CRITICAL DESIGN REVIEW - SensorBallSponsors: Anthony Vaughan, Evan Sawyer, Matt Poole, Peggy Liska Members: Maryam Abdul-Wahid, Tamara Alani, Angel Lopez, Brian Ngo, Ryan Stelzer
December 3, 2015
AGENDA• Introduction - Overview of the project and requirements• Changes since PDR• Overview of Design - System Block Diagram • Subsystem Designs and Analysis
– Structure – Electronics – Software
• Test procedures• Risk Analysis• EVMS Summary• Cost Analysis/BoM• Summary and Next Steps
INTRODUCTION•Showcase TI products at a tradeshow
•Highlight 4 product lines–SAR ADC–Delta-Sigma ADC–DAC–Operational Amplifiers
•Sensors–Accelerometer–Temperature–Light–Heart Rate
CHANGES SINCE PDRNon-Functional Requirement
The ball shall have 20 RGB LEDs, each string emitting at least 3 lumens, driven by TI DACs and Amplifiers.
Verification MethodVerify by inspection of datasheet
TOP LEVEL DESIGN
SUBSYSTEM DESIGN & ANALYSIS
STRUCTURE
Ryan Stelzer
STRUCTURE
Electronics Stack
Leg
Ring
Ball/Sphere
Nucleus
Battery
~2.2 pounds total
STRUCTURE - BALL
• PETG plastic hemispheres, 12” D– Purchase sphere
• HDPE plastic ring, ¼“ thick, ~.5 lb– Custom order
STRUCTURE - NUCLEUS
• Acrylic, 3” x 3.5” x 3.5”, ~1 lb • Insets for carbon fiber legs• 10-32 ¾” screws• AME Machine shop
STRUCTURE - LOCATION OF ELECTRONICS
• Battery attached underneath nucleus• Temperature and heart rate sensors at end of legs• LED strips on face of legs• LED/sensor wiring runs through legs
ELECTRONICS
Tamara Alani & Maryam Abdul-Wahid
ELECTRONICS BLOCK DIAGRAM
ELECTRONICS BLOCK DIAGRAM
MCUSCHEMATIC
1
ELECTRONICS BLOCK DIAGRAM
TEMP.SCHEMATIC
2
ELECTRONICS BLOCK DIAGRAM
ACCEL.SCHEMATIC
3
ELECTRONICS BLOCK DIAGRAM
VIBRATIONSCHEMATIC
4
ELECTRONICS BLOCK DIAGRAM
HEART RATESCHEMATIC
5
ELECTRONICS BLOCK DIAGRAM
LIGHT SENSORSCHEMATIC
6
ELECTRONICS BLOCK DIAGRAM
BLE/LEDSCHEMATIC
7
BATTERYPOWER TREE
130mA
500mA
BATTERYSCHEMATIC
8
ELECTRONIC STACK - BOTTOM
Power
MCU
BLE HM-11
ELECTRONIC STACK - TOPAccelerometer placed here
Light Sensor
Op Amp for Heart Rate
ADC for Temperature Sensor
Vibration motor placed here
EXTERNAL PCBs
Heart Rate Monitor PCB Temperature Sensor PCB
RTD Placed Here
SOFTWARE
Angel Lopez
SYSTEM BLOCK DIAGRAM - MCU● BLE’s Baud Rate is 9600.● Sensor Reading is limited by BLE transfer speed.● Read one sensor ata time with SPI
MCU STATE DIAGRAM
GRAPHICAL USER INTERFACE - LabView
BOUNCE N’ BEATACCELEROMETER & HEART RATE MONITOR
1.Measure user’s resting heart rate (in BPM)2.Add 20 BPM to resting heart rate for target heart rate3.Challenge user to reach target heart rate (or higher) by only moving
in the X-direction (Y- and Z- direction will have thresholds)
• Visual feedback:– YELLOW: game is in progress, no violations– RED: user has crossed the Y- and Z- thresholds (activate vibration
motor)– GREEN: user WINS!
ACCELEROMETER & HR DEMO• Top shows Target Heart Rate• Graph shows Z-axis acceleration data• The two sliders show whether a person
is under the desired threshold X
Z
CAN I GET A WATT WATT?LIGHT SENSOR
• LED brightness varies inversely with the irradiance measurement
• When light irradiance is high, LEDs will be DIMMED• When light irradiance is low, LEDs will be BRIGHTENED
LIGHT DEMO• Text box will display irradiance.• User may select what color the
LEDs on the ball will display through the GUI using the dial.
SENSORBALL SENSESTEMPERATURE SENSOR
• Measure user’s body temperature• Display ‘fortune’ on GUI
You’re sad, go eat a waffle
Error 404: Fortune not found
39 days, 18 hours, 2 minutes, and 14 seconds...
