Transcript
RFID Tracking System for Dock Doors Electrical Computer Engineering 409/410: Senior Paper By: Justin Johnson April 23, 2013 Sponsor: Mid South Marking Systems Project Advisor: Professor John Ventura, PE
I. Abstract RFID Door Tracking System for Mid-South Marking Systems, Memphis Tennessee. Justin E. Johnson, Christian Brothers University, Memphis, Tennessee The purpose of this project was to design and implement a Radio Frequency Identification System to detect movement through a specific entry point. The system was required to be non intrusive, provide detailed and accurate data through the entry point, to have minimal human involvement, and finally to be able to view the data via a webpage. The system was designed using the Java programming language to interface between the RFID reader and computer; the data was then converted using JavaScript into a user-friendly webpage. The components of the system after revisions were composed of an Impinj RFID Reader, two Times-7 antennas, and a wireless router. Through the experimental approach, we were able to make revisions to the Java code and fully implement the systems to the design specifications.
II. Customer’s Needs Founded in 1991, Mid South Marking Systems is the leading integrator of barcode and RFID products under the ownership and operation of Rick Summers. Mid South Marking Systems currently has a customer who wishes to track the movements of its employees who enter and leave through a specific dock door. There is currently no RFID software that specifically tracks the orientation of an RFID badge or its direction as it moves through the antennas’ selective range. Because of this, the recognition of a badge, when read by an antenna, gives flawed and inaccurate data. An employee could be merely standing in the range of the antenna with his/her ID badge, and it could possibly be read that the employee was in an area he/she
wasn’t. This customer wishes to be able determine when an RFID badge enters into an area and when the badge leaves— assuming that it is indeed an employee carrying the badge. Mid South Marking Systems’ needs are as follows:
The complete design and implementation of a directional tracking system that monitors when an RFID badge enters and leaves through a specific door.
To have detailed and accurate data identifying the date, time, location, and employee to whom the ID badge is assigned, and what point they enter.
To have a design that has minimal involvement from the employee and is physically unobtrusive to the dock doorway.
To be able to visually access and view the data in real time via a web based service.
Physically unobtrusive
X
X
X
Minimal involvement from employees
X
X
X
Allows For Detailed Accurate Data
X
X
X
X
X
Continuous Real Time Data Access
X
X
X
X
NEEDS
Zebra P430i Card Printer
Dashboard
Impinj Speedway Reader
Zebra RFID Card
Laptop Computer
Times 7 Antenna
METRIC
III. Needs Metric Matrix
X X
IV. Product Design Specification 1. The reader and antenna must be discretely located, as to not interfere with day-to-day actions. 2. The antenna must only read tags with the customer’s data written to them at various positions and orientations. 3. The database must collect and be able to maintain a live feed to the reader at all times. 4. The interface between the reader and antenna will have a host computer to run upon. 5. The software suite will control the reader and antenna activation via the host computers web application and allow for constant detection of movement either entering or exiting the door via Radio Signal Strength Indication values and calculations. 7. The web service will only be visible by the customer and will have secure access. 8. The data must be accurately presented via an on network dashboard.
