BRAKE DYNAMOMETER BRAKE DYNAMOMETER DEVELOPMENT FOR DREXEL DEVELOPMENT FOR DREXEL

UNIVERSITY FSAE RACE TEAMUNIVERSITY FSAE RACE TEAM

MEM-01MEM-01Dr. Tein-Min TanDr. Tein-Min Tan

Frank DiMentoFrank DiMento Alfredo VitaleAlfredo VitaleAnthony TofaniAnthony Tofani John HenryJohn Henry

What is a Brake What is a Brake Dynamometer?Dynamometer?

A system used to duplicate track A system used to duplicate track braking scenarios in order to analyze braking scenarios in order to analyze a brake system design before the a brake system design before the components are implemented on a components are implemented on a race vehicle.race vehicle.

This piece of machinery can be This piece of machinery can be utilized by all Drexel University race utilized by all Drexel University race teams, including Formula SAE, Sonic teams, including Formula SAE, Sonic Cricket, and Mini Baja. Cricket, and Mini Baja.

Benefits of a Benefits of a DynamometerDynamometer Prototype costs loweredPrototype costs lowered

Flexible testing scheduleFlexible testing schedule No risk to driver or vehicleNo risk to driver or vehicle Quantified performance dataQuantified performance data Example:Example:

2005 Sinusoidal Rotor Design2005 Sinusoidal Rotor Design

Previous WorkPrevious Work

2005 FSAE Brake Team Designed a 2005 FSAE Brake Team Designed a Brake Dynamometer that was not Brake Dynamometer that was not completed.completed.

2006 FSAE Brake Team added a 2006 FSAE Brake Team added a power controller to obtain necessary power controller to obtain necessary three phase power.three phase power.

The dynamometer has never ran The dynamometer has never ran properly and lacks a data acquisition properly and lacks a data acquisition system.system.

Current Drexel Current Drexel DynamometerDynamometer

Problem StatementProblem Statement Drexel SAE lacks the ability to perform in-Drexel SAE lacks the ability to perform in-

house testing on its braking system design; house testing on its braking system design; Prototypes must be complete systems Prototypes must be complete systems tested on completed car.tested on completed car.

Data from test runs of actual system Data from test runs of actual system components would be useful for design, components would be useful for design, including:including: Braking horsepower Braking horsepower Thermal loadsThermal loads Rotor and pad coefficient of frictionRotor and pad coefficient of friction Actual hydraulic operating pressureActual hydraulic operating pressure

Drexel SAE has a dynamometer that is Drexel SAE has a dynamometer that is incomplete and not operational. incomplete and not operational.

Available DynamometersAvailable Dynamometers

Extremely expensiveExtremely expensive

Requires large work Requires large work areaarea

Hard to relocateHard to relocate

Methods of SolutionMethods of Solution

Constraints and Constraints and ChallengesChallenges

Existing PartsExisting Parts We must integrate existing dyno parts. We must integrate existing dyno parts.

CostCost Funding must be allocated to produce product. Funding must be allocated to produce product.

TimeTime Must be completed within the requirements of Must be completed within the requirements of

Senior Design. Senior Design.

SafetySafety Must be safe for operator and environmentMust be safe for operator and environment. .

AdaptabilityAdaptability 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 MassLower Center of Mass Effective Tensioning Effective Tensioning Contained Hydraulic Contained Hydraulic

ActuatorActuator Single Chain Single Chain Secured/Cushioned Secured/Cushioned

FeetFeet

Initial DesignInitial Design

Dynamometer SystemsDynamometer Systems

Dynamometer SystemsDynamometer Systems

CalculationsCalculations

Determine correct sprocket sizes for Determine correct sprocket sizes for desired flywheel, motor, and rotor speedsdesired flywheel, motor, and rotor speeds

Complete Finite Element Analysis of Complete Finite Element Analysis of FrameFrame

Calibrate LabView based on comparison Calibrate LabView based on comparison of measured data and theoretical valuesof measured data and theoretical values Line PressureLine Pressure Coefficient of FrictionCoefficient of Friction Braking Torque and HPBraking Torque and HP

Manufacturability/Manufacturability/FeasibilityFeasibility

Team will require outside resources:Team will require outside resources: Machining operationsMachining operations ToolsTools

Single-unit production does not Single-unit production does not require mass-production methodsrequire mass-production methods

Team covers all necessary skills, Team covers all necessary skills, including welding.including welding.

