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MEMBERS

• Advaya Krishna
• Mark Williams
• Sean "Kleinductor" Klein
• Utkarsh Sanghi

PROJECT CONCEPT

This project will expedite the checkout process in retail stores.
We will do this by using RFID tags and low range RFID sensors to uniquely identify products as they are placed in the C. A. R. T. S. An additional weight sensor will be included to improve the accuracy of the system.

MOTIVATION

The traditional checkout process:

• Creates a bottleneck in the retail experience
• Prone to human error when scanning items
• Self-checkout stations often need human input to handle edge cases

C.A.R.T.S. will:

• Eliminate waiting times for checkout
• Improve accuracy by automating checkout scanning
• Function with little to no human input

COMPETITIVE ANALYSIS

Self Checkout

• Requires users to scan each item
• Still requires large infrastructure for accuracy
• http://www.ncr.com/products/gm/self-checkout-systems/
• http://www.fujitsu.com/us/services/retailing/self/

Manual Checkout

• Requires Employee for Checkout

Online Shopping

• Requires shipping service
• Requires employees to process orders

TECHNICAL SPECIFICATIONS

• Arduino Mega, Arduino Leonardo
• ID-3LA Innovations RFID sensor with matching RFID card
• Sparkfun RFID USB breakout board
• 50 kg Load Sensor, with LM 741 Op Amp amplification circuit

• Arduino C code

• Serial USB Communication
• RFID Communication

REQUIREMENTS

Uniquely identifies a product as it enters or leaves the cart

• Lets the store and user know if there is a problem
• Keeps a complete list of products in the cart
• Must transfer product list from cart to checkout system

Must identify the product with 99% accuracy

Must keep an accurate inventory within 1 second of product movement

Must be able to identify products until a specified level of fullness is reached

Must transfer data to store checkout system within 1 second of connection

RISKS & MITIGATION STRATEGIES

To be completed.

TESTING & EVALUATION

To evaluate C.A.R.T.S., we used a combination of white and black box tests.

Our white box tests include a variety of sensor measurements under differing conditions, as well as actions to achieve full coverage of our project FSM

Our black box tests include a list of highly specific behaviors and actions, which will include the behaviors of an end user interacting with C.A.R.T.S.

For more information about the tests, view the Test Plan & Experimental Validation presentation.

Test Number 1:
• Requirement: Power On
• Use case: Turning on the device
• Test Sequence: From the off state, flip the power switch on. The cart should register an empty list of items and turn on a green status LED.

Test Number 2:
• Requirement: Power Off
• Use case: Turning off the device
• Test Sequence: From the on state, flip the power switch off. The cart should become inactive -- no state needs to be saved.

Test Number 3:
• Requirement: RFID Sensor Reliability
• Use case: Scanning items using the RFID and receiving feedback
• Test Sequence: Scan an RFID tag within 3 inches of an RFID sensor, facing the sensor. An audible "beep" should be heard.

Test Number 4:
• Requirement: RFID Sensor Reliability Plus Load Sensor Reliability
• Use case: Scanning items and placing them in the cart
• Test Sequence: Scan an RFID tag (attached to an item) within 3 inches of the RFID sensor, facing the sensor. An audible "beep" should be heard. Then, place the item in the cart, on top of the load sensor. Within 0.5 seconds, the item will be identified and appended to the list of items noticed in the cart.

Test Number 5:
• Requirement: RFID Sensor Reliability Plus Load Sensor Reliability
• Use case: Removing items and scanning them to take them out of the cart
• Test Sequence: For an item that is already on the "list of items" noticed by C.A.R.T.S., take the item off the load sensor, scan it within 3 inches of an RFID sensor (an audible beep should be heard), and remove the item from the system. Within 1.0 seconds, the item should be removed from the list of items in the cart.

Test Number 6:
• Requirement: Dealing with edge cases for RFID Sensor and Load Sensor
• Use case: Removing an item, but not properly identifying which item has been removed
• Test Sequence: For an item that is already in the "list of items" noticed by C.A.R.T.S., take the item off the load sensor, but do not scan it by an RFID sensor. No audible beep should be heard. Remove the item from the system. Within 1.0 seconds, an orange "Warning" LED should be turned on. Later, if the item is scanned by the RFID sensor, the item should be removed from the "list of items", and the "Warning" LED should turn off.

Test Number 7:
• Requirement: Dealing with stress tests for the RFID Sensor and Load Sensor
• Use case: Placing multiple items in the cart at the same time.
• Test Sequence: Up to four threads tests of "test number 4" can be executed together, in any order, and all four items scanned should be identified and appended to the list of items.

Test Number 8:
• Requirement: Dealing with stress tests for the RFID Sensor and Load Sensor
• Use case: Placing items in the cart quickly
• Metric: Time
• Test Sequence: Four invocations of "test number 4" can be executed within a 2.0 second period, and all four items scanned should be identified and appended to the list of items.

Test Number 9:
• Requirement: Identifying malformed user input
• Use case: Placing an item in the cart without scanning
• Test Sequence: Place an item in the basket without scanning an RFID tag by the sensor. No audible beep should be heard. A red "error" LED should signify that the cart has recognized malformed input.

TIME LAPSE

To be completed.

PRESENTATIONS & VIDEOS

• Project Proposal and Requirements
• Design & Architecture
• Mid-semester Project Status
• Test Plan & Experimental Validation
• Final Project Presentation
• Project Poster