Transcript Diapositiva 1

ANTS
Anesthesiology Neuromuscular
Monitoring System
#25
Group Information
Greg Angelotti (EE)
Otto Cruz (CpE)
Kristin “Zaza” Soriano (CpE/EE)
Sponsor: Dr. Thomas Looke
(Anesthesiologist/EE)
Current Methodology
• Administer Neuromuscular Blocking
Agents (NMBA)
– Blocks Acetylcholine (ACh)
• Trivial neuromuscular stimulating
• Subjective muscle response monitoring
(if any at all)
• Pen and paper record keeping
Current Methodology
*Courtesy of nursingcrib.com
Current Methodology
Stimulate
Monitor
Laments
Ulnar Nerve
Adductor Pollicis
Thumb
Posterior Tibial Nerve
Flexor Hallucis Brevis
Foot
Facial Nerve
Corrugator Supercilli
Eyebrow*
Facial Nerve
Orbicularis Occuli
Eyelid*
* Research shows not as reliable as the first two sites
Objectives
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To safely stimulate targeted sites
To effectively obtain patient signals
To accurately record patient feedback
To create a more organized environment
Requirements
• Must consist of safe modular subsystems
• Must obtain objective quantitative
muscular responses
• Must produce individual patient feedback
and logging
• Must reduce operating room clutter
Overall Block Diagram
Specifications
Shocking Device
Battery
3.7 Volt 2200 mAh Lithium Ion
Polymer
Up Time
6 Hours
Idle Time
3 Days
Input Voltage
3.7 Volts
Output Current
Variable 0 to 70 mA
Output Pulse
Square Wave Pulse 200us Duration
Train of Four
Single Set of 4 Pulses Per 2 Seconds
Tetanus
100 Hz (100 Pulses Per Second)
Twitch
1 Pulse Per Second
Dimensions
30 x 40 x 10 mm
Shocking Device
MCU & Bluetooth
Part
CC2540
BLE112
Manufacturer
Texas Instruments
Bluegiga
Dimensions
6.5 x 6.5 x 1 mm
MCU
8051
8051
Memory
128/256 Kb
128/256 Kb
Transceiver
Bluetooth 4.0
Bluetooth 4.0
Receiver
19.6 mA
19.6 mA
Transmitter
24.0 mA
27.0 mA
Power Consumption
2 to 3.6 volts
2 to 3.6 volts
Cost (Dev. Kit)
$289.75
$350.00
Shocking Device
Shocking Device
Current Control
• PWM to produce the 200us square wave
form.
• 10 Bit Serial SPI Dual Output DAC to
control current output.
• 2^10 taps (1024) with a 10 bit DAC
• Issues deciding between Digital
Potentiometer (voltage) and DAC (voltage
& current).
Current Op amp
• Current input varies between 0 to 150 uA.
• Current output 0 to 750 mA.
• Availability and price is the reason for this
part.
DC to DC Converter
• Optional part
• Input 3.1 to 75 volts
• Frequency Synchronization
Shocking Device
Negative Feedback
• DC Converter to ADC port on MCU
• Digital Integral controller to regulate the
stimulation current.
• Using the formula above will allow us to
control the stimulators output.
Shocking Device
Power Supply
• Voltage buck/boost regulator dual output
3.7 volts supplies processor & 5 volts
supplies DAC
• Boost Voltage regulator supplies op amp
at 8 volts
• The power supply is a 3.7 volt 2200 mAh
lithium ion polymer.