Calibration and TestingCalibration and Testing Dynamometer will need to be calibrated Dynamometer will need to be calibrated

and tested to ensure accuracyand tested to ensure accuracy As-measured data will be compared to As-measured data will be compared to

hand-calculated values and data published hand-calculated values and data published by component manufacturers (Wilwood, by component manufacturers (Wilwood, etc.)etc.) Coefficient of FrictionCoefficient of Friction Line PressureLine Pressure Net System HPNet System HP

Calibration to be done by tuning values in Calibration to be done by tuning values in LabView simulationLabView simulation

Environmental & Societal Environmental & Societal ImpactsImpacts Brake Fluid ContainmentBrake Fluid Containment

System pressures will be kept within the limits System pressures will be kept within the limits recommended by component manufacturers to recommended by component manufacturers to prevent leakage.prevent leakage.

Operator SafetyOperator Safety Rotating components will spin in excess of Rotating components will spin in excess of

3000 RPM and will be well balanced to prevent 3000 RPM and will be well balanced to prevent vibration and fatigue. Safety guards will be vibration and fatigue. Safety guards will be installed to protect operator and area workers. installed to protect operator and area workers.

We will measure noise levels during machine We will measure noise levels during machine operation to verify that hearing damage will operation to verify that hearing damage will not be a concern.not be a concern.

Project DeliverablesProject Deliverables

An operating Brake Dynamometer An operating Brake Dynamometer System that will be used to System that will be used to determine the following data:determine the following data: System Braking HorsepowerSystem Braking Horsepower Operating and Maximum Temperatures Operating and Maximum Temperatures

and Pressuresand Pressures Pad-Rotor Coefficient of FrictionPad-Rotor Coefficient of Friction

Documentation that includes:Documentation that includes: Standard Operating ProceduresStandard Operating Procedures Maintenance Instructions and ScheduleMaintenance Instructions and Schedule

TimelineTimeline

Economic AnalysisEconomic AnalysisComponent Cost Company

1 DAQ CARD $219.25 National Instruments2 SQUARE TUBING $215.44 McMaster Carr3 FASTENERS $32.50 Home Depot4 GUARDS $80.00 McMaster Carr5 TEMP SENSOR $150.00 Metris Instruments6 PRESS SENSOR $162.50 APG Automation7 LOAD CELL $327.50 Omega Engineering8 OPTICAL ENCODER $0.00 Previously Purchased9 MACHINING $300.00 Drexel / Cygnet Manufacturing

10 FORCE DEVICE MATERIAL $132.00 Hadco Aluminum Supply11 FORCE DEVICE ACTUATOR $259.00 Firgelli Automations12 FORCE DEVICE POWER $57.50 Power Supply Direct13 COMPUTER $459.00 Dell 14 RUBBER FEET $90.00 McMaster Carr15 SPROCKETS $60.55 Martin Sprocket

Project Overall Cost $2,545.24

2007 FSAE Brake Dyno Budget

Cost EffectivenessCost Effectiveness The current dynamometer has already exhausted The current dynamometer has already exhausted

the following funding:the following funding:

$500 – MEM Department Donation to Install Power $500 – MEM Department Donation to Install Power SupplySupply

$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 Thus $3,089$3,089 has been ineffectively spent for a has been ineffectively spent for a machine that is inoperable to date. Granting our machine that is inoperable to date. Granting our funding request will allow us to validate funding request will allow us to validate previous funding by creating a working device previous funding by creating a working device for future SAE teams to use. for future SAE teams to use.

ConclusionsConclusions A Brake Dynamometer is a valuable tool A Brake Dynamometer is a valuable tool

in brake system development. in brake system development. We will deliver a complete and We will deliver a complete and

operational brake dynamometer within operational brake dynamometer within our projected timeline. our projected timeline.

Our dynamometer will be safe for Our dynamometer will be safe for operators and other area workers.operators and other area workers.

We will include documentation We will include documentation explaining operation and maintenance so explaining operation and maintenance so that the dyno may be used for years to that the dyno may be used for years to come. come.

Questions?Questions?