ECE Department SDP07

Team Members:Chad BaldiJulian SalaiAllan MainaLinwood Williams

Team Advisor: Professor Omid Oliaei

FanSafe

2ECE Department SDP07

Origin of Idea

SawStop® technology• Capacitive based touch sensor

SawSafe • Chainsaw based proximity sensor

FanSafe• Industrial fans

3ECE Department SDP07

Concept

Human proximity detector• Electric field sensing

Stop the motor• Safety precaution

4ECE Department SDP07

Kirchhoff’s Voltage Law

5ECE Department SDP07

Marketability

Protective grill not needed• Easily cleanable

• Low accumulation of allergens and dust• Visual aesthetics

Industrial applications• Maximize air flow• Safety

6ECE Department SDP07

General Layout

Electrode Sensors

Sensor Circuit

Multi-Channel Slip Ring

Motor Stop Control Board

7ECE Department SDP07

MDR Specifications

Acquire fan Plans for sensor placement Analog sensing Interference Options in signal processing Data transfer solution

8ECE Department SDP07

MDR Specifications

Fan selection• Fan blade material• Size • Cost

9ECE Department SDP07

MDR Specifications

Sensor placement• Electrode / Shield material• Insulator material • Location on fan blade• Mount configuration• Coaxial connector type

10ECE Department SDP07

Fan Blade Sensors / Coax Components

11ECE Department SDP07

MDR Specifications

Analog Sensing• IC settings & properties• Use of Shield• Sensor specifications

12ECE Department SDP07

Sensor Circuit

Fan Blade Sensors

13ECE Department SDP07

Sensor Video

14ECE Department SDP07

MDR Specifications

Interference & Noise• Noise created in optimization of distance. (P-P 20mV)• No noise from AC Motor

15ECE Department SDP07

MDR Specifications

Signal processing concepts• Serial ADC• PIC processor• Noise averaging• Slope algorithm

16ECE Department SDP07

MDR Specifications

Data Transfer• Multiple port slip ring

• Power input to circuit• Sensor digital output

17ECE Department SDP07

Next Step

Acquire slip ring• Number of connections• Hallow ring• Possibly self made (cost/noise)• Needed for on-fan testing (priority)

SLIP RING

FANPCB

MOTOR PCB

VDD

AGND

DGND

DATA

18ECE Department SDP07

Next Step

Develop PCBs• Need for on-fan testing• Decide on A/D sampling rate• Resolve shielding issues

19ECE Department SDP07

Next Step

PIC processing code• With on-fan testing create processing algorithm

• Algorithm developed to detect proximity & kill noise

20ECE Department SDP07

Next Step

Motor stop relay• Develop process to stop motor • Timing may be critical • Possible mechanical brake technique

21ECE Department SDP07

FanSafe

Thank You.