Helicopter Data Acquisition SystemHelicopter Data Acquisition System

ECE 4522 Senior Design IIECE 4522 Senior Design II

Team MembersTeam Members

David PaulDavid Paul

Aaron HillAaron Hill

Robert McInnisRobert McInnis

Jason SchemmelJason Schemmel

Dr. Rob KingDr. Rob King (Advisor)(Advisor)

Team ResponsibilitiesTeam Responsibilities Aaron Hill (Power)Aaron Hill (Power)

Power consumption, PCB layout, and documentation

David Paul (Controls)David Paul (Controls)

Control circuit design and synchronization

Jason Schemmel (Communications)Jason Schemmel (Communications)

Antenna simulation, transmitter/receiver research, PCB layout

Robert McInnis (Communications)Robert McInnis (Communications)

Signal conditioning, sampling, and data conversion

HelicopterHelicopter

Design ExplanationDesign Explanation

Hub

Blade

Pivot

Nonlinear stiffness spring

POT

Strain Gauge

Design ExplanationDesign Explanation

HUBHUB PIVOTPIVOT

Strain Gage

Design ExplanationDesign ExplanationPosition Position

TransducerTransducerPosition Position

TransducerTransducer Battery Battery Pack Pack

Power Power SourceSource

900 Mhz 900 Mhz TransmitterTransmitter900 Mhz 900 Mhz

TransmitterTransmitter

2:1 Mux2:1 Mux2:1 Mux2:1 Mux

10 bit A/D Converter10 bit A/D Converter10 bit A/D Converter10 bit A/D Converter

Wheatstone Wheatstone BridgeBridge

Wheatstone Wheatstone BridgeBridge

Amplifier Amplifier Signal Signal

ConditionerConditioner

Amplifier Amplifier Signal Signal

ConditionerConditioner

Strain GaugeStrain GaugeStrain GaugeStrain Gauge

KEYKEY

PowerPower

SignalSignal

EM SignalEM Signal

BASIC Stamp BASIC Stamp MicrocontrollerMicrocontrollerBASIC Stamp BASIC Stamp

MicrocontrollerMicrocontroller

Design ExplanationDesign Explanation

Helicopter Helicopter House House PowerPower

10 bit D/A 10 bit D/A ConverterConverter

10 bit D/A 10 bit D/A ConverterConverter

KEY

Power

Signal

EM Signal

Data Enable

900 MHz 900 MHz ReceiverReceiver

900 MHz 900 MHz ReceiverReceiver

LaptopLaptopLaptopLaptop

Internal Internal Sensor Sensor

PackagePackage

Internal Internal Sensor Sensor

PackagePackage

DAQ DAQ PCMCIAPCMCIADAQ DAQ

PCMCIAPCMCIA

BASIC Stamp BASIC Stamp MicrocontrollerMicrocontrollerBASIC Stamp BASIC Stamp

MicrocontrollerMicrocontroller

10 bit D/A 10 bit D/A ConverterConverter

10 bit D/A 10 bit D/A ConverterConverter

Status - CompleteStatus - Complete

• Transmission / reception

• Data conversion

• Acquisition instrumentation

• Power supplies

• Dual signal multiplexing

• BASIC Stamp programming/implementation

Status – IncompleteStatus – Incomplete

• PCB

• Software

• Strain Gauge Signal Conditioner

• Adequate noise filtration

Simulation ComparisonSimulation Comparison

Control SignalControl Signal

Channel 1

Channel 0Simulated Signal

5V

0V

5V

0V

Simulation ComparisonSimulation Comparison

Sampling RateSampling Rate

0 1 2 3 4 5 6 7 8 -100

-80

-60

-40

-20

0

20

40

60

80

100

Time (sec)

Bla

de L

ead

Ang

le (

deg)

Baseline Case w/ Duffing Spring Transmitted Signal

Input Signal (3Hz)

Simulated Input Signal

Problems SolutionsProblems Solutions

1. Encoder/Decoder was slowing our sampling rate

2. Transmission Scheme transmitting unwanted address bits @ 10 kbps (22 bits per packet) 300MHz

3. Error checking overkill

1. Implemented BASIC stamp for quick custom solution

2. Using 50 kbps @ 900 MHz scheme transmitting 2-10 bit packets

3. Parity checking performed by BASIC stamp

Problems SolutionsProblems Solutions

4. Multiplexor would not latch analog data for output

5. Overall system noise.

4. Used a dual D/A configuration with control logic tied to chip selects.

5. Each chip data sheet calls for different de-coupling capacitors, which will be utilized during PCB design stage.

PCB DesignPCB Design

Receiver Schematic

PCB DesignPCB Design

• Used Microsim PC-Boards (P-SPICE)

• Encountered Node Limit (Shareware)

• Single sided • Decided to use Express PCB

– Included CAD software– Double sided– Quick turnaround

Technical Challenges Technical Challenges RemainingRemaining

• Final PCB Layout with size consideration

• Noise filtration during testing

• Calibration of acquisition devices

(i.e. strain gage)

Placement of Transmitter Placement of Transmitter PackagePackage

• Size limitations of PCB board (6”x2.5”)

• Proposed position of final installation of Transmitter PCB board.

Placement of Transmitter Placement of Transmitter PackagePackage

• Packaging can be up to 2.5 inches tall

• Package will be secured to rotor tightly to prevent our hard work from slinging away

TimelineTimeline

January February March April MayPrototype

DAQ Software

Testing/ Tweaking

PCB Fabrication

Final Documen-tation

Preliminary Design Review

Final Design Review

Preliminary Hardware Review

Future ImprovementsFuture Improvements

Implement remote transmitting on/off switch

Battery reduction circuitry

Graphical User Interface (GUI)

Automated helicopter control system

Eliminate D/A conversion, allow Computer to do any needed operations to data

Helicopter Data Acquisition SystemHelicopter Data Acquisition System

ECE 4522 Senior Design IIECE 4522 Senior Design II

The End