formula sae performance enhancement vu fsae instrumentation team – 12/13/2007

Formula SAE Performance Enhancement

VU FSAE Instrumentation Team – 12/13/2007

Collegiate design competition Small formula-style racing cars 1 year project time span

12/7/2007 Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation 2

610 cc max engine displacement 20 mm air intake Independent 4 wheel suspension Structural safety req’mts


120 International teams 10 international competitions sponsored by

Society of Automotive Engineers 1000 total points

Static events Dynamic events


FSAE Design Team System validates engineering design decisions

FSAE Competition Team System improves driver training/driver performance System improves vehicle performance

Data Analysis Team Data is easily accessible, interface is easy to use

FSAE Cost Team Impact on cost report

Senior Design Team Wants a system which is modular, easy to develop and

implement


Currently, performance tuning requirements developed from driver feedback

No quantitative performance measurements


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


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


Performance must be high enough that quantitative measurements can be made

Reliability another performance issue Low cost enough to fit in FSAE team budget


External Systems Car components

▪ Suspension▪ Engine▪ Chassis

FSAE Competition▪ Endurance Event▪ Acceleration▪ Skidpad

Environmental Systems Vehicle Context

▪ EMI▪ Vibration▪ Heat

Weather▪ Rain▪ Hot Ambient Temp▪ Cold Ambient Temp


Based on contextual requirements Divided into four categories

Measurables Environmental Operational Interface


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.

System expandability Optionals = future project potential


REQUIRED OPTIONAL EXTRANEOUS

Shock Position & Velocity Tire Temperature 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


Required


Measured Resolution Sampling Dynamic Range

Signal On track (in) Hz (S/sec)

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 0-150 psi

Throttle Position 6 200 100 degree range

Steering Position 3 400 540 degree range

Brake Pressure 6 200 0-12500 psi

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

Weight - <20 lbs Size – 10”x12”x5” max envelope


Triggering Data Pre-filter Data processing Storage Capacity, 25MB (see next slide) Data Transfer

Download all data < 1min, 0.4MB/sec SAE stand alone compliance

Monitors and records only Passive, no direct feedback to driver Not needed for vehicle operation


Storage capacity derivation from measureable requirements


Measured Sampling Minimum Bit Bit rate Data SizeSignal Hz (S/ sec) Channels Resolution bytes/ sec MB (60min)Shock Position/Velocity 400 4 16 3200 10.99Lat./Long. Accel 200 2 16 800 2.75Wheel Speed 200 2 16 800 2.75Engine RPM 200 1 16 400 1.37Oil Pressure 20 1 16 40 0.14Throttle Position 200 1 16 400 1.37Steering Position 400 1 16 800 2.75Brake Pressure 200 2 16 800 2.75

Data Capacity: 24.87

Graphs Gauge levels Scatter plots Channel history

FFT output Channel reports Section times Real-time playback


The system must have various options to represent:

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 stock28 analog inputs and up to 4 digital inputsMaximum logging rate 20 Kbytes per second32 Bit microprocessorData analysis software USB interface


Advantages 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 24

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


Advantages 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 AIM12/7/2007 Vanderbilt University FSAE Instrumentation Project - Fall Semester Presentation 26

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

Integrates with NI’s LabVIEW software USB & Ethernet interface


Discussion of Options – cRIO/custom

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 Disadvantages

LabVIEW will require learning a new programming environment

Wiring harness will have to be fabricated separately

Requirements ~3,500 samples/sec 14 channels 25MB storage 0.4MB/s transfer rate 20 – 105 F <20lbs 10”x12”x5” max

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



cRIO Block Diagram

Operational Definition

On-board memory

GUI Data Reduction

GUI Interface

RS232

CAT5


Measurement Sensor BrandPart Number Cost

Shock Position/RateLinear Potentiometer

Latitudinal and Longitudinal Acceleration Accelerometer Crossbow

GP Series tri axis $315

Wheel Speed Proximity Sensor OmegaPRX-102-8n $85

Engine RPM Direct**Data can be taken directly from engine - Honda CBR600F4

Oil PressurePressure Transducer Omega

PX32B1-250GV

Already own

Throttle PositionRotary or String Pot

Steering PositionRotary or String Pot

Brake PressurePressure Transducer Omega PX305-3KGI $285

Custom hardware alterations

Custom Input/Outputs Custom control

hardware Easy-to-use graphical

development Built-in interface

functions integrated into cRIO


Measurables Bench test sensors – verify output accuracy

Operational Visual Inspection Operational successfulness

Interface Visual Inspection


V&V Methodology

formula sae performance enhancement vu fsae instrumentation team – 12/13/2007

Documents

fsae racecarcan

semester presentationcurrently

semester presentationneed

quantitative measurements

usefsae cost teamimpact

air intakeindependent

various weather conditions

onboard memorysystem