FSAE Instrumentation 1/27/09 Ryan Gunn John Lee Dan Van Winkle Ali Yilmaz

Formula SAE Intercollegiate competition New car every year Cars designed for non-professional auto cross racer Over 120 international teams

FSAE Competition Scoring

Data Acquisition System Tuning is important Driver feedback Quantitative baseline Support design decision Driver evaluation

Operational Concept Real time data capture Post Processing Real time data transmission* Simultaneous data capture and transmission* Data analysis and reduction New/additional power sources* *Goals

Flow of Data in Hardware

Sensor Selection Shock Position Sensor Accelerometer Wheel Speed Sensor Oil Pressure Sensor Steering Position Sensor

Sensor Selection

DAQ Requirements

DAQS Options MoTec AIM Sports National Instruments cRIO

Motec Pros: Ease of installation User Friendly GUI Cons: High cost ($4000-$6000 for data logging unit) Limited to Motec sensors Locked software

AIM Sports Pros: Cheaper than Motec More, cheaper sensors available than Motec Cons: Price (~$2000) Locked software

NI cRIO Pros: No cost for DACS or sensors Changeable LabVIEW code Modular  Customizable Cons: Programming

Notes All options provided: Weight requirement Free tech support Free software

Decision NI cRIO is best choice for this application Cost is a critical factor Performance/accessibility factors can be worked on

Wireless Transmission Daniel Alford, “Light Weight, Low Cost, Automotive Data Acquisition and Telemetry System" (MS thesis, University of Cincinnati, 2005) “The testing performed shows that the wireless networking technology does not adversely affect the data being transferred” Standard antenna not well suited (range) Line of sight issues are the major problem

Decision Wireless data transmission will not initially be pursued Data logging issues Dependability Time constraints

Power Consumption cRIO-20W Accelerometer 180 μA mW Oil Pressure - 40mW Brake Pressure – 25mW Rotary Potentiometer – 0.7mW Proximity Sensor – 200mW Total ~300mW ~1.8 Amperes

Comparing Batteries Current Battery ODYSS PC310 Drycell 2.87 AH/kg 8 AH Possible Alternatives Li Ion 11.4 AH/kg Stringent charging requirements

Accomplished Tasks Installed software tools Established connection with the cRIO Updated software on cRIO Tested real-time monitoring Tested data logging

Real-time Monitoring Significant lag Requires constant connection to car (Requires wireless) Useful for testing sensors and data acquisition code Cannot log data simultaneously (Memory issues) A nice to have

Testing Real-time Monitoring

Data Logging Currently must be connected to computer Switch to turn on and off Boot file More complex process than real-time monitoring Allows for future analyzing of data

Testing Data Logging

Instructions Created List of all modules necessary to run software How to connect to the cRIO