V. Concept Generation Numerous decisions were made for this project. The first priority would be the choice of reader, antenna, and tag chip set for the RFID badge. The next factor was how to implement the directional tracking of the tag as the customer requested. The customer needs to know precisely when an employee enters and exits: this poses a challenge in itself. This challenge was solved with a set of Times 7 antennas mounted and continually reading when an object passes through their relative span. The final concern is the display mode, or what to do with the data obtained from the reader and antenna, and how to display the data efficiently so that the customer may view it in real time. The badge chosen for this system is made by Zebra Technologies and effectively operates in the UHF frequency range of 860-960 megahertz. This card, using a patent pending
design, can be read from up to 50 ft. away. This makes it the perfect choice for a system where range could be an issue for the antenna. This effective read range would improve the accuracy of the system. The Zebra badge contains an Impinj Monza 4QT chip set. This chip and antenna configuration has been proven to work regardless of the orientation of the tag. This consideration played a big role in the decision due to the lack of knowing which way the badge could be facing at any given time. Finally, the choice of this particular RFID badge improves security. The Zebra Technologies RFID badge includes a 48-bit unique ID feature that protects against card cloning and provides a card authentication method to uniquely identify every card; with this feature, there will never be a duplicate set of data of an employee. Accuracy and timing are highly important factors for this system, so the reader/antenna and RFID badge of choice all need to work seamlessly together. The RFID badge contains a chip made by Impinj Inc. The highly advanced features of this chipset led to further research into their other products. The Impinj speedway reader was the optimal solution because of portability and its unobtrusiveness for the system. The reader produces a radio signal that is transmitted to the antenna. The signal is then dispersed through the antenna. The passive RFID tag receives power from this signal and sends back a signal of its own to the antenna with the information encoded upon the tag. The reader then decodes the data received from the antenna, and this data is then sent to a computer or another device via LAN, serial, or wireless connection. The directional tracking of the tag is the main focus of the system, making it necessary to develop a threefold plan to track the tags. The first part of the plan involved using the reader’s Reader Signal Strength Indication values to calculate the position of the tag. Once this data was received, it was forwarded to a SQL Lite database. SQL Lite was chosen because of its wide variety of deployment capabilities and the price of the database. The database will then have data
pulled in real time from a web server, Apache Tomcat. Tomcat, like SQL Lite, was chosen for its wide range of deployment capabilities and cost effectiveness. Through research and testing, the antenna selected for this project was the slim line circular polarized antenna manufactured by the Times 7 Corporation. Circular polarized antennas have a greater receptive area as opposed to the other option linear antennas which have a further reading range. Due to the range of the dock or door being relatively small, a circular polarized antenna was chosen.
VI. Design and Modifications of System. The prototype initially tested used an Impinj Xportal reader and antenna combination. This unit was composed of an Impinj Speedway reader and Impinj linear antenna mounted and packed into a convenient small body. This unit was placed near a doorway and the RFID badges were read as the user passed by. Yet, during testing, it was proved that due to the nature of a linear antenna not having a wider range of reading that all RFID badges were not receiving the signal being transmitted by the antenna. Due to this, the Xportal antenna and reader package was not used and a new design was implemented. This new design was first conceived with the same ideals in mind and constructed out of stainless steel metal parts. The antennas used were circular polarized Times 7 antennas; they were mounted to the body of a frame along with an Impinj RFID reader. (See Figure 1.1) Through testing, the best height of the frame and position of the readers were determined and a final prototype was built, which included two Times 7 circular polarized antennas, one Belkin Net Gear router, and one Impinj Speedway RFID reader.
The database designed contained the fields of location, time, badge identification number, and personal information upon the employee. This database was designed to successfully store numerous badge inputs per day. All this information was then forwarded to a Java Server Page where the data could be viewed in real time. The page or dashboard contains a login feature where you must login before you can view any data. (See Figure 1.9) Once logged in, you are able to click upon the specific identification badge to display the times and dates of that badge. Behind the Dashboard, a background Java program is constantly running interfacing between the RFID reader, antenna database and dashboard. The user never sees this program and it is fully hidden from them. The user only is allowed to view the RFID Dashboard and due to this design no tampering of the data on the user side can be accomplished. The program uses a component called a Hash Map. The hash map is a data structure in Java that allows a particular value to be associated with another value forming a lock and key combination. This hash map is then forwarded to the database in the form of the parameters stated in the database. The background program functions as follows: -Set the connection to the reader from a specified text input file -Begin Auto trigger of reader -Make a database call to send the initial reads from the hash map to the database -If no reads wait and continue reading until values are obtained. -Once reads are obtained forward the information to the database for storage -Retrieve reads from database -Display reads in the form of a formatted table on the dashboard.
