P16221 – FSAE Shock DynamometerProblem Definition Review

• Aung Toe – EE• Jim Holmes – EE

– Project Manager

• Sal Fava – ME– Chief Engineer

• Chris Batorski – ME– Facilitator

• Andrew Dodd – ISE

P16221 – MSD Team

• RIT Formula SAE (FSAE) develops an open-wheel single seat race car for the Formula SAE collegiate design series.

• One of the more complicated parts of the car that the team does not produce in-house is the dampers.

• While the springs in the suspension are sensitive to displacement, shock absorbers (dampers) are used to control the relative velocity between the wheels and chassis.

Project Background

Dampers can be very hard to understand• Very nonlinear, with different damper shaft speeds

controlling different aspects of the car. • Speed dependent, and affected by temperature, air

pressure, etc. • Having the ability to test the dampers in-house

would open a lot of opportunities for tuning and testing the car not currently available to the FSAE team.

Project Background

Current State• A shock dynamometer is a measurement device that

can supply an input and measure the response (both displacement and force) of a damper.

• Similar machines in the mechanical engineering building labs do not meet the frequency requirements, size constraints, and mobility requirements.

Problem Statement

Desired State• The goal is to design a device that is better equipped for shock

measurements– Analyze closest in house solution (Instron 8801 in

Mechanics Lab)• Larger eye to eye distance• Input track data• Faster control speeds• Customizable user interface• Save data in a common format

Problem Statement

• Actuation Type– Actuator

• EMA• Hydraulic• Air

– Cam• Motor driven

Dynamometer Solutions

Example of Track data

Standard Performance Chart

Desired Output Chart

Use Scenarios

1. Cost less than $4,0002. Able to be moved in the shop easily3. Reproduce damper displacements from track data4. Measure damper forces5. Measure damper shaft position6. Measure damper temperature during test7. Save and recall test data for post processing8. Maximum footprint of 4’ x 4’9. Accommodate wide range of damper sizes

Customer Performance Requirements

Stakeholders

• RIT Formula SAE Team– Customer and End users– Want a working, affordable and user friendly Shock Dyno

• Dr. Alan Nye (Formula Team Advisor)– Concerned with development and funding

• RIT and KGCOE– Potential end users– Provide space for Dyno– Fabrication support

• Calibration Team– Who will calibrate the stand when necessary?

• Local External companies– Potential end users/sponsors

Key Engineering Requirements

• Input – Displacement (inches) and time (sec) profile (cam profile

or a course map) >100Hz control frequency

• Record:– Force (max 2500lb)– Distance (.25-7in)– Time (s) – Temperature (150˚C max)

Key Engineering Requirements Cont’d

• Binary Requirements – must meet customer user approval– Save all data so it can be easily processed externally– Easily customized real time data display

• Safety Requirements– Fully enclosed test area– Emergency stop switch

• Budget– Senior Design Donation $500– Additional Funding TBD

Importance Cost

Sturdy

base and mounting

to withstan

d vibrations

Able to be moved to different locations in

the shop

Overall

footprint

Save and recall test data to a wide

ly used form

at

Stand-

alone

data acquisitio

n and control

unit

Create

graphs

usable for testing

and tuning

dampers

Replay

test data back

in real time

Measure damper

forces

Measure damper

shaft position

Measure damper temperature during

test

Variable

stroke

range

Min/Max

eye to eye

distance

Reproduc

e frequencies

seen on

track

Measure fluid temperature

if possible

Cost less than $4,000.00 9     Sturdy base and mounting to withstand vibrations 9     Able to be moved to different locations in the shop 6      

Maximum foot print of 4' x 4' 6     Save and recall test data to a widely used format 9    

Stand-alone data acquisition and control unit 6     Create graphs usable for testing and tuning dampers 3    

Replay test data back in real time 3     Measure damper forces 9    

Measure damper shaft position 9     Measure damper temperature during test 9    

Variable stroke range 9     Ability to accommodate different sizes of dampers 6      

Reproduce frequencies seen on track 6     Measure fluid temperature if possible 3    

Unit of Measure $$ in BI in BI BI BI BI lb in ˚F in in Hz ˚F

Ideal Value <4000

<.005 48' x

48' >1500

.25 - 7 <250 .25 -

7 9 - 31 >100 <250

House of Quality

• Conclusions: Develop a dyno with Roehrig Capabilities, ½ price of the Intercomp.

• Other option is to use the Instron

Benchmark Existing Systems

Project Timeline

Questions?