Date of Award


Access Type

Thesis - Open Access

Degree Name

Master of Science in Mechanical Engineering


Mechanical Engineering

Committee Chair

Patrick N. Currier, Ph.D.

First Committee Member

Marc Compere, Ph.D.

Second Committee Member

Darris L. White, Ph.D.


As the world continues to move further away from our reliance on fossil fuels, hybrid vehicles are becoming ever more popular. Braking is a system on both hybrid and normal vehicles that involves a significant amount of power and energy. A hybrid can recapture some of that energy using regenerative braking. In this thesis, a method is devised to blend hydraulic and regenerative braking in the most effective manner. A MATLAB Simulink model was built to simulate a parallel-series plug-in hybrid electric vehicle. The model allows for the implementation of a regenerative brake controller that utilizes floating pedal regen, custom shift logic, and brake pedal blended regen. The floating pedal controller activates regenerative braking when the driver releases the accelerator pedal. This is done by remapping the pedal based on vehicle speed, gear position, and wheel torques. The custom shift logic utilizes the motor rpm and efficiencies curves to determine when to shift the transmission. The brake pedal regen is added to the hydraulic braking based on brake pedal position. This regenerative brake controller can recharge the battery by 2% SOC during one deceleration event from 130 kph to 20 kph, while maintaining a comfortable deceleration rate less than 3m/sec^2.