280 likes | 420 Views
Puzzled. ELM-4702 Senior Projects 2011 Eric Babski ~ Ben Gagne ~ Erik Artus. Agenda. Background Problem Statement Problem Solution System Diagram Detailed Sub-system Descriptions Schedule Responsibilities Budget Future Improvements Questions. Background. Holyoke, Massachusetts
E N D
Puzzled ELM-4702 Senior Projects 2011 Eric Babski ~ Ben Gagne ~ Erik Artus
Agenda • Background • Problem Statement • Problem Solution • System Diagram • Detailed Sub-system Descriptions • Schedule • Responsibilities • Budget • Future Improvements • Questions
Background • Holyoke, Massachusetts • Produces 30,000 Puzzles a Day • Inspect random samples from each machine • Puzzle piece sizes vary from 0.8”-2.0” wide 2.0” 0.8” 2.0” 0.8”
Problem Statement • Our team was given the challenge to design a device that counts puzzle pieces quickly and accurately. Requirements • Require no more than 1 operator • Easy to implement into factory • Over 100 pieces/min • 100% accurate • Budget = $1000
Problem Solution We are using an electronic microphone to listen for the pieces as they are conveyed through the device. Sub-Systems • Air System: to convey pieces • Microphone: to count the pieces • LCD User Interface: to display the count
Research • No device currently exists for counting puzzle pieces. • Microphone technology is used for quality control in: • Cereal manufacturing • Coffee manufacturing • Instrument production • Other Concepts • Conveyor w/ limit switch • Low reliability/accuracy • Optical Scan • Too Expensive, complicated • Laser Beam • Too expensive, dangerous
System Diagram Piece Air Software Microphone Sound Plate Catch Drawer User Interface
LCD Display Prototype Design Reset Count ON/OFF Sound Plate Pieces In-Feed Hopper Microphone Air Inlet Feed Tube Catch Drawer
In-Feed Hopper Details • Stainless Steel • Back and Side Walls • Rounded Bottom 3.2”
Feed Tube Back Plug 2.5” • Material: Clear PVC • 12” x 2.5”od • Mounted angle 5° • Backplug = Nylon 12” Air Inlet
Pneumatics Flow works Simulations • Optimum Nozzle Location • Flow at Piece Inlet • Velocity at the end of the tube Minimum pressure to move a 2” piece = 10-15psi Piece Inlet
Catch Drawer • Material: Wood • Purpose: Catch pieces & dust • Simple two piece design that interlocks. Pieces • Metal grate allows dust to fall into the drawer below. Piece catcher Metal Grate Dust catcher
Sound Plate • Used to create a sound wave every time a piece hits it. • Had to be made from a material that would make a distinct sound but not resonate. • Mounted at an angle to reflect counted pieces to the catch drawer.
Sound Plate Testing ………………….... • Wood • Metal • Plastic • Cardboard ………. …………………... ….. 1 = Bad 5 = Good
Microphone Requirements • Must run off 5 volts maximum. • Wide frequency range. • Sample at 1000 Hz. • Small & Replaceable
Microphone Details • WM-52B • Specifications: • Runs on 2.5VDC • Frequency: 20-16k HZ • Impedance: Less than 2.2kΩ • Available in lab
Microphone Testing • We used LabView to test the output of our microphone. • Dropped 3 pieces. 1 2 3
Results Our LabView test results show… • Noise • There is some noise produced at the output of the microphone. • Filter • Gain • We found that the voltage spikes we were getting were in the 500mV range. Secondary Spikes Outside Noise
INA 126P Op-Amp • Needed to run single-ended. • Between 0-3 volts at the supply. • Readily available. G = 5+(80k/RG) Before Amp (300mV Spike) After Amp (2V Spike)
Circuitry LCD Power Supply +3v DC Voltage Regulator Power Supply +12 v DC Op-Amp Mic
User Interface • Requirements For LCD: • Need at least 12 Characters • Inexpensive • Specifications: • High quality STN 16x2 character LCD • 3.3V power supply • Cost $14 • Available in lab
Software Counting Sequence #define SIG_THRESHHOLD 950 #define tink_delay 50 int count = 0; unsigned intmic_result; mic_result = ADCR; if (mic_result > SIG_THRESHHOLD) { count++; LCD_delay_ms(tink_delay); }
Responsibilities • Eric Babski • Team leader • Solidworks drafting • Presentation design • Fabrication • Scheduling • Erik Artus • Electronics • Software design • Circuit board design • Testing • Ben Gagne • Purchasing • Fabrication • Solidworks drafting • File Organization
Future Improvements • Larger catch drawer • Smaller Infeed Opening • Table Top Hopper • Adjustable Threshold • Automatic Noise Calibration
Thanks to: • Edaron Inc. • Professor St. Denis • Professor Wolf • Bob Royce • Fellow ELM Students • Friends & Family