Prior to 2024, our team lacked validated data or calculations to justify the sizing of our hydraulic brake components, including the master cylinders, calipers, and pedal ratio. Component choices were largely based on convenience, past experience, or assumptions, which introduced uncertainty in performance and brake balance.
To solve this, I developed a custom MATLAB model to simulate the full braking system and optimize its component sizing.
Problem:
The team had never previously modeled or validated the mechanical or hydraulic relationships between the master cylinders and the calipers. As a result…
- Brake torque and pressure at maximum deceleration was unknown
- Minimal pedal travel and very stiff pedal feel
- No analysis had been done to ensure 4-wheel lockup, putting vehicle stability at risk
Solution:
I built a MATLAB script that modeled the entire brake system from pedal input to wheel torque. The code accepted a wide range of vehicle and system parameters to simulate how pedal force translates into hydraulic pressure, clamp force, brake torque, pedal travel, pedal force, and ultimately vehicle deceleration.
Inputs Included:
- Vehicle Parameters – Mass, wheelbase, CG height, axle loads, tire μ, and wheel radius
- Pedal Geometry – Pedal ratio, balance bar position, and expected driver force
- Hydraulic Circuit – Master cylinder bores, line pressure, and compliance
- Brake Components – Caliper piston areas, pad μ, and effective rotor radius
The Model Output:
- Clamping Force vs. Caliper Piston Area
- Clamping Force vs. Pedal Ratio
- Line Pressure vs. Master Cylinder Bore Size
- Pedal Travel vs. Master Cylinder Bore Size
Design Decisions Informed:
The MATLAB tool allowed me to systematically size and select components rather than guess:
I added a bias tuning bar for drivers to see in the dashboard, giving us control over the brake feel and performance depending on track grip and driver preference.
I selected master cylinder bores and a pedal ratio that provided enough line pressure to reach our target deceleration, while keeping pedal force within comfortable limits for all drivers.
I validated the caliper piston areas and rotor geometry to ensure we could generate the required wheel torque without exceeding pressure limits or the pad’s usable friction range.
