Automated Multiple VCR
Master Control Unit
Final Report
Project Team: May01-13
Submitted: April 16, 2001
Client: ISU Engineering Distance Education
Paul Jewell
Faculty Advisor: Dr. Edwin Jones
Team Makeup:
David Douglas (CprE)
______
Matthew Engelbart (EE)
______
Hank Huang (EE)
______
William Ogier (CprE)
______
Executive Summary
The Engineering Distance Education program at Iowa State University in Howe Hall is dealing with the issue of multiple VCRs that cause problems when recording or duplicating many tapes simultaneously. The current recording facilities consist of thirty-seven different VCRs from three different manufacturers in two different rooms. It is necessary for the individual in charge of recording lectures to manually press the buttons on each VCR since using a single remote control will not work. This is highly inefficient and results in timing discrepancies between the different tapes in each VCR. A solution is necessary that allows the individual in charge of operating the VCRs to do so without timing discrepancies between the tapes. The solution designed will save time, increase the efficiency of VCR operators, and reduce the recording errors made during the copying of lectures each day.
The project was fueled by the requests of the Engineering Distance Education program and all decisions made were an attempt to meet those requests. Based on planning and designing throughout the first semester, the design team began working on the solution in January 2001. Although some ideas from the original design did not make the final design, many of them were kept in the design and are reflected in the final work. The overall idea of the solution was retained, but some of the details were changed when differences in theoretical design and actual design occurred during development.
This project consists of a hardware/software solution that will communicate with different banks of VCRs via infrared emitters. The software provides the graphical user interface (GUI) that the VCR operator will interact with. Through the GUI, the operator can make any selection of VCRs to control and do so as if the computer screen were a single remote control that can control all of the VCRs simultaneously. The GUI allows for the addition of new VCRs into the work environment because it has the ability to record new remote control protocols and assign them to the corresponding VCRs.
The hardware control unit consists of logic unit circuitry and a power supply. The circuitry is made up of two main sections: IR signal processing and VCR addressing. The signal processing portion of the hardware allows for remote control signals to be received as well as emitted through the proper IR probes. The control unit needs to receive signals when recording and storing the IR protocols of VCRs for each basic VCR function. It will then emit the stored signals appropriate for the function desired to the VCRs desired, all manipulated by software input. The addressing portion of the hardware is necessary to direct IR signals to the desired VCR. The circuitry is powered by a commercial power supply that is enclosed into a metal casing with the circuitry that is suitable for mounting in a standard VCR rack.
The software communicates to the hardware portion of the solution via the parallel port of the computer. Three types of communication take place over the port: incoming infrared waveforms, outgoing infrared waveforms, and VCR addressing. Incoming IR waveforms are sent from an infrared receiver located on the hardware and passed to the computer port for storage. Outgoing IR waveforms are the signals from the computer to the control unit that tell the VCR what function to perform. The VCR addressing points the corresponding outgoing IR waveform to the specific VCRs that need to be controlled.
The project has been completed to the best of the ability of the design team in the given time frame. Initial hardware testing as well as initial configuration and programming of the software proved to be tedious. The solution has been put into use at the Distance Education program video recording lab in Howe Hall. The solution is self-sustaining and should require little maintenance to keep it running. The Distance Education staff can properly operate the hardware/software and will continue to do so in the future. Should the need arise, repairs should be possible with the help of the user documentation provided with the solution.
Acknowledgment
The ISU Engineering Distance Education department provided significant financial assistance. Joel Scott provided technical assistance for possible methods of developing a solution, as well as explaining the setup of the current system in use and the goals for the future system. Dr. Jones and Paul Jewel contributed a lot of time and advice throughout the project development.
Definition of Terms
VCR – Video cassette recorder – machine that records video signals
IR – Infrared – light spectrum through which VCR commands are transmitted
LED – Light emitting diode – component which transmits IR signal to VCR
C++ -- Common programming language
GUI – Graphical User Interface
Introduction
The Engineering Distance Education program at Iowa State University in Howe Hall is dealing with the issue of multiple VCRs with varying models that causes problems when recording or duplicating large numbers of tapes. These VCRs are located in different rooms making it difficult to synchronize duplication. In order to solve this problem, a hardware and software solution is proposed to control the existing VCRs, as well as allowing for expansion up to sixty-four VCRs. The goal of this project is to develop a user interface that will allow the control operator to control a VCR or a bank of VCRs with a click of a mouse button. The user interface will operate on a Windows based operating system in the control room. The control box will be nearby and will route the signals and commands to the designated VCR, whether it be in the same or different room. The control box will be fit into a metal casing that will be the equivalent in size to a regular VCR so that it can slide into the rack with the other VCRs. Cable will run from ports on the control box to each of the VCRs where an IR emitter will be attached firmly to the front panel of the protocol sensor. This solution should allow the operator to accomplish his/her task in a timely fashion.
