Project 2-Highway Assistant-Lane Changing Assistant

Highway Assistant – Lane Changing Assistant

Introduction to the Feature:

The Highway Assistant supports the driver and takes over the longitudinal and lateral guidance of the vehicle in monotonous driving situations on highways. The partially automated function can automatically start, accelerate, brake as well as steer the vehicle to a certain extent. The driver has to permanently supervise the system and be ready to take over the complete control of the vehicle at any time.

Drivers are taught to assess surrounding traffic before changing lanes by checking their rearview and side mirrors and looking over each shoulder. However, even for those who follow this sequence of checks, the vehicle's blind spot – the area alongside and just behind the vehicle – is a constant source of danger and often the cause of serious accidents. Even vehicles approaching quickly from behind can pose a risk. To make changing lanes safer, this feature has been developed.

Basic Working Principle:

Highway Assistant is a partially automated driving function for a speed range of up to 180 km/h (112 mph) on highways. It combines the radar-based longitudinal guidance of Adaptive Cruise Control (ACC) with the video-based lateral guidance of lane keeping support in one system. Highway Assistant can be supplemented by an automatic lane change initiated and monitored by the driver in a speed range of 60 – 130 km/h (35 – 80 mph).

The lane Change Assistant works by using two mid-range radar sensors that are concealed in the rear bumper – one on the left, one on the right. These two sensors monitor the area alongside and behind the car. Powerful control software collates the sensor information to create a complete picture of all traffic in the area behind the vehicle.Whenever another vehicle approaches at speed from behind or is already present in the blind spot, a signal such as a warning light in the side mirror alerts the driver to the hazard. Should the driver still activate the turn signal with the intention of changing lanes, the system issues an additional acoustic and/or haptic warning.

Problem Statement:

To develop one specific requirement of Highway Assistant – Lane Changing Assistant algorithm. Please note that the whole Highway Assistant – Lane Changing Assistant is a very huge algorithm & only one small part of the logic is implemented here. Idea is to familiarize with concepts of Autosar Software Component Development in MATLAB Environment by following the Model Based Development guidelines. The Project must be done keeping in mind the following processes & steps.

• This model must be developed in MATLAB Simulink per MBD guidelines.
• Code Generation Profile must be Autosar Coder.
• Simulink Data Dictionary must be created for the model & must be linked to the model.
• All the input & output signals must be mapped into the Autosar Editor.
• Model Advisor Report is mandatory & this will be followed by Code Generation.

Input Signals:

Name of the Signal	Data Type	Range
Highway_Input_Signal	uint8	0 - 255
Enable_Display	uint8	0 – 255
Input_Switch	uint8	0 – 255
Lane_Input_Signal	uint8	0 - 255

Local Signals:

Name of the Signal	Data Type	Range
Highway_Display_Mode_1	uint8	0 - 255
Highway_Display_Mode_2	uint8	0 – 255
Highway_Display_Mode_3	uint8	0 – 255
Highway_Display_Mode_4	uint8	0 – 255
Lane_Display_Mode_1	uint8	0 – 255
Lane_Display_Mode_2	uint8	0 – 255
Lane_Display_Mode_3	uint8	0 – 255
Lane_Display_Mode_4	uint8	0 – 255

Output Signals:

Name of the Signal	Data Type	Range
Display_Mode_1	uint8	0 - 255
Display_Mode_2	uint8	0 – 255
Display_Mode_3	uint8	0 – 255
Display_Mode_4	uint8	0 - 255

The sldd file is created for all the signals mentioned above as shown:

Below diagram shows the main simulink model build according to the requirement:

• The above simulation model is created according to the requirement.

• The subsystem of the model is shown above.
• It contains the three subsystems of the Requirement 1, Requirement 2 and Requirement 3.

Process of building the required model:

• First we have to create the sldd file.
• For that go into the modelling tab of the task bar.
• Under design category there is the Link to Data Dictionary option and then click on it.

• It will open a model parameter properties window.
• The by clicking on the new option, 'Data.sldd' file is created.
• Uncheck the 'Enable model access to base workspace' by doing this the data will not stored in the base workspace.

• Then open the model explorer from the same design category of modelling tab.
• In the model hierarchy of model workspace, the new tab of the external data is created.
• Then in the design option of the external data we have to add all the signals and parameters of the model.

• Then in the model explorer all the simulink signals are added.
• The minimum and maximum value, data type, storage class are given for the respective signal.
• The storage class for input signal, local signal and output signals is given as Auto for the Autosar Port mapping.

