1. Watermelon Ripeness Sensor
Melon Inc.
In Search of Perfect Melons.
Jason L. Firko
Allan Cohen
Matt Behr
Dave Bartoski

2. Watermelon Ripeness Sensor
Team #2 Members:
Jason Firko
Matt Behr
Allan Cohen
Dave Bartowski
Customer: Ed Kee Advisor: Dr. James Glancey
Mission: Develop a non-destructive method and apparatus for accurately determining the ripeness of watermelons.
Approach: Use customer wants to research and develop the most useful solution to the problem of determining watermelon ripeness. Develop a prototype and test it in an actual working enviroment.

3. Background Watermelon market is a large, worldwide market
Grown on 5 Continents
Grown in 90 countries
Annual production 50 Billion lbs./year
75% of the melons bought whole
Large domestic and international market
Problem with a long history University of Georgia Study
There are currently no accurate non-destructive testing methods available

4. Design Concept Review Introduction Concept Generation
Customers, Wants, Constraints, Benchmarking, Target values, Concept generation
Concept Selection
Evaluation against Metrics/Target Values, Concept Development, Working Model
Schedule
Actuals, Schedule, Budget

5. Customers & Wants

6. Customers Top Wants 1. Accuracy 2. Portability 3. Food Quality 4. Cost
5. Durable
6. Easy to Use
7. Fast
8. Versatility
9. Maintenance
10. Service Life

7. Constraints Maximum - $3000 Budget Abide by all FDA Regulations
Food Quality
Abide by all OSHA Regulations
Safety Standards

8. Metrics/Target Values
Provide a Means of Objective Measurement
Eliminate Ambiguity
Target Values
Derived From Customer Wants, Functional Benchmarking, Continued Customer Dialogue
Contact Regulatory Agencies
Listed With Related Wants (Ranked)

9. Metrics & Related Wants
Accuracy/Portability
% Correct Ripeness Readings (95%)
% Error in Sugar Content **
(False Neg./False Pos.) Readings (3)
Weight (51 lbs.)
Size (Dimensions) (3’ Sides)
# People - Transport/Operation (1)
Production Cost [$700]

10. Durability/Ease of Use/Speed
Metrics (Cont’d)
Durability/Ease of Use/Speed
Hours of Continuous Operation [12 hrs.)
Impact Resistance (3 ft. Drop)
Time to Train [1 hr.]
Number of Steps [5]
Level of Education Required [Grade 8)
Time/Cycle [10 sec]
Time per Shipment [2 hrs.]

11. Food Quality/ServiceLife/Versatility/Maintenance
Metrics (Con’t)
Food Quality/ServiceLife/Versatility/Maintenance
Size of Intrusion (1mm)
Bacteria Introduced *
Visual Quality Inspection Rating (1-10)
Estimated Years of Service (5 yrs.]
# of Uses (melon types, sizes, etc.) (4)
Cost/Cycle (parts, upkeep, etc) ($.001/cycle)

12. Initial Systems Benchmarking
Current Methods Of Watermelon Testing
Traditional - Thumping, stem color, skin color, other traditional methods
Destructive Testing - Sucrometer readings
Near Infrared Testing - Experimental technique of sensing sugar content
Acoustic Testing - University of Oklahoma

13. Systems Benchmarking Cont.
Related Procedures (Fruits and others)
Thumping/Resonance Tires, Fruits
Acoustic testing Acoustic Emission Testing
Ultrasonic testing Materials, Medical
Optoelectrics Apples
Intrusive testing Medical(Syringes)
Nuclear magnetic resonance Fruits, Medical
Electronic sniffing Strawberries

14. Concept Generation - Framework
Sensor is Critical Function/Element
Concept Generation Primarily Deals With This Element

15. Functional Benchmarking
Details of the Critical Element
Acoustic/Impact Tests-Sound signature and Resonance
Acoustic Sensors- microphones, AE sensors
Impact Devices- pendulums, hammers,spring loaded, etc.
Acoustic data acquisition devices
Testing of Rind Quality
Accelerometers and related tracking devices
Resistivity Testing
Available info. Of resistivity of biological materials
Probes, measuring devices, necessary equipment

16. Functional Benchmarking (Cont’d)
Ultrasonic testing
Use on biological materials
Available Machines
Sizing Devices
Oversized calipers
Scales
Sampling devices and methods
Syringes, automated sucrometers

17. Concept Generation SONIC TESTING - WHITE NOISE ACOUSTIC RESONANCE
INFARED
ENERGY IMPACT
STRAIN GAUGE
FLUID EXTRACTION
ACOUSTIC RESONANCE
ELECTRICAL PROPERTIES
ULTRASOUND
NUCLEAR MAGNETIC RESONANCE (NMR)
SONIC TESTING - SINGLE FREQUENCY