Technical problem:
The Engineering Distance Education Learning facility deals with a large quantity of tapes that need to be recorded and sent out daily. Manually controlling each of these VCRs becomes a problem when synchronizing multiple tapes as well as the inconvenience factor of dealing with multiple makes and models. This system will have the capability to select or deselect which VCRs are needed at any point in time from one main control unit. The control unit will interact through the parallel port of the PC using software written in Borland C++ version 5.0 by recording IR protocols from the VCR remotes and replaying the appropriate learned signals to the specific VCRs. The control unit will consist of various off-the-shelf components including a power supply, diodes, resistors, capacitors, as well as various IC chips. The 5 V, 1.5 A power supply will be mounted inside the metal casing to allow for easy transport and handling. To resolve possible heating issues within the casing, a fan will also be inserted and will run off the 5 V power supply. The casing will be sized so that it will be able to be inserted into the rack-mounted shelves where the VCRs are located. Infrared LEDs from the control unit will pass signals to the VCRs without interference by being affixed to the IR probe of each VCR near the protocol sensor using Velcro. The IR LEDs will all run to the back of the control unit where each will be fixed to an individualized port.
Operating Environment:
The Engineering Distance Education Learning facility is located in Howe Hall, so there should be no problems with “extreme” conditions. The control unit will be placed within the rack-mounted shelves along with the other VCRs and the PC running the user interface will be in the same room. The room will be kept at an average of 70˚F, which will allow all the equipment and machinery in the operating room to work collectively without any overheating issues. There should be no humidity issues as well.
Intended User and Uses:
The Engineering Distance Education program will be the initial user, which may be expanded into other departments across campus following implementation of a successful solution. This will allow the individual in charge of taping sessions to record or duplicate lectures without timing conflicts. This will include initiating the recording and stopping of any number of various VCR models at any particular time.
Assumptions:
· All VCRs must be in proper working condition
· Standard VCR commands will be implemented: stop, play, record, fast forward, rewind, and pause
· The user is computer literate and can operate software and hardware with minimal effort
· The Engineering Distance Learning program will have adequate funds to acquire necessary items to implement the project
· VCR commands will be learned properly by the software
· Remote control commands will not need be pressed continuously
Limitations:
· The system will be expandable only to sixty-four VCRs per control box
· The control unit will not be able to receive any feedback from the VCRs that it will control, forcing the user to insure the VCR is properly prepared to function as desired
· Access to the distance learning facilities
· Knowledge of Visual C++ is limited amongst group members
· The group has minimal knowledge of VCR remote control protocols
Design Requirements
Design Objectives:
User interface – A software interface produced remote control, which allows the basic six VCR commands and recording of IR protocols from the actual VCR remotes. It will operate on an existing PC system located within 1364 Howe Hall. The user interface will be created using Visual Basic, and the parallel port interface with Borland C++.
VCR control unit – A device that will route signals to all of the appropriate IR emitters after receiving commands from the user interface through the parallel port of the PC. It will also be able to send signals from VCR remotes to the PC via the parallel port to record the commands of new VCRs added to the system.
Functional requirements:
· Be able to learn commands when new VCRs are purchased
· The ability to group different VCRs into VCR banks
· Expandable for new VCRs
· Perform the six basic VCR functions
· Control anywhere from one to sixty-four VCRs at once
· Control VCRs in different rooms
· Easy to use system for an individual with minimal technical knowledge
· Robust design to eliminate or minimize the need for maintenance
Design Constraints:
· Signal loss due to length of wire between control box and LEDs
· Control unit to fit into the approximate dimensions of a standard VCR
· Control box will have its own power supply
· Communication with the PC is based around the parallel port capabilities
Measurable Milestones:
· Operating a VCR straight from remote control through the signal recorder to the IR LED. This milestone is met when a VCR can be controlled via a remote control signal passed into the control unit infrared receiver, through the signal processing portion of the control unit, and then emitted to a single VCR.
· Talking between the computer and control box to establish a reliable connection measured by the ability to control a single IR emitter. This milestone is met when the software can manipulate the IR emitter on the control unit. This confirms proper parallel port communications.
· Controlling a single VCR via the control unit to perform the basic six functions. This milestone is met when the computer stores all six functions of a single VCR, and these functions can be sent to the VCR through the signal processing circuit.
· Maintaining adequate power levels to multiple IR LEDs to allow the signal to be picked up by the IR sensor at the VCR. This milestone is measured by the ability to send a signal to all VCR LEDs and have the VCRs respond to the command.
· Controlling multiple VCRs at once so that all machines can be operated at once. This milestone is met when all VCRs work properly based on the commands entered at the software interface.
· Successful testing of the final product. This milestone is met when the software and control unit are in place at Howe Hall and ready to use for real-life production purposes.
End-Product Description
The solution is a software package with an accompanying hardware unit of off-the-shelf components that will allow a user to control multiple VCRs at once by controlling them from one centralized location, a desktop computer. The software allows the user to control any different number of VCRs at any one time, utilizing such commands as play, record, stop, fast forward, rewind, and pause. The hardware unit allows the software to record IR protocols of new makes and models of different VCRs. This product is a powerful tool for commanding multiple VCRs at the same time with the comfort of sitting behind a PC. It is easy-to-use, setting it up only requires it to learn the VCR commands by pointing and clicking the VCR remote at the control unit