Requirement No 1 [Highway_DisplayUnit]:

Inputs to this particular subsystem are “Highway_Input_Signal”, “Enable_Display”, “Input_Switch”. These three input signals, when assigned to a particular value will give output signals of specific value. The output signals are “Highway_Display_Mode_1”, “Highway_Display_Mode_2”, “Highway_Display_Mode_3”, “Highway_Display_Mode_4”. The requirement must be implemented in the form of a Stateflow logic.

Condition	Action
Highway_Input_Signal = 1 Enable_Display = off Input_Switch = on	Highway_Display_Mode_1 = 232 Highway_Display_Mode_2 = 183 Highway_Display_Mode_3 = 41 Highway_Display_Mode_4 = 94
Highway_Input_Signal = 1 Enable_Display = on Input_Switch = on	Highway_Display_Mode_1 = 213 Highway_Display_Mode_2 = 183 Highway_Display_Mode_3 = 9 Highway_Display_Mode_4 = 94

The subsystem given below is created for the requirement 1:

• It contains the flowchart for the logic that will be implemented.

• The above logic implemented as per the data given in the table.

Requirement No 2 [Lane_DisplayUnit]:

Inputs to this particular subsystem are “Enable_Display”, “Input_Switch”, “Lane_Input_Signal”. These three input signals, when assigned to a particular value will give output signals of specific value. The output signals are “Lane_Display_Mode_1”, “Lane_Display_Mode_2”, “Lane_Display_Mode_3”, “Lane_Display_Mode_4”. The requirement must be implemented in the form of Stateflow logic.

Condition	Action
Lane_Input_Signal= 6 Enable_Display = off Input_Switch = on	Lane_Display_Mode_1 = 132 Lane_Display_Mode_2 = 185 Lane_Display_Mode_3 = 54 Lane_Display_Mode_4 = 67
Lane_Input_Signal= 6 Enable_Display = on Input_Switch = on	Lane_Display_Mode_1 = 127 Lane_Display_Mode_2 = 248 Lane_Display_Mode_3 = 186 Lane_Display_Mode_4 = 84

The subsystem given below is created for the requirement 2:

• It contains the flowchart for the logic that will be implemented.

• The above logic implemented as per the data given in the table.

Requirement No 3:

Signals coming from both subsystems “Highway_Display_Mode_1” & “Lane_Display_Mode_1” are given as inputs to a switch block which will have input signal “Highway_Input_Signal” given as 2^nd input to the switch block. Corresponding output from this particular switch block is output signal “Display_Mode_1”.

Signals coming from both subsystems “Highway_Display_Mode_2” & “Lane_Display_Mode_2” are given as inputs to a switch block which will have input signal “Highway_Input_Signal” given as 2^nd input to the switch block. Corresponding output from this particular switch block is output signal “Display_Mode_2”.

Signals coming from both subsystems “Highway_Display_Mode_3” & “Lane_Display_Mode_3” are given as inputs to a switch block which will have input signal “Highway_Input_Signal” given as 2^nd input to the switch block. Corresponding output from this particular switch block is output signal “Display_Mode_3”.

Signals coming from both subsystems “Highway_Display_Mode_4” & “Lane_Display_Mode_4” are given as inputs to a switch block which will have input signal “Highway_Input_Signal” given as 2^nd input to the switch block. Corresponding output from this particular switch block is output signal “Display_Mode_4”.

The subsystem given below is created for the requirement 3:

• The above simulink model is build ae per the requirements.

• In the configuration parameter, solver type is selected as Fixed-step.
• The solver is selected as discrete (no-continuous states).
• And the sample time is auto as per the requirement.

• Then in the code generation, System target file is selected as autosar.tlc

• In the coverage section, Enable coverage analysis is selected by checking the box.
• The structural coverage level is selected as Modified Condition Decision Coverage (MCDC).
• This will check for the total execution of the system during the simution of the model.

• Then all the subsystems of the requirements are tagged with the respective requirements.
• For that first open the word file containing all the details of the model.
• Then select the word requirement in the word file.
• After that right click on the subsystem of the requirement block.
• Then in the requirement section click on the Link to Selection in word.
• After that Requirement 1-Lead_Vehicle will appear in the requirement section as above.
• The same procedure is applied to the all other requirement block.

• In the modelling section click on the Model Advisor for generating the MAAB guidlines report.
• Select the model system for the report generation.
• After opening the new window, select the Modelling Standards for MAB in the by task section.
• After clicking on the Run Selected Checks, the summary of the report is generated showing the total pass cases, fail cases and the warnings.