You will adopt 13 cats tomorrow
You’re HOT
TEMPERATURE DEMO• Mood text box will display user’s
mood based on user’s temperature
• Temperature textbox will display user’s body temperature
• LED color will correspond to mood
TEST PROCEDURES
Brian Ngo
TESTS• The ball must be able to withstand a 6 foot drop - STRUCTURAL INTEGRITY• The ball must weigh less than 10lbs*• Two games/demos*• Operating battery life of 8 hours*• The ball must contain multicolored lights*• System must restore full power within 12 hours - RESTORATION• PC and system must communicate bi-directionally*• The GUI will receive sensor data within 2 seconds*• Temperature of the ball (outer structure) must not exceed 100°C while in use*• GUI must be compatible with Windows 7 and 10 - COMPATIBILITY
(*) - Trivial Tests
TEST: The ball must be able to withstand a 6 foot drop (preferred).TEST PROCEDURE:
1. Perform the following test on concrete and carpet flooring.
2. Use a measuring tool (ruler, measuring tape, or a pre-measured marker) to measure 6ft. +/- .5ft. from the ground upwards. Record.
3. Drop the ball from the measured height using hands or table top.
4. Inspect the ball for any damages. Record data.
5. Test that the system functions properly.
6. Repeat Steps 3-5 two more times.
STRUCTURAL INTEGRITY - TEST PROCEDURE
STRUCTURAL INTEGRITY - DATASHEET❏ Pass
Measured height ______ feet.Record data in table below:
Rate the damages as one of four options: none, minor, moderate or severe.
State if the system is functional: yes - functioning, no - not functioning.
Make a note of each test.Test 1 Test 2 Test 3
Concrete Carpet Concrete Carpet Concrete Carpet
Damages
Functional
Notes
❏ Fail, why ________________________________
RESTORATION - TEST PROCEDURE
TEST: The ball must restore full power within 12 hoursTEST PROCEDURE:1.Disassemble ball2.Charge battery pack to full power3.Record time to charge4.Reassemble ball5.Power ball6.Display data from all 4 sensors on GUI7.Record this data onto datasheet
RESTORATION - DATASHEET❏ Pass
Check off whether each sensor displays data after restoration:
Pass Fail
AccelerometerTemperatureLight SensorHeart Rate
Time to restore power: __________ Hrs
❏ Fail, why ________________________________
❏ ❏ ❏
❏ ❏ ❏
COMPATIBILITY - TEST PROCEDURE
TEST: GUI must be compatible with Windows 7 and 10TEST PROCEDURE:1.Power ball and PC2.Load GUI on Windows 73.Switch game modes using the GUI4.Record result on datasheet5.Change LED color using the GUI6.Record result on datasheet7.Repeat steps 1 - 6 on Windows 10
COMPATIBILITY - DATASHEET❏ Pass ❏ Fail, why
________________________________
Can the GUI switch between games and demos?
Yes/No
Does the GUI allow you to change the color of the LEDs in the ball?
Yes/No
Can the GUI switch between games and demos?
Yes/No
Does the GUI allow you to change the color of the LEDs in the ball?
Yes/No
WINDOWS 7 WINDOWS 10
RISKS/BOM/EVMSBrian & Maryam
RISK MATRIX1. Unable to
schedule meetings
2. Power supply3. Structure design 4. Labor resource 5. Receiving
materials and electronics
6. Software bugs
60
Likelihood Consequences
Insignificant (easily handled)
Minor (some disruption)
Moderate (significant time/resources required)
Major (project severely damaged)
Catastrophic (project down the tubes)
Almost certain (>90%)
High High Extreme Extreme Extreme
Likely (50%-90%)
Moderate6
High High Extreme Extreme
Moderate (10%-50%)
Low Moderate2
High3
Extreme Extreme
Unlikely (3%-10%)
Low Low Moderate5
High4
Extreme
Rare (<3%) Low Low Moderate1
High High
BOM
DRAWING STATUSDRAWING STATUS
STRUCTURE● (1) NUCLEUS SIDE - SHORT● (2) NUCLEUS SIDE - LONG● (3) NUCLEUS BOTTOM● (4) NUCLEUS SUB-ASSEMBLY● (5) LEG MODIFICATION● (6) SPHERE SUB-ASSEMBLY● (7) ASSEMBLY
DONE
SCHEMATICS● MCU● TEMPERATURE SENSOR● LIGHT SENSOR● ACCELEROMETER● HEART RATE MONITOR● BLE● LED & DRIVER● POWER● VIBRATION MOTOR
DONE
PCB● ELECTRONIC STACK - BOTTOM● ELECTRONIC STACK - TOP● HEART RATE● TEMPERATURE
DONE
EVMS PROJECT PLAN SUMMARY
SUMMARY & NEXT STEPS• Nucleus structure in plastic ball• Temperature, accelerometer, light, and heart rate sensors• LabView GUI
Next Steps• Place remaining orders• Start building and testing
QUESTIONS?
APPENDIX
CENTER OF MASS ANALYSIS
MATERIAL FAILURE ANALYSISLowest FoS for different failure modes
BLUETOOTH ATTENUATION ANALYSIS
• Calculate the path loss due to free space and the PETG plastic. Compare the loss to the communication link margin between the transmitter and the receiver. Communication will occur if loss is less than the link margin.
• BLE HM-10 has four RF options. The larger the value, the better the signal and wider the range.
UML
BATTERYLIFETIME