Overall Block Diagram
Specifications
Sensor Device
Dimensions
30 x 40 x 10 mm
Battery
5V
Up Time
6 Hours
Idle Time
3 Days
Data Transmission
Bluetooth 4.0
Wireless Range
<50 meters
Data Resolution
12 bit
Action Potential Detection
0 - 10 mV
Pressure Detection
0 - 10 lbs
Flex Sensor Angle
0 - 90 degrees
Sensor Device
Surface EMG
• Pick targeted sites
• Prepare the site
• Place Ag/Cl reference electrodes
• Ring Electrodes [preferred]
• Disc Electrodes [<10 mm]
• Ready to read patient action potentials
• 0-6 mV [Typical]
sEMG Preconditioning
Sensor Device
Tactile Pressure Sensor
Sensor
FSR 400
A301
Manufacturer
Sparkfun Electronics
Tekscan
Sensing Area
0.3”
0.375”
Force Range
0-10 lbs
0-25 lbs
Response Time
1-2 usec
<5 usec
Price
5.95 USD
16.25 USD
Image
Pressure Sensor Conditioning
• Standard Resistance
from sensor (FSR):
Inverting Amplifier
– Appr. 1 MOhm
• VREF should be
negative
– Appr. -5 Volts
• The smaller RG is the
more sensitive the
sensor becomes
Vout = (Vref)*(RG/Sensor)
Sensor Device
Flexible Potentiometer Sensor
Sensor
FS7548
SoftSpot
Manufacturer
Spectra Symbol
Spectra Symbol
Length
114 mm
100 mm
Thickness
.48 mm
.51 mm
Resistance Range
1 KOhm – 100 KOhm
1 KOhm – 10 KOhm
Price
14.95 USD
12.95 USD
Image
Bend Sensor Conditioning
• Standard Resistance
from sensor (FSR):
Inverting Amplifier
– Appr. 10 KOhm
• VREF should be
negative
– Appr. -5 Volts
• The more the sensor
bends the more the
greater the impedance
Vout = (Vref)*(RG/Sensor)
Sensor Device
Power Distribution
Overall Block Diagram
Specifications
Tablet Device
Dimensions
10” x 6 ¾” x 2”
Battery
4000 mAh, 5V
Up Time
4 Hours
Idle Time
8 Hours
Data Transmission
Bluetooth 4.0
Wireless Range
<50 meters
Screen Resolution
1024 x 600 pixels
Main Device
Touchscreen
Parameter
Specification
Diagonal Size
10.1”
Aspect Ratio
16:9
Resolution
4096 x 4096
Accuracy
±1.5 %
Transmissivity
90 %
Active Current
6 mA
Sleep Current
94 µA
Digital Power Supply
3.3 VDD
Touchscreen Controller
Custom I2C
Voltage-level Shifter
VIO
Pandaboard ES J6
Expansion Header
Main Device
TFT-LCD
Parameter
Specification
Diagonal Size
10.1”
Frame Rate
60 Hz
Resolution
1024 x 600 pixels
Maximum Power Consumption
2.6 W
Maximum Backlight Power Consumption
1.5 W
Thickness
0.5 mm
Digital Power Supply
3.3 VDD
IDD Current
240 mA
LCD Controller
LED Backlight
Control I/O
30-pin LVDS
Connection
Pandaboard ES
J3/J4
LCD I/O
Main Device
Pandboard ES
Features
Dual Core ARM Cortex A9 (1.2 GHz)
Graphics support (ex: OpenGL)
LCD expansion header
1 GB low power DDR2 RAM
SD card slot
General I2C expansion headers
802.11 b/g/n (WiFi)
Bluetooth 4.0
Awesome support community!
Pandaboard ES
Main Device
Tablet Power
• 6 volts 10000 mAh
• 23 x 99 x 71 mm
• $15-17
Tablet Software
• Ubuntu
• C++
• qT
Monitoring Screen
Bill of Materials (Tablet)
Item
Cost
10.1” TouchScreen
Free
10.1” TFT-LCD Display
$41.89
LVDS Cable
$9.88
LCD Controller Expansion
$57.18
Pandaboard ES
$180.48
Power adapter (dev)
$16.99
2.45mm pitch male pin headers
$6.46
USB to RS-232 adapter (dev)
$7.00
HDMI to DVI cable (dev)
$4.56
8Gb SD card
Free
Bill of Materials (Sensors)
Item
Cost
sEMG Electrodes
FREE
Pressure Sensor
$5.95
Bend Sensor
$12.95
Rotary Potentiometer
$1.75
Low Noise Op Amp x 3
$2.32
Differential Amp
$10.25
CC2450 Developers Kit (2 Modules)
$289.75
PCB Cost (Expected)
$70.00
Misc (Resistors,Capacitors,Diodes,etc)
Free
Bill of Materials (Total)
Device
Total Cost
Main Device (Tablet)
$324.44
Sensor Device
$392.97
Shocking Device
$70
Running Total
$787.41
Progress
Coming Soon?
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Finish prototyping
Finalize sensor PCB schematic for printing
Program microcontrollers
Sync Bluetooth devices
Integrate tablet parts
Software development
…Profit
Questions?