• For configuration of the parameters click on the orange block.

• First all the XML options are configured as seen.

• All the input and the output signals are added into the S-R Interface.

• The rennables are created by adding the initialization signal and the event signals.

• The input signals are added in the receiver Ports.

• The output signals are added in the sender ports.

• Finally the validation is done and it is successfully validated.

• For the Autosar code generation, click on the Quick Start option in the Autosar section.

• By the Quick start option the window like this will appear, we have to click next in the window for all the options and it will validate the requirement for the Autosar code generation.
• And finally after validation it starts the process of the code generation.

• If we click on the perticular block name in the C code then this block will appear on the screen with the blue colour this is called the traceability.

Finally the code is generated for the require model as ahown:

/*
* File: Lane_Change_Assistance.c
*
* Code generated for Simulink model 'Lane_Change_Assistance'.
*
* Model version : 1.35
* Simulink Coder version : 9.5 (R2021a) 14-Nov-2020
* C/C++ source code generated on : Mon Apr 18 18:41:52 2022
*
* Target selection: autosar.tlc
* Embedded hardware selection: Intel->x86-64 (Windows64)
* Code generation objectives:
* 1. Execution efficiency
* 2. RAM efficiency
* Validation result: Not run
*/

#include "Lane_Change_Assistance.h"

/* Named constants for Chart: '<S2>/Chart' */
#define IN_Condition_1 ((uint8)1U)
#define IN_Condition_2 ((uint8)2U)

/* Block signals and states (default storage) */
DW rtDW;

/* Model step function */
void Lane_Change_Assistance_ms(void)
{
sint32 tmp;
uint8 rtb_Highway_Display_Mode_1;
uint8 rtb_Highway_Display_Mode_3;
uint8 rtb_Lane_Display_Mode_1;
uint8 rtb_Lane_Display_Mode_2;
uint8 rtb_Lane_Display_Mode_3;
uint8 rtb_Lane_Display_Mode_4;

/* Chart: '<S2>/Chart' incorporates:
* Inport: '<Root>/Enable_Display'
* Inport: '<Root>/Highway_Input_Signal'
* Inport: '<Root>/Input_Switch'
*/
if (rtDW.is_active_c3_Lane_Change_Assistance == 0U) {
rtDW.is_active_c3_Lane_Change_Assistance = 1U;
rtDW.is_c3_Lane_Change_Assistance = IN_Condition_1;
rtb_Highway_Display_Mode_1 = 232U;
rtb_Highway_Display_Mode_3 = 41U;
} else if (rtDW.is_c3_Lane_Change_Assistance == IN_Condition_1) {
rtb_Highway_Display_Mode_1 = 232U;
rtb_Highway_Display_Mode_3 = 41U;
if ((Rte_IRead_Lane_Change_Assistance_ms_Rp_Highway_Input_Signal_DE_Highway_Input_Signal
() == 1) &&
(Rte_IRead_Lane_Change_Assistance_ms_Rp_Enable_Display_DE_Enable_Display
() == 1) &&
(Rte_IRead_Lane_Change_Assistance_ms_Rp_Input_Switch_DE_Input_Switch() ==
1)) {
rtDW.is_c3_Lane_Change_Assistance = IN_Condition_2;
rtb_Highway_Display_Mode_1 = 213U;
rtb_Highway_Display_Mode_3 = 9U;
}
} else {
/* case IN_Condition_2: */
rtb_Highway_Display_Mode_1 = 213U;
rtb_Highway_Display_Mode_3 = 9U;
if ((Rte_IRead_Lane_Change_Assistance_ms_Rp_Highway_Input_Signal_DE_Highway_Input_Signal
() == 1) &&
(Rte_IRead_Lane_Change_Assistance_ms_Rp_Enable_Display_DE_Enable_Display
() == 0) &&
(Rte_IRead_Lane_Change_Assistance_ms_Rp_Input_Switch_DE_Input_Switch() ==
1)) {
rtDW.is_c3_Lane_Change_Assistance = IN_Condition_1;
rtb_Highway_Display_Mode_1 = 232U;
rtb_Highway_Display_Mode_3 = 41U;
}
}

