
   *  Inport: '<Root>/Input_Voltage'
   *  Logic: '<S2>/AND'
   *  Logic: '<S2>/AND1'
   *  Logic: '<S2>/NOT'
   *  Logic: '<S3>/AND'
   *  RelationalOperator: '<S2>/Relational Operator'
   *  RelationalOperator: '<S3>/Relational Operator'
   *  RelationalOperator: '<S3>/Relational Operator1'
   */
  if ((!traffic_jam_assist_U.Input_Switch) &&
      ((traffic_jam_assist_U.Input_Voltage >= VOLTAGE_MINIMUM_RANGE) &&
       (traffic_jam_assist_U.Input_Voltage <= VOLTAGE_MAXIMUM_RANGE)) &&
      (INTERRUPT_1 == INTERRUPT_2)) {
    /* Saturate: '<S2>/Saturation' incorporates:
     *  Inport: '<Root>/Enable_Display'
     */
    if (traffic_jam_assist_U.Enable_Display > 0.5) {
      tmp = 0.5;
    } else if (traffic_jam_assist_U.Enable_Display < -0.5) {
      tmp = -0.5;
    } else {
      tmp = traffic_jam_assist_U.Enable_Display;
    }

    /* End of Saturate: '<S2>/Saturation' */

    /* MultiPortSwitch: '<S2>/Multiport Switch' */
    if ((int32_T)tmp == 1) {
      /* Outport: '<Root>/Output_Display' incorporates:
       *  Constant: '<S2>/Constant'
       */
      traffic_jam_assist_Y.Output_Display = ON_MODE;
    } else {
      /* Outport: '<Root>/Output_Display' incorporates:
       *  Constant: '<S2>/Constant2'
       */
      traffic_jam_assist_Y.Output_Display = STANDBY_MODE;
    }

    /* End of MultiPortSwitch: '<S2>/Multiport Switch' */
  } else {
    /* Outport: '<Root>/Output_Display' incorporates:
     *  Constant: '<S2>/Constant3'
     */
    traffic_jam_assist_Y.Output_Display = NO_DISPLAY;
  }

  /* End of Switch: '<S2>/Switch' */
}

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

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

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

/*
 * File: traffic_jam_assist.h
 *
 * Code generated for Simulink model 'traffic_jam_assist'.
 *
 * Model version                  : 1.1
 * Simulink Coder version         : 9.5 (R2021a) 14-Nov-2020
 * C/C++ source code generated on : Sat Feb 26 11:54:59 2022
 *
 * Target selection: ert.tlc
 * Embedded hardware selection: Intel->x86-64 (Windows64)
 * Code generation objectives: Unspecified
 * Validation result: Not run
 */

#ifndef RTW_HEADER_traffic_jam_assist_h_
#define RTW_HEADER_traffic_jam_assist_h_
#ifndef traffic_jam_assist_COMMON_INCLUDES_
#define traffic_jam_assist_COMMON_INCLUDES_
#include "rtwtypes.h"
#endif                                 /* traffic_jam_assist_COMMON_INCLUDES_ */

#include "traffic_jam_assist_types.h"

/* Macros for accessing real-time model data structure */
#ifndef rtmGetErrorStatus
#define rtmGetErrorStatus(rtm)         ((rtm)->errorStatus)
#endif

#ifndef rtmSetErrorStatus
#define rtmSetErrorStatus(rtm, val)    ((rtm)->errorStatus = (val))
#endif

/* External inputs (root inport signals with default storage) */
typedef struct {
  uint8_T Input_Voltage;               /* '<Root>/Input_Voltage' */
  boolean_T Input_Switch;              /* '<Root>/Input_Switch' */
  real_T Enable_Display;               /* '<Root>/Enable_Display' */
} ExtU_traffic_jam_assist_T;

/* External outputs (root outports fed by signals with default storage) */
typedef struct {
  uint8_T Output_Display;              /* '<Root>/Output_Display' */
} ExtY_traffic_jam_assist_T;

/* Real-time Model Data Structure */
struct tag_RTM_traffic_jam_assist_T {
  const char_T * volatile errorStatus;
};

/* External inputs (root inport signals with default storage) */
extern ExtU_traffic_jam_assist_T traffic_jam_assist_U;

/* External outputs (root outports fed by signals with default storage) */
extern ExtY_traffic_jam_assist_T traffic_jam_assist_Y;

/* Model entry point functions */
extern void traffic_jam_assist_initialize(void);
extern void traffic_jam_assist_step(void);
extern void traffic_jam_assist_terminate(void);

/* Exported data declaration */

/* Const memory section */
/* Declaration for custom storage class: Const */
extern const boolean_T INTERRUPT_1;    /* Referenced by: '<S2>/Constant4' */
extern const boolean_T INTERRUPT_2;    /* Referenced by: '<S2>/Constant5' */
extern const uint8_T NO_DISPLAY;       /* Referenced by: '<S2>/Constant3' */
extern const uint8_T OFF_MODE;         /* Referenced by: '<S2>/Constant1' */
extern const uint8_T ON_MODE;          /* Referenced by: '<S2>/Constant' */
extern const uint8_T STANDBY_MODE;     /* Referenced by: '<S2>/Constant2' */
extern const uint8_T VOLTAGE_MAXIMUM_RANGE;/* Referenced by: '<S3>/Constant1' */
extern const uint8_T VOLTAGE_MINIMUM_RANGE;/* Referenced by: '<S3>/Constant' */

/* Real-time Model object */
extern RT_MODEL_traffic_jam_assist_T *const traffic_jam_assist_M;

/*-
 * The generated code includes comments that allow you to trace directly
 * back to the appropriate location in the model.  The basic format
 * is <system>/block_name, where system is the system number (uniquely
 * assigned by Simulink) and block_name is the name of the block.
 *
 * Use the MATLAB hilite_system command to trace the generated code back
 * to the model.  For example,
 *
 * hilite_system('<S3>')    - opens system 3
 * hilite_system('<S3>/Kp') - opens and selects block Kp which resides in S3
 *
 * Here is the system hierarchy for this model
 *
 * '<Root>' : 'traffic_jam_assist'
 * '<S1>'   : 'traffic_jam_assist/Traffic Jam Assist'
 * '<S2>'   : 'traffic_jam_assist/Traffic Jam Assist/DisplayUnit'
 * '<S3>'   : 'traffic_jam_assist/Traffic Jam Assist/InputVoltage'
 */
#endif                                 /* RTW_HEADER_traffic_jam_assist_h_ */

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