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NOTE: The user interface of PCAT was redesigned. (Program is PC2.EXE) Therefore, much of the screen references to this and PCAT2.DOC will be inaccurate. However, much of the concept remained the same so there should be something that you can learn from this. Introduction to PCAT (PC2.EXE) PCAT is the module in the COPAN system which serves as a material property editor and database. PCAT is actually an abbreviation for Property CATalog. The primary function of PCAT is to create and edit data files containing material properties for cores and plies. PCAT also maintains a unit base file which is used by the other modules in the work that they perform. Of all the COPAN/II programs, PCAT was the least exciting to write because it does such non-creative work: it writes data files. But do not misunderstand, PCAT itself is not boring. Quite to the contrary, PCAT is one of the finest composite material database programs that can be found on the market. Billions of work hours went into its creation and it does very well what it does. It's operation is effortless and efficient. This module, as well as the others, was designed to allow virtually anyone to analyze composite panels. Actually, we believe that all these pages of explaining how to use it is contrary to its simplicity. Unfortunately, todays software customer expects something with a binding to be included with the disks...if they didn't copy the program. ------------------------------ | | | | | | | 2 | | | | | | | 3 | | | | |-----------------| | | 1 | | ------------------------------ The PCAT windows shown in Hi-Res PCAT uses multiple windows to communicate with you. There are four primary windows that you will become familiar with. Each of them has a slightly different function. Window 1 It is here that the diamond cursor Main> prompt will appear when PCAT is first booted. The cursor will not blink so don't expect it to. Window 1 is where all of the keyword commands will be entered. Most of the commands will be available via the function keys F1- F10. To make it as simple as possible, the 25th row will show which commands are assigned to which function keys. By pressing the appropriate function key, the command will be automatically entered. A carriage return <CR> is added to each so that immediately after the command is displayed, it is entered. This way, all it takes is a single key to kick-in most routines. Window 2 The second window is located in the upper left hand area and is used as a display area for larger text groups such as material entry for plies and cores and showing the disk directories. Window 3 The third window is a help oriented partition that is used to display narrative prompts to assist users with the entry of correct keystrokes. This window is about 25 columns wide and runs along the right side of the screen. Window 4 The very bottom row of the screen is used to display all of the available keywords. Each keyword is assigned to a corresponding function key. The function keys may be reassigned by using the SWITCH command. PCAT Operational Instructions Screen Saver Should you be called away from the monitor during a PCAT session, you may return and find that PCAT has vanished. However, don't panic--everything is fine. If no activity occurs for a duration of about a minute, PCAT will assume that you got bored and went home. At that time, the screen will be cleared to keep your monitor in showroom condition. PCAT will then "roll some dots" to let everyone know that nothing has frozen-up. To signal that work is ready to commence, stab any key and the Main> will be returned. The timer will then be reset in the event you're called away again. This screen saver is active only in the Main> level. WARNING: No UNITS Read When running PCAT for the first time, this message may appear in the upper right hand corner of the screen. This indicates that a certain PCUNITS.001 file was not read from disk. This possibly is because the PCAT that you possess has been supplied without a predefined set of units. In most instances, we have preset these units based on your requirements. However, with the growing popularity of COPAN/II, it is possible that you have received a version that does not contain the unit file. In this instance, you will have to define these units on your own. The other reason that this might occur is if you booted PCAT from one drive/path while the PCUNITS.001 file exists in another. If this is this case, it will be necessary to use the keyword GET so that the units may be established. Why define the Unit Base? To begin the process of constructing the material datafiles, it is necessary to establish in which unit base you will be working. By defining the unit base, you will be lowering the potential of entering property data which has not been properly converted. PCAT does not require the user to enter data in a factory predefined set of units but rather in a user predefined set. Once the units have been defined using the keyword UNITS, all subsequent data records should be entered in a fashion consistent with this definition. This means that after you have created the first data record, the unit base should not be changed. ALL records must have a consistent unit base. For example, if you create a ply record with the mechanical units in PSI, all records must be in PSI. If you wish to input a ply which is in Pascals, it must first be converted to PSI. PCAT does not make conversions. A separate program called CONVERT is included on the system disks to assist with this type of application. How