18. Concept Evaluation/Selection Process
Is this a viable solution?
Evaluate in terms of ranked metrics
Presentation - Time Constraints
Method - Comparison with metrics(related wants)
Strong in metrics
Weak in metrics
Notes on concept
SSD and Testing results lead to selection

19. Concept Evaluation Nuclear Magnetic Resonance
Out of Budget - $60,000 - $1,000,000
Sonic Testing- Single Frequency
Food Quality, Speed
Easy to Use, Accuracy, Maintenance, Cost
Difficult to Use- Need Proper Environment

20. Concepts Evaluation (Cont’d)
Sonic Testing- White Noise
Food Quality
Speed, Cost, Accuracy, Portability, Easy to Use
Need Controlled Conditions
Infrared
Accuracy, Speed, Food Quality
Expensive(Cost & Maintenance], Easy, Portability
High Power, Auxillary Equiptment Needed

21. Concept Evaluation (Cont’d)
Energy Impact
Quick, Easy, Food Quality, Portability, Durability
Accuracy
Related to External Properties, Not Internal
Strain Gauge
Portable, Food Quality
Easy to Use, Speed, Accuracy
Related to Rind Properties
Fluid Extraction With Syringe
Accuracy, Portability, Easy to Use
Food Quality, Maintenance
Intrusive

22. Ultrasound Testing - CCM Catch 22 Not a Viable Sensing Mechanism
High Frequency - Cannot Penetrate Rind
Low Frequency - Cannot Sense Density Changes
Other Problems - Air Pockets, Seeds
Food Quality, Service Life, Versatility
Accuracy, Portability, Cost, Speed
Not a Viable Sensing Mechanism

23. Electrical Properties
Resistance Testing
RC Modeling
Data Normalized For Physical Parameters & Sugar Content
Portability, Cost, Maintenance, Service Life
Accuracy, Food Quality, Speed
No Correlation Found - Not a Viable Sensing Mechanism

24. Electric Testing

25. Acoustic Resonance Testing
Based on Traditional Method
Acoustic Properties have been used to indicate ripeness
Accuracy, Portability, Food Quality, Cost, Easy, Fast
Maintenance

26. Concept Selection Acoustic Testing
Scored Highest in SSD - Received 8.9 / 10.0
Historical Basis - Benchmarking
Four main parts: Sensory, Data Acquisition, Data Analysis, Display/Interface
Focus on Sensory Portion of Design Development

27. Concept Selection - Metrics
Want/Metric Value
Accuracy >present
Portability lbs, 1 Person, 2’ sides
Cost $950
Speed <10sec
Food Quality 0 Bacteria, Non-Intrusive
# of Uses Local Varieties

28. Concept Selection - Testing
Performed Testing - 18 melons
All melons were in ripe range (8 - 12% sugar)
Determined Repeatability and Reliability
Impact Height, Turning, Repeated Testing

29. Concept Selection - Testing
Conclusions
Audible Signature Noticeable
No Negative Data
Need Further Testing - Variety
Grow green melons
Possible Correlations -
Secondary Spikes
Damping Characteristics

30. Working Model Two Component Working Model
(i) - Experimental Set up - Dr. Sun’s Lab
(ii) - Working Model

31. Planned Schedule

32. Actual Schedule

33. Future Critical Tasks Continue iterative concept evaluation
Develop further the data acquisition & analysis
Determine if we Can use a PCI or ISA card for data acquisition tasks
Order used laptop or microprocessor to perform our calculations
Determine software or computer code / learn
Obtain a shipment of melons of varying ripeness
Grow watermelons in greenhouse & Obtain shipment of melons
Perform further acoustic testing and refine correlation
Refine the thumping device through continued testing
Take a tour of the farm and working environment
Attend the watermelon growers convention

34. Estimated Budget Total cost for Initial Concept Prototype $ 872.99
Microphone $
Microprocessor/Laptop $
Analog To Digital Converter $
Digital Scale $
Linear measuring Device $
Base Plate w/attachments $
Adjustable Thumper $
Adjustable Microphone Mount $
Testing/Analysis Hours Hrs.
Testing Materials $700.00
Machine Shop Hours Hrs.
Total cost for Initial Concept Prototype $

35. Conclusion - Project Status
Refinement of Wants/Benchmarking/Metrics
Concept Generation
Testing and Evaluation
Physical Testing
Metrics
Concept Selection/ Design
Working Model
Future Activities - Scheduled

36. Project Goal
Satisfied Customers!