/* End of Chart: '<S2>/Chart' */

/* Chart: '<S3>/Chart' incorporates:
* Inport: '<Root>/Enable_Display'
* Inport: '<Root>/Input_Switch'
* Inport: '<Root>/Lane_Input_Signal'
*/
if (rtDW.is_active_c1_Lane_Change_Assistance == 0U) {
rtDW.is_active_c1_Lane_Change_Assistance = 1U;
rtDW.is_c1_Lane_Change_Assistance = IN_Condition_1;
rtb_Lane_Display_Mode_1 = 132U;
rtb_Lane_Display_Mode_2 = 185U;
rtb_Lane_Display_Mode_3 = 54U;
rtb_Lane_Display_Mode_4 = 67U;
} else if (rtDW.is_c1_Lane_Change_Assistance == IN_Condition_1) {
rtb_Lane_Display_Mode_1 = 132U;
rtb_Lane_Display_Mode_2 = 185U;
rtb_Lane_Display_Mode_3 = 54U;
rtb_Lane_Display_Mode_4 = 67U;
if ((Rte_IRead_Lane_Change_Assistance_ms_Rp_Lane_Input_Signal_DE_Lane_Input_Signal
() == 6) &&
(Rte_IRead_Lane_Change_Assistance_ms_Rp_Enable_Display_DE_Enable_Display
() == 1) &&
(Rte_IRead_Lane_Change_Assistance_ms_Rp_Input_Switch_DE_Input_Switch() ==
1)) {
rtDW.is_c1_Lane_Change_Assistance = IN_Condition_2;
rtb_Lane_Display_Mode_1 = 127U;
rtb_Lane_Display_Mode_2 = 248U;
rtb_Lane_Display_Mode_3 = 186U;
rtb_Lane_Display_Mode_4 = 84U;
}
} else {
/* case IN_Condition_2: */
rtb_Lane_Display_Mode_1 = 127U;
rtb_Lane_Display_Mode_2 = 248U;
rtb_Lane_Display_Mode_3 = 186U;
rtb_Lane_Display_Mode_4 = 84U;
if ((Rte_IRead_Lane_Change_Assistance_ms_Rp_Lane_Input_Signal_DE_Lane_Input_Signal
() == 6) &&
(Rte_IRead_Lane_Change_Assistance_ms_Rp_Enable_Display_DE_Enable_Display
() == 0) &&
(Rte_IRead_Lane_Change_Assistance_ms_Rp_Input_Switch_DE_Input_Switch() ==
1)) {
rtDW.is_c1_Lane_Change_Assistance = IN_Condition_1;
rtb_Lane_Display_Mode_1 = 132U;
rtb_Lane_Display_Mode_2 = 185U;
rtb_Lane_Display_Mode_3 = 54U;
rtb_Lane_Display_Mode_4 = 67U;
}
}

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

/* Switch: '<S4>/Switch' incorporates:
* Inport: '<Root>/Highway_Input_Signal'
* Switch: '<S4>/Switch1'
* Switch: '<S4>/Switch2'
*/
tmp =
Rte_IRead_Lane_Change_Assistance_ms_Rp_Highway_Input_Signal_DE_Highway_Input_Signal
();
if (tmp != 0) {
/* Outport: '<Root>/Display_Mode_1' */
Rte_IWrite_Lane_Change_Assistance_ms_Pp_Display_Mode_1_DE_Display_Mode_1
(rtb_Highway_Display_Mode_1);
rtb_Lane_Display_Mode_2 = 183U;
} else {
/* Outport: '<Root>/Display_Mode_1' */
Rte_IWrite_Lane_Change_Assistance_ms_Pp_Display_Mode_1_DE_Display_Mode_1
(rtb_Lane_Display_Mode_1);
}

/* End of Switch: '<S4>/Switch' */

/* Outport: '<Root>/Display_Mode_2' */
Rte_IWrite_Lane_Change_Assistance_ms_Pp_Display_Mode_2_DE_Display_Mode_2
(rtb_Lane_Display_Mode_2);

/* Switch: '<S4>/Switch2' incorporates:
* Switch: '<S4>/Switch3'
*/
if (tmp != 0) {
/* Outport: '<Root>/Display_Mode_3' */
Rte_IWrite_Lane_Change_Assistance_ms_Pp_Display_Mode_3_DE_Display_Mode_3
(rtb_Highway_Display_Mode_3);
rtb_Lane_Display_Mode_4 = 94U;
} else {
/* Outport: '<Root>/Display_Mode_3' */
Rte_IWrite_Lane_Change_Assistance_ms_Pp_Display_Mode_3_DE_Display_Mode_3
(rtb_Lane_Display_Mode_3);
}

/* Outport: '<Root>/Display_Mode_4' */
Rte_IWrite_Lane_Change_Assistance_ms_Pp_Display_Mode_4_DE_Display_Modde_4
(rtb_Lane_Display_Mode_4);
}

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

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