ABS Control System Simulation (Pacejka Tire Model)

This repository contains a MATLAB/Simulink implementation of an Anti-lock Braking System (ABS). The simulation focuses on the longitudinal dynamics of a vehicle during a hard braking maneuver, utilizing the Pacejka "Magic Formula" to accurately model the friction interface between the tire and the road.

📋 Project Overview

The goal of this system is to prevent wheel lock-up by modulating braking torque, maintaining the Slip Ratio ($\lambda$) within an optimal range where the friction coefficient ($\mu$) is at its peak.

Key Features:

• Pacejka Tire Model: Realistic tire-road interaction using non-linear equations.
• Hydraulic Dynamics: Modeling of hydraulic resistance ($R_h$) and compliance ($C_h$).
• Simulink Integration: A modular block diagram approach for control logic testing.
• Automated Plotting: A Live Script (Vars.mlx) for parameter initialization and post-simulation analysis.

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⚙️ Physical Parameters

The simulation is configured with the following default values (editable in Vars.mlx):

Category	Variable	Value	Description
Hydraulic	$R_h$	0.1	Hydraulic Resistance
	$C_h$	0.1	Hydraulic Compliance
Vehicle	$m_v$	1200 kg	Vehicle Mass
	$v_0$	28 m/s	Initial Speed (~100 km/h)
	$R_w$	0.28 m	Wheel Radius
Pacejka	A, B, C, D	Custom	Shape factors for the $\mu$-slip curve

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🚀 How to Run

1. Clone the repository:

   git clone https://github.com/AntoineBert/GNSS-Positioning-And-Signal-Analysis.git```

2. Initialize Variables: Open MATLAB and run the Vars.mlx script. This loads all constants into the Workspace.
3. Open Model: Open the ABS_Simulink_Model.slx file.
4. Simulate: Click the Run button in the Simulink toolstrip.
5. Analyze: Return to the Vars.mlx window to view the generated subplots and performance analysis.

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📊 Results and Analysis

The simulation generates four key performance indicators via subplot:

1. Brake Torque: Visualizes the pressure modulation by the ABS controller.
2. Distance: Compares the stopping distance of the vehicle vs. the theoretical wheel distance.
3. Speed: Shows the synchronization between vehicle speed and wheel speed.
4. Slip Ratio: Monitors the controller's ability to stay near the Pacejka curve peak.

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🛠 Tech Stack

• MATLAB (R2020b or later recommended)
• Simulink
• Control System Toolbox

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📝 License

This project is licensed under the MIT License - see the LICENSE file for details.

📧 Contact

AntoineBert - GitHub Profile