Formula SAE Performance Enhancement
VU FSAE Instrumentation Team – 12/13/2007
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Collegiate design competition
Small formula-style racing cars
1 year project time span
12/7/2007
Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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610 cc max engine displacement
20 mm air intake
Independent 4 wheel suspension
Structural safety req’mts
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Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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120 International teams
10 international competitions sponsored by
Society of Automotive Engineers
1000 total points
 Static events
 Dynamic events
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Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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12/7/2007
Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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FSAE Design Team
 System validates engineering design decisions
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FSAE Competition Team
 System improves driver training/driver performance
 System improves vehicle performance
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Data Analysis Team
 Data is easily accessible, interface is easy to use
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FSAE Cost Team
 Impact on cost report
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Senior Design Team
 Wants a system which is modular, easy to develop and
implement
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Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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Currently, performance tuning requirements
developed from driver feedback
No quantitative performance measurements
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Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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Need a system which can capture and store
multiple data channels
Capable of operating on a FSAE racecar
Can withstand exposure to various weather
conditions including hot, cold and rain
12/7/2007
Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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Various sensors networked to an analog to digital
converter
Digital converter will process data and store it in
onboard memory
System will download data to laptop
GUI on laptop will display and analyze data
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Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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Performance must be high enough that
quantitative measurements can be made
Reliability another performance issue
Low cost enough to fit in FSAE team budget
12/7/2007
Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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External Systems
 Car components
▪ Suspension
▪ Engine
▪ Chassis
 FSAE Competition
▪ Endurance Event
▪ Acceleration
▪ Skidpad
12/7/2007
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Environmental Systems
 Vehicle Context
▪ EMI
▪ Vibration
▪ Heat
 Weather
▪ Rain
▪ Hot Ambient Temp
▪ Cold Ambient Temp
Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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Based on contextual requirements
Divided into four categories
 Measurables
 Environmental
 Operational
 Interface
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Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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Three categories
 Required
▪ These contribute the most to analyzing and validating
vehicle and driver performance.
 Optional
▪ Not focused on driver performance. Future project
potential?
 Extraneous
▪ Do not contribute to understanding driver or vehicle
performance, but could be measured.
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Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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REQUIRED
Shock Position & Velocity
OPTIONAL
Tire Temperature
EXTRANEOUS
Fuel Level
Lateral & Longitudinal Accel.
Ambient Temperature
Fuel Consumption Rate
Wheel Speed
Water Temperature
Oil Level
Engine RPM
Exhaust Temperature
Coolant Level
Oil Pressure
Oil Temperature
Tire Pressure
Throttle Position
Wheel Load
Ride Height
Steering Position
Chassis Slip Angle
Brake Pressure
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Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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Required
Measured
Resolution
Sampling
Signal
On track (in)
Hz (S/sec)
Dynamic Range
Shock Position/Velocity
3
400
2.5";Vmax = 400mm/sec
Lat./Long. Accel
6
200
+/- 4g
Wheel Speed
6
200
60 rpm max
Engine RPM
6
200
0-13,000 rpm
Oil Pressure
60
20
Throttle Position
6
200
100 degree range
Steering Position
3
400
540 degree range
Brake Pressure
6
200
0-12500 psi
12/7/2007
0-150 psi
Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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System must withstand normal operating
conditions on FSAE racecar
Electro-magnetic Interference (EMI)
Water Exposure
Vibration
Temperature
 Ambient (20-105 deg F)
 Local heat sources
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Weight - <20 lbs
Size – 10”x12”x5” max envelope
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Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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Triggering
Data Pre-filter
Data processing
Storage Capacity, 25MB (see next slide)
Data Transfer
 Download all data < 1min, 0.4MB/sec
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SAE stand alone compliance
 Monitors and records only
 Passive, no direct feedback to driver
 Not needed for vehicle operation
12/7/2007
Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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Storage capacity derivation from measureable
requirements
Measured
Sampling
Minimum
Bit
Bit rate
Data Size
Signal
Hz (S/sec) Channels
Resolution bytes/sec
MB (60min)
Shock Position/Velocity
400
4
16
3200
10.99
Lat./Long. Accel
200
2
16
800
2.75
Wheel Speed
200
2
16
800
2.75
Engine RPM
200
1
16
400
1.37
Oil Pressure
20
1
16
40
0.14
Throttle Position
200
1
16
400
1.37
Steering Position
400
1
16
800
2.75
Brake Pressure
200
2
16
800
2.75
Data Capacity: 24.87
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Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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The system must have various options to
represent:
 Graphs
 FFT output
 Gauge levels
 Channel reports
 Scatter plots
 Section times
 Channel history
 Real-time playback
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Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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The M SD Dash / Logger is a combined LCD
Dash and High Performance Data Logger
 Cable bracket, Harness probable need to be
through MoTec to fit system
 16 MB max, 8 MB stock
 28 analog inputs and up to 4 digital inputs
 Maximum logging rate 20 Kbytes per second
 32 Bit microprocessor
 Data analysis software
 USB interface
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Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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Advantages
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Turn-key system is easy to setup and use
Great software user interface
High performance and proven product
Can receive support from MoTec for
troubleshooting and equipment failure
Disadvantages
 Cost – $4900, not including sensors
 Cannot add sensors to data logger or modify
interface if not predefined by MoTec
12/7/2007
Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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DaVid is a video and data logging system
AIM does not make ECU, must purchase
independently (third party)
8 MB stock
5 analog inputs
Maximum logging rate 50 Hz (Slow)
Data analysis software (Not as good as
MoTec)
USB interface
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Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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Advantages
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Turn-key system is easy to setup and use
Average Software user interface
High performance and proven product
Can receive support from AIM for troubleshooting and
equipment failure
Disadvantages
 Cost – At least $2500, not including sensors
 Few inputs, few predetermined sensor options and
weak memory
 Cannot add sensors to data logger or modify interface
if not predefined by AIM
12/7/2007
Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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The National Instruments CompactRIO is a
modular data input/logger/analysis system
64 MB DRAM available
Using the NI 9205 & 9215 modules:
 16 bit resolution
 36 measurable channels
 Maximum logging rate 650k samples per second
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Integrates with NI’s LabVIEW software
USB & Ethernet interface
12/7/2007
Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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Advantages
 Sensor choice is very open & not limited by NI
 Extensive NI & LabVIEW support available
 Cost – free for hardware & software (already provided
by NI)
 Meets or exceeds all quantitative systems reqs.
 Modular system allows interchangeability and
expandability as desired
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Disadvantages
 LabVIEW will require learning a new programming
environment
 Wiring harness will have to be fabricated separately
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Requirements
~3,500 samples/sec
14 channels
25MB storage
0.4MB/s transfer rate
20 – 105 F
<20lbs
10”x12”x5” max
12/7/2007
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Capabilities
650,000 samples/sec
36 channels
64MB onboard DRAM
USB: 1.5MB/s
-40 – 70 C
Change to as config. wt
7”x4.5”x3.5”
SAE Standalone
compliant
Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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cRIO Block Diagram
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Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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RS232
CAT5
GUI
Interface
GUI Data
Reduction
On-board
memory
12/7/2007
Brand
Part
Number
Accelerometer
Crossbow
GP Series
tri axis
$315
Wheel Speed
Proximity Sensor
Omega
PRX-1028n
$85
Engine RPM
Direct
**Data can be taken directly from
engine - Honda CBR600F4
Oil Pressure
Pressure
Transducer
Omega
PX32B1250GV
Throttle Position
Rotary or String
Pot
Steering Position
Rotary or String
Pot
Brake Pressure
Pressure
Transducer
Omega
PX305-3KGI
Measurement
Sensor
Shock Position/Rate
Linear
Potentiometer
Latitudinal and
Longitudinal
Acceleration
Cost
Already
own
$285
Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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12/7/2007
Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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12/7/2007
Custom hardware
alterations
Custom Input/Outputs
Custom control
hardware
Easy-to-use graphical
development
Built-in interface
functions integrated
into cRIO
Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation
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V&V Methodology
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Measurables
 Bench test sensors – verify output accuracy
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Operational
 Visual Inspection
 Operational successfulness
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Interface
 Visual Inspection
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