Project 1- Traffic Jam Assistant Feature

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.

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

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”.

 ANS:

THEORY

   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 km / h, the driver can activate the functionality with the press of a button. The vehicle will now automatically follow the vehicle in front, takes over driving off, accelerating, braking, and steering within the 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 Assistant is one of the most common features in the 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.
• The 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 the same lane.
• 

   AIM:

• Model Development of a single feature of Traffic Jam Assist using MATLAB & Simulink as well as Code Generation using Embedded Coder.
• Step-1: Model Development:
• Now we have to develop the model as per the requirement.
• The model is spilt into two requirements.

• 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”.
• 
• The entire model looks like below:
• 
• 
• Step-2: SLDD-Simulink data dictionary.
• After developing the model we have to create SLDD( Simulink data dictionary).
• 
• To create SLDD go to modelling tab -> in modelling settings: select modelling properties -> in external data -> select new : give name -> apply -> ok. And then link to model.
• It looks like below:
• 
• Step-3: Signal resolving and propogation:
• The input and output  signals must be resolved and passing signals must be propogated.
• Step -4: Configuration settings:
• Before performing code generation and model advisor report we need to make some settings in the Configuration settings.

change system target file:ert.tlc Embedded coder in Code generation.

Step -5: Model advisor report:

To perform Model advisor checks go to modelling -> select mdel advisor.

select model name -> click on ok

After selecting Modelling standards for JMAAB -> click on RUN.

Here, pass conditions : 107, fail :0 , warning :18.

Click on Generate report: the report looks like below:

•  Generate report:
• 
• Step - 6: Code generation:
• To generate code we need to change system target file as ert.tlc -Embedded coder as per the requireement.
• 
• goto apps -> select Embedded coder ->  In C Code -> click on Build. the code generated at back end.
• 
• The code looks like below:
• Successfully conducted model build and generated code. The generated codes and files can be seen in the current directory.

generated report:

ert.tlc: code

.c and .h files also created:

CONCLUSION

• Developed a Model of a single feature of Traffic Jam Assist as per MAAB guidelines as well as created Simulink Data Dictionary using MATLAB & Simulink. Generated a code using Embedded Coder and generated a Model Advisor Report.