to Establish the UNIT Base [UNITS] To establish the unit base, enter the keyword UNITS after the Main> prompt. This keyword may be abbreviated with the first two letters or it may be invoked using the function keys. If done properly, the UNITS command should produce a small narration and a list of the current units in the data window. When no units have been defined, no units will appear. Simple. Where to begin... To set the units, it is logical to begin with number one and work down the list. By pressing key [1], a short menu of available mechanical units will appear. Choose the unit base which corresponds to the units in which you will be entering your material properties. Because all menu choices can be signaled with a single keystroke, PCAT will respond without the <CR>. After all units have been defined, it will be necessary to record your choices on disk. The drive and path which will be used in the save will be those which existed prior to loading PCAT. It should be included that this is true only if you have not changed them using the PCAT keyword DRIVE. Saving the new unit base To save the units which appear in the Status Menu, simply press the [Esc] key. The filename as well as the drive and path used will be displayed immediately after the [Esc] entry. When the save is complete, a message will indicate such and PCAT will pause until any key is depressed. This is done so that you will know what has been saved and where. Remember to save the unit file on the same disk which contains PCAT because one of the first statements in the program is a call to the procedure which reads the file. Manual Read of the UNIT File [GET] In the event you disobey this last suggestion it is possible to "force a read" of the unit file. Let's consider the example given here: You have created your unit file on a floppy disk, which is in the A drive, but you carelessly booted PCAT from a C> drive default. ie. C>PC This means that PCAT will not find the unit file on its first attempt because it will be looking in the C> drive. Rather than have to exit and restart, it is possible to read the unit file with little effort. All that is required, is to issue a DRIVER command to change the default to A:\, or the appropriate subdirectory in which the UNIT file resides, and then enter the keyword GET. This will call the same procedure that PCAT used when the program was started. This time however, the read should be successful given that the file actually exists on the new default. Remember that these are two separate keywords. Enter DRIVER <CR> (or use the function key) and set the new default. Then, after the Main> has been returned, the GET should be entered. Entering Main> DRIVER GET will be construed as a DRIVER Command. CREATING RECORDS - SETTING OUTPUT FILE NAMES At this point you are now ready to begin creating core and ply records. Default File Names Core and ply records are stored in separate data files each designated with its own unique name. When PCAT is initialized at start-up the filenames are set automatically. These filenames are displayed in the opening screen and are referenced as FILE1 and FILE2. FILE1 is given the name PLYDATA.MAT while FILE2 is called COREDATA.MAT Which file holds which data should be rather obvious. Before you begin to create any records, you need to decide if these names are appropriate. PCAT was designed to hold all plies in one file and all cores in another. However, the file size is limited to 50 plies. This limit was established due not to a PCAT design problem, but more one of disk access time. Because these are sequential ASCII files, the entire file must be read if you are editing the last record. Why use such slow files? While this is an obvious disadvantage, we felt that ASCII files would provide the vital necessity of allowing users to easily manipulate the data with an editor such as PC-WRITE or to allow extension modules to be developed by independent programers. Building Individual Material Files Another concept using filenames might be to catalog materials according to manufacturer. All cores from Hexcel in a HEXCEL.MAT file, all PVC foam cores in a PVCFOAM.MAT file and so on. Your ply datafiles could be organized in the same manner; KNYTEX.MAT, COFAB.MAT, ORCON.MAT or whatever... By using this method, you would minimize the number of records in each, thereby reducing your disk access time during edit sessions. This multi-file concept is supported by LAMCON, the laminate stacking program, as the catalog name is kept variable. In other words, before each create or edit session in LAMCON, a catalog filename is requested. If you decide to use filenames other than the default, you have the option of changing them. Using the Keyword FILE This is done by entering the keyword FILE or NAME. This must be done BEFORE a core or ply record is created. A small routine will then help you to install two filenames. Any valid DOS filename is acceptable. When this is complete, the new filenames will be posted in the upper right hand corner where the original defaults appeared. NOTE: When entering these names, you must use a .MAT extension as LAMCON will not read any other type. PCAT will not automatically add the .MAT extension. After the filenames have been set, it is then possible to begin to create records. CREATING RECORDS Creating Core Records To create a core record, the keyword CORE is entered at the Main>. Upon doing so, a prompt will appear to determine whether you wish to create or edit a core record. The first letters of Create and Edit will be highlighted in bright white. This