final report

FINAL REPORT

ABSTRACT

This project is an attempt to use a wireless protocol to design a system that will monitor and track robots within a specified, confined area. The robots will be monitored using transponders, a transceiver, and a central computer that will process information about the movement and course of the robots.

There are two main problems that must be addressed in order to successfully complete this project. The first problem involves choosing the appropriate wireless protocol. Many such protocols exist and include, but are not limited to: Global Positioning System (GPS), Radio Frequency Identification (RFID), Infrared, and Micropower Impulse Radar (MIR). The group has chosen to use RFID. The group's reasons for why RFID was chosen over the other options are explained in the Introduction below.

The group expects that the project can eventually be expanded to serve a larger scale purpose. For example, the technology could be used by correctional facilities to keep track of where their patients are located within the facility. Therefore, it is important to choose a technology that will serve on both a smaller and larger scale.

The second problem involves writing the necessary software so that the transceiver and the transponder(s) can communicate the necessary information to the main computer. In the case of the project, the main computer will be a laptop. On a larger scale such as the correctional facility, the main computer might be a computer accessible by security and staff, which would keep track of where all the patients are located. Also, the computer would need to able to support information sent by multiple transponders to multiple transceiver devices at once. For the project, electronic toy robots that can move on their own will wear the transponders.

While the group intends to solve the two main problems, there are additional problems that the group will encounter. Such problems include getting sponsorship and/or funding to purchase the necessary parts. The group intends to address all such problems in an attempt to successfully develop a method by which the robots can be tracked using wireless protocols.

INTRODUCTION

Over the last few decades, the use of robots to model real-life scenarios has become an increasingly useful tactic used by companies worldwide. Robots have been used to navigate unfamiliar environments, carry out a wide variety of tasks at once, and perform countless other functions. In the case of the Multiple-Robot Network, robots will be used to model a large-scale facility that requires the tracking of patients or objects (where the patients/objects refer to robots) using wireless protocols.

The idea of tracking objects has become increasingly important in this market, and extensive research and background information is necessary for a more efficient and faster system. RAdio Detection And Ranging, more commonly known as RADAR, is the method of using radio waves to detect the existence of an object and then to find its position in relation to a known point. Stationary or moving objects can be detected by means of transceiver. In fact, the precise position, speed, and course of the object can also be obtained.

There have been many technological advances made using transceiver detectors. Our objective is to seek and improve upon the present technology by creating a tracking system for a network of robots that is efficient, high-speed, and exceptionally reliable. Among the technologies previously considered, Radio Frequency Identification (RFID) will be used to monitor the system because of its reliability and its significant advantages including the noncontact, non-line-of-sight nature of the technology. This technology would require radio frequency transponders on each tracked robot, radio frequency reading units to be placed strategically throughout the tracking area, and a central computer. The central computer would be used to display location information for the robot at certain time intervals.

Key parameters of the system will include low frequency bands of 100-500 kHz. While this will result in a low reading speed, it is a more cost efficient method. In addition, a power level of 100 - 500mW will be used because it is generally the accepted value in the United States.

SELECTED TECHNOLOGY FOR THE MULTIPLE ROBOT NETWORK

Radio Frequency Identificiation (RFID)

Radio Frequency Identification (RFID) is a system that carries data in suitable transponders, generally known as tags, and retrieves data by machine-readable means to satisfy application needs. In the Multiple Robot Network, the RFID system will be used to track the course of a robots movement.

The tag is embedded with an antenna or a coil that emits radio signals that is received by the transceiver. The transceiver has a decoder, which interrogates the data encoded in the tags integrated circuit, and the data is passed to the central computer.

Design Objectives

The design must include:
*Transponders would need to be worn by all robots being tracked.
*Transceivers would need to be placed strategically.
*A central computer would be needed to process all transactions between the transceivers and the transponders.

Functional Requirements

*The transponders would need to be encoded with unique identifiers in order to distinguish between all persons.
*A sufficient number of transceivers would have to be placed to cover the entire area since the RFID transceivers have a range of only two feet, each.
*The transceivers must be able to read and identify the identification code sent back by the transponders.
*The transceivers must be networked to some central computer informing it of which transponders are in which locations.
*The computer must be able to accept signals from all transceivers.
*The computer must be able to display location information upon demand.
*The computer must be able to set off an alarm in case of a perimeter breach.

The system could be designed for many possible applications. For example, the system could be used to track people inside a confined area such as residents of nursing homes. This design is intended to insure the safety of patients in healthcare facilities by providing the locations of the patients to the staff.