Employee
Mini Portal Antenna/Reader
Java Program
Passive RFID Badge
Database
Apache Tomcat Server
Web Page
Figure 1- Design Block Diagram
VII. Testing Plan The prototype-testing plan is divided into two sections. The first part of the prototype plan was to successfully assemble the hardware. The hardware system that was tested included connecting the Impinj reader and Times 7 antenna and configuring them to function properly. Next, the reader was connected to a laptop and the range of the antenna and RFID passive badge combination were tested by passing different RFID tags through the antenna’s range and
recording the data received manually. The Impinj reader and Times 7 antenna will be used during testing of various lengths and orientations of the RFID passive badge. After the hardware trials were completed, the second part of testing involved database testing. The Java program, “Portal-Track”, was modified to include Radio Signal Strength Indication values to detect the distance of the RFID Badge and present a threefold directional detection system. The data gathered was output to an SQL Lite database. This output of data was tested numerous times under various loads. Once successful, a Java based web page, dashboard was developed. This web page was placed inside the Apache Tomcat web server and displayed for the customer to view in real time on their private network. Network load testing is continuously in effect throughout the entire life of the system.
VIII. Project Timeline Order parts Assembly of Systems Testing Hardware Testing of Web service Writing Report August 2012
September 2012
October 2012
November 2012
December 2012
IX. Bill of Materials Item
Rated Price
Impinj Reader and Times 7
$4990.00
Antenna (2) Laptop
$500
Zebra P430i Card Printer
$5890.00
Zebra Passive Cards
$140
SQL Lite
$0
Tomcat 7
$0
Net Gear Wireless Router
$34.99 Total Retail Cost: $11,554.99
X. Prototype Cost Item
Cost
Impinj Reader and Times 7
$0 (Donated)
Antenna (2) Laptop
$0 (Donated)
Zebra P430i Card Printer
$0 (Donated)
Zebra Passive Cards
$0 (Donated)
SQL Lite
$0
Tomcat 7
$0
Net Gear Wireless Router
$0 (Donated)
Total Cost: $0.00
XI. Summary Health and Safety- the goal of this project was to provide tracking of incoming and outgoing badges allowed within a specific area of a facility. By implementing this solution, unwanted visitors and employees will be successfully monitored with the click of a button. This would improve the overall accountability of each employee in the facility. Social Analysis- This system would help increase the accountability of the employee upon their location in the facility, but the issue of privacy could be raised. Some employees may find that an RFID system would violate their rights, although the RFID system was not created for this purpose. It needs to be clearly stated which places that the RFID system will be used and where the stations will be located to insure that privacy is indeed kept sacred. Political and Environmental Analysis-The project poses little political impact besides that of privacy due to the fact that RFID badges can be reused. Sustainability and Functionality- The RFID system designed was designed to be used indoors due to the fact that the mounting of the components has no casing, yet it is rugged enough to be dropped or bumped into numerous times to sustain day to day usage. The system has a response time of 1 second, yet the updating of the dashboard can vary based on the traffic of the network, if the system is not contained within its on computer network as designed.
Appendix:
Figure 1.1 Circuit diagram for Monza 4 chipset.
Figure 1.2 Antenna design for Monza 4 chip.
Antenna
Monza 4 Chip
Figure 1.3 UHF Impinj RFID Badge
Antenna 1
Net Gear Router
Figure 1.4 Mounted on the frame, antenna, reader, and router side one.
Figure 1.5 Side view of the frame.
Antenna 2
Impinj RFID Reader
Figure 1.6 Back view of the frame.
Figure 1.7 Frame in comparison to average door.
Figure 1.8 Dashboard demo display of information.
Figure 1.9 Login page to access the dashboard.
Works Cited "The Monza 4 RFID Tag Chip Family." Monza 4 UHF RFID Tag Chips. N.p., n.d. Web. 05 Dec. 2012. "New UHF Gen 2 RFID Card." New UHF Gen 2 RFID Card. N.p., n.d. Web. 05 Dec. 2012. "Performance Class Card Printers." Performance Class Card Printers. N.p., n.d. Web. 05 Dec. 2012. "Slimline A6031 Circular Polarized UHF Antenna." Times-7. N.p., n.d. Web. 05 Dec. 2012. "Speedway Revolution UHF RFID Reader." Speedway Revolution UHF RFID Reader. N.p., n.d. Web. 05 Dec. 2012. "UHF RFID Products Supporting Worldwide Operation | Impinj." UHF RFID Products Supporting Worldwide Operation | Impinj. N.p., n.d. Web. 05 Dec. 2012.
