BRAKE DYNAMOMETER DEVELOPMENT FOR DREXEL UNIVERSITY FSAE RACE TEAM MEM-01 Dr. Tein-Min Tan Frank DiMentoAlfredo Vitale Anthony TofaniJohn Henry

What is a Brake Dynamometer? A system used to duplicate track braking scenarios in order to analyze a brake system design before the components are implemented on a race vehicle. A system used to duplicate track braking scenarios in order to analyze a brake system design before the components are implemented on a race vehicle. This piece of machinery can be utilized by all Drexel University race teams, including Formula SAE, Sonic Cricket, and Mini Baja. This piece of machinery can be utilized by all Drexel University race teams, including Formula SAE, Sonic Cricket, and Mini Baja.

Benefits of a Dynamometer Prototype costs lowered Prototype costs lowered Flexible testing schedule Flexible testing schedule No risk to driver or vehicle No risk to driver or vehicle Quantified performance data Quantified performance data Example: Example: 2005 Sinusoidal Rotor Design 2005 Sinusoidal Rotor Design

Previous Work 2005 FSAE Brake Team Designed a Brake Dynamometer that was not completed FSAE Brake Team Designed a Brake Dynamometer that was not completed FSAE Brake Team added a power controller to obtain necessary three phase power FSAE Brake Team added a power controller to obtain necessary three phase power. The dynamometer has never ran properly and lacks a data acquisition system. The dynamometer has never ran properly and lacks a data acquisition system.

Current Drexel Dynamometer

Problem Statement Drexel SAE lacks the ability to perform in-house testing on its braking system design; Prototypes must be complete systems tested on completed car. Drexel SAE lacks the ability to perform in-house testing on its braking system design; Prototypes must be complete systems tested on completed car. Data from test runs of actual system components would be useful for design, including: Data from test runs of actual system components would be useful for design, including: Braking horsepower Braking horsepower Thermal loads Thermal loads Rotor and pad coefficient of friction Rotor and pad coefficient of friction Actual hydraulic operating pressure Actual hydraulic operating pressure Drexel SAE has a dynamometer that is incomplete and not operational. Drexel SAE has a dynamometer that is incomplete and not operational.

Available Dynamometers Extremely expensive Extremely expensive Requires large work area Requires large work area Hard to relocate Hard to relocate

Methods of Solution

Constraints and Challenges Existing Parts We must integrate existing dyno parts. We must integrate existing dyno parts.Cost Funding must be allocated to produce product. Funding must be allocated to produce product.Time Must be completed within the requirements of Senior Design. Must be completed within the requirements of Senior Design.Safety Must be safe for operator and environment. Must be safe for operator and environment.Adaptability Able to test a wide variety of component designs. Able to test a wide variety of component designs.

New Rig Orientation Hydraulic Actuator Old Rig Orientation Lower Center of Mass Lower Center of Mass Effective Tensioning Effective Tensioning Contained Hydraulic Actuator Contained Hydraulic Actuator Single Chain Single Chain Secured/Cushioned Feet Secured/Cushioned Feet Initial Design

Dynamometer Systems

Calculations Determine correct sprocket sizes for desired flywheel, motor, and rotor speeds Determine correct sprocket sizes for desired flywheel, motor, and rotor speeds Complete Finite Element Analysis of Frame Complete Finite Element Analysis of Frame Calibrate LabView based on comparison of measured data and theoretical values Calibrate LabView based on comparison of measured data and theoretical values Line Pressure Line Pressure Coefficient of Friction Coefficient of Friction Braking Torque and HP Braking Torque and HP

Manufacturability/Feasibility Team will require outside resources: Team will require outside resources: Machining operations Machining operations Tools Tools Single-unit production does not require mass- production methods Single-unit production does not require mass- production methods Team covers all necessary skills, including welding. Team covers all necessary skills, including welding.

Calibration and Testing Dynamometer will need to be calibrated and tested to ensure accuracy Dynamometer will need to be calibrated and tested to ensure accuracy As-measured data will be compared to hand-calculated values and data published by component manufacturers (Wilwood, etc.) As-measured data will be compared to hand-calculated values and data published by component manufacturers (Wilwood, etc.) Coefficient of Friction Coefficient of Friction Line Pressure Line Pressure Net System HP Net System HP Calibration to be done by tuning values in LabView simulation Calibration to be done by tuning values in LabView simulation

Environmental & Societal Impacts Brake Fluid Containment Brake Fluid Containment System pressures will be kept within the limits recommended by component manufacturers to prevent leakage. System pressures will be kept within the limits recommended by component manufacturers to prevent leakage. Operator Safety Operator Safety Rotating components will spin in excess of 3000 RPM and will be well balanced to prevent vibration and fatigue. Safety guards will be installed to protect operator and area workers. Rotating components will spin in excess of 3000 RPM and will be well balanced to prevent vibration and fatigue. Safety guards will be installed to protect operator and area workers. We will measure noise levels during machine operation to verify that hearing damage will not be a concern. We will measure noise levels during machine operation to verify that hearing damage will not be a concern.

Project Deliverables An operating Brake Dynamometer System that will be used to determine the following data: An operating Brake Dynamometer System that will be used to determine the following data: System Braking Horsepower System Braking Horsepower Operating and Maximum Temperatures and Pressures Operating and Maximum Temperatures and Pressures Pad-Rotor Coefficient of Friction Pad-Rotor Coefficient of Friction Documentation that includes: Documentation that includes: Standard Operating Procedures Standard Operating Procedures Maintenance Instructions and Schedule Maintenance Instructions and Schedule

Timeline

Economic Analysis

Cost Effectiveness The current dynamometer has already exhausted the following funding: The current dynamometer has already exhausted the following funding: $500 – MEM Department Donation to Install Power Supply $500 – MEM Department Donation to Install Power Supply $350 – ABB Power Controller Donation $350 – ABB Power Controller Donation $839 – DR-06 Design Team Dyno Development Cost $839 – DR-06 Design Team Dyno Development Cost $1400 – DR-05 Design Team Dyno Development Cost $1400 – DR-05 Design Team Dyno Development Cost Thus $3,089 has been ineffectively spent for a machine that is inoperable to date. Granting our funding request will allow us to validate previous funding by creating a working device for future SAE teams to use. Thus $3,089 has been ineffectively spent for a machine that is inoperable to date. Granting our funding request will allow us to validate previous funding by creating a working device for future SAE teams to use.

Conclusions A Brake Dynamometer is a valuable tool in brake system development. A Brake Dynamometer is a valuable tool in brake system development. We will deliver a complete and operational brake dynamometer within our projected timeline. We will deliver a complete and operational brake dynamometer within our projected timeline. Our dynamometer will be safe for operators and other area workers. Our dynamometer will be safe for operators and other area workers. We will include documentation explaining operation and maintenance so that the dyno may be used for years to come. We will include documentation explaining operation and maintenance so that the dyno may be used for years to come.

Questions?