Design Requirement for Hardware

The hardware requirements for this design will be a Sentinel-Prox Medium Range (MR -1824) reader (transceiver) and two Prox-linc CS (transponders). A central computer is also needed to display and update the locations of the tagged objects.

Design Requirement for Software

The software requires will be written in C/C++ or Assembly. The program used to generate the connection between the transceivers and central computer.

Design Constraints

The group decided to use RFID technology. The transceivers for RFID technology will be placed in the box so that there will not be major obstacles between the tags and the transceiver. The reason why the group will not place major obstacles between the tags and the transceiver is the transceiver being used has low range and strength. Transceivers of greater range and strength can be used but that is not necessary for the senior design. The purpose of the project is to show that tracking of motion is possible using RFID technology. Tags of greater strength are available and can be used if required. Also, there is neither enough space nor the need during the final display to use a tag with greater range. Another reason to use the low range tag is the price constraint.Tags with greater range cost more.

Originally, the group was going to design and build robots that to be tracked.
The group eventually decided to purchase toy robots because of insufficient time necessary to build the robots.

This design can be improved. One way to improve the design is to substitute the short-range transceivers with longer-range transceivers. In the group's case, the group is using a short-range transceiver (MR-1824) due to limited budget. The group had problems getting sponsorship and/or funding to purchase the more expensive parts. Therefore, to counter this limitation, the group is using the Sentinel-Prox Medium Range (MR-1824) transceiver.

System Parameters

The Sentinel-Prox Medium Range (MR) reader stands out among its competitors for mid-range proximity readers. The MR-1824 is in a class all to itself with an industry best 18-24 inches in a compact 8 X 8 X 1 inch enclosure. No more misreads, fumbling to get the card closer to the reader, the MR-1824 reads at maximum range every time. And, it does so at an unprecedented 600 mA's at 12 VDC. It is designed for indoor or outdoor mounting applications.

The MR-1824 reader electronics are potted with a UL-approved epoxy to seal them against adverse environmental conditions. It is manufactured in an ISO 9000 certified facility providing for the highest quality standard. It is highly reliable, warranted for life and comes in dark gray. The high tech styling of this reader, combined with its superior range, is impressive. It offers Wiegand and RS-232 protocol interfaces and is compatible with all standard access control systems.

Critical Components

All critical hardware necessary for this project has been enumerated above. The transceiver and transponders will be ordered and the robots will be purchased from a toy store.

Test Procedure

Various test procedures will be performed to insure the success of the group's project. Such tests include, though may not be limited to:
*Testing various materials to determine if the materials interfere with communication
*Testing the range of the transceiver from all angles to determine the range of the transceiver from all angles
*Testing the computer to make sure the computer can compute the location of a transponder within a sufficiently short period of time

Major Design Risks

The transceiver being used for the Senior Design project will need to be reprogrammed to be able to track the motion of the robots. It will be necessary to understand the existing program of communication between transceiver and tags in order to properly reprogram the transceiver. The modified or added program will have to be able to work with the existing program. The major risk is that if the original program of communication is disrupted then there might not be any communication between the tag and the transceiver.

Due to financial constrain the transceiver being used have a range of 2 feet. This range is sufficient for the Senior Design purpose. The other major concern is that the transceiver's range of 2 feet is not a 360-degree circle. The range drops to only 1.5 feet at certain angles from the transceiver. Consequently, the transceiver will have to be placed so that the entire area can be covered.

CONCLUSION

This project is especially relevant to medical and correctional facilities that need constant surveillance. While the project being done by the group is of a much smaller scale the results of this project can easily be scaled up. Though the project involves a robot tracking and finding an object the results of the group's efforts can be applied, for example, to hospitals that need to keep track of their patients.

Indeed, the major strength of this project is that it can easily be scaled up and down to fit the needs of the facilities that decide to use such a tracking system. Also very important is that the parts are not very expensive. Hence, on a larger scale, the group's design could be sold for less than other systems and also earn a greater profit.

The major weakness is the group's lack of knowledge about RFID technology in general. Also, since the group has not found examples of similar efforts performed by other groups or companies, the group has no base from which to find information. Hence, a lot more time will be spent trying to become familiar with RFID technology and finding information.

ssThe most important part of the project is that the group is developing a technology that is not used in industry already. In other words, health facilities do not presently use RFID technology to keep track of their patients. A second aspect of the project is that other groups can build on whatever this project accomplishes. New, and better, technologies may be discovered that might further improve the group's final design. Consequently, other groups will be able to take what this group will have accomplished and improve upon it.