USF college of engineering EEL Engineering Design1 Term & Meeting Info: Spring M 6:30pm – 9:15pm. Angelina Colannino, John Hook, Kjersti Raabe, Brian Wagner

 Programmable, RFID controlled automatic feeder  User defined scheduled feeding time  Minimal product management required

1. RFID Tags must be in range  Must operate with material between tag and receiver 2. RFID receiver must operate without tag collisions 3. Timer Interface must be defined by user  Must store 3 set times  Must take input from interface 4. Motor Circuits triggered by logic circuit/timer 5. Power Supply

 Material must be thin enough to avoid interfering with RF signal.  Receiver must be mounted on front of module so that tags can be within 4” range.  Receiver must be mounted parallel to front of module in order to receive signal  Tags operating on frequency of 125 kHz

 Receiver must sense presence of RFID tags without error  The presence of more than one tag may cause tag collisions, which result in receiver error.  Test plans include tag collision experiment.

 Timer must be set by interface screen/buttons on front of module.  Screen must display current time, as well as interface for setting feeding times.  Timer must store up to 3 feeding times.

 Motor circuit must respond to trigger from logic circuit.  Logic circuit must take input from RFID receiver as well as timer.  Trigger must be produced when both timer signal is present and RFID tag signal is received.  Typical servos operate from PCM signals

 Primary:  120 VAC-4.5VDC (regulate between 4-6 V) step down transformer power supply  Secondary:  Battery Back-up (Alkaline)  4.5 V DC  42 hrs when in active use  10-year shelf life

Voltage Regulator LM7805 would make most sense for designing/regulating the power supply if using a chip to do so

 RFID Reader  VDC  Arduino Uno  Operating Voltage 5V  Input Voltage Limits 6-20V  Servomotors  4-6V DC  Maximum current draw is 140 +/- 50 mA at 6 VDC when operating in no load conditions, 15 mA when in static state file:///C:/Users/John-Hook/Desktop/ RFID-Reader-Documentation-v2.3.pdf Documentation-v2.2.pdf

 Self contained  Subsystems interface with each other  RFID serial connection with Arduino  Timing  Logic Circuit

 RFID sensor  Range  Interference  Tag collisions  Timing Circuit  Interface operation  Produce trigger  Storage  Servo Motors  Respond to trigger  Weight/strength

 Arduino Code vs. User Interface  Corkscrew vs. “Water Wheel” Dispenser  Drawer vs. Door  Scale vs. Clear Reservoir  Wi-Fi vs. Manual Setting  Alarm tone vs. Voice

 RFID sensor  Range  Interference  Tag collisions  Timing Circuit  Interface operation  Produce trigger  Storage  Servo Motors  Weight/strength

 Temperature  Place system in extreme temperatures and verify operation.  Accessibility  Test operation of lid on top of module.  Test operation of buttons/screen  Capacity  Test amount of food reservoir can hold

 Range  Read data from RFID receiver, holding tags at several different distances.  Interference  Read data from RFID receiver when different materials are used for module.

 User-defined Settings  Use interface to set 3 separate feeding times.  Demonstrate that the feeding times produce a trigger.  Storage  Demonstrate that feeder will store three feeding times at once.

 Trigger  Produce trigger from timing and RFID receiver to demonstrate that motor will respond.  Drawers  Demonstrate that motor can move the drawer.  Refilling mechanism  Produce trigger and demonstrate that refilling mechanism operates properly.

 Inherent  Overheating Motors  Battery Failure  Implementation  Probability of microcontroller failing (prototyping)  Timing Circuit  RFID Interference

Probability (Likelihood) 1 0 Consequence Performance Cost Schedule Potential Degradation Sys Reqt not Achieved Element Increase > 50% System Increase > 40% Element Increase Increase >10% x x x x High Risk – Severe disruption expected to performance, cost, and / or schedule even with risk mitigation plans in place. Moderate Risk –Expected disruption to performance, cost, and / or schedule can be overcome by implementing risk mitigation plans. Low Risk – Little disruption expected to performance, cost, and / or schedule.

 Double checking the code  Testing the code before finalizing the feeder

Probability (Likelihood) 1 0 Consequence Performance Cost Schedule Potential Degradation Sys Reqt not Achieved Element Increase > 50% System Increase > 40% Element Increase Increase >10% x x x x High Risk – Severe disruption expected to performance, cost, and / or schedule even with risk mitigation plans in place. Moderate Risk –Expected disruption to performance, cost, and / or schedule can be overcome by implementing risk mitigation plans. Low Risk – Little disruption expected to performance, cost, and / or schedule.

 Testing of  Multiple RFID tags  Range of the tags  Interference