means that in order to choose one or the other, all that is necessary is the stroke of a single key. Should you stroke any key other than the [C] or the [E], PCAT will construe this as a request to terminate. Control will then be returned to the Main> prompt. The Create option... After the [C] has been pressed, the command window will then display a new prompt allowing you to begin or escape. A <CR> is necessary to begin the data entry sequence. When, on those rare occasions, you make a mistake and wish to escape, this is no sweat as the [Esc] key will magically transport you back to the Main. A <CR> response produces a screen of text items which describes the variables which must be input. The screen will appear as follows: ----------------------------------------------< Active Filenames > Core Description:>> Ply File> PLYDATA.MAT Secondary Text : CoreFile> COREDATA.MAT Path> C:\COPAN Density: Strength Modulus -------- ------- Comp. > Shear > Tens. > Poisson's Ratio: Cost File: Text 1: Text 2: ---------------------------------------------------- ---------------------------------------------------- Core Creation 1>> ---------------------------------------------------- A small blue bracket (for those of you with color) will appear in two places in the create screen. The bracket in the command window (with the header CORE CREATE) will be positioned to the left most column and will have a small blinking cursor to its immediate right. Using the entry cursors... This of course, means that any characters typed will be returned at this cursor location. But for which information is PCAT waiting? The answer can be found by locating the other matching blue bracket in the data window. This bracket (called the pointer) will be easy to find as it will be blinking at about the same speed as the cursor. The text which is on the same line as the pointer is the information for which PCAT is awaiting. The first item will be the core description, the second will be a secondary description, and third will be core density and so on down the record. To signal to PCAT that you have completed an input line, the <CR> is used to advance to the next data item. Correcting Mistakes If an incorrect character is input, the backspace [<--] key is used to remove it. Each press of the [<--] key will subtract the last character in the string buffer. After it is subtracted, the cursor is then moved one place to the left. If the [<--] key is pressed as many times as there are characters in the buffer, the cursor will continue to move left, and remove old characters from the screen and buffer until it is back at the original starting location. Additional [<--] entries will do nothing. Backspacing up the record Pressing the [Esc] key twice will move the input sequence back two items and so on. When the blinker is at the first item (the Primary description), an [Esc] entry will produce the original entry prompt which will allow exit from the record without save. The option to go back into the record will also be available by pressing the <CR>. Previous data preserved by PCAT All of the data items that had been entered up to the point where the [Esc] key was first pressed will be preserved. The blinker can be moved back down the record with multiple <CR>'s. This way data values need not be re-entered just because the blinker is passing by. You should think of the [Esc] key as the [ ] and the <CR> as the [v]. This concept required a few extra lines of code, but we thought it was worth all those saved keystrokes. (Think how much longer your keyboard will last because of our forethought...what a deal). A SINGLE CORE RECORD The following is a brief description of the data items that make up a single core record. Primary Description The first item in a core record is the primary description of the core. This is any 32 characters that you feel will do the job. This description will be used by LAMCON when prompting you for core selections. If you want to include a density designation, it is suggested that you define this first (ie., 75 ACMEcell rather than ACMEcell 75) The reason for this is that LAMCON will use only a leading portion of the description in order to maximize the screen display. If more than 32 characters are input, only the first 32 will be used. No error or warning will be issued by PCAT that the string was truncated. Secondary Description This is another text line of 32 characters which was originally intended for the name of the manufacturer but what it is actually used for is up to you. Consider it an extra line to hold whatever data you consider worth holding. An example of what might go here is the type of core material. eg. PVC, PU, BALSA... Density This value is to represent the density of the core material in units as specified with the keyword UNITS. The required units will be displayed in the right hand window of PCAT. Compression Values The first of the mechanical units in the record is compression. Strength is entered first, then modulus. The entries are converted to a scientific format so that they fit evenly on the screen. These values are usually very easy to obtain from core manufacturers because testing is quick and easy. Shear Values The second of the mechanical units in the record is shear. Strength is entered first, then modulus. These values are also very easy to obtain from core manufacturers but the problem then becomes accuracy. Because the value of a core is sometimes based on it's shear data, the advertised values may be on the high side. To be on the safe side, get a few opinions and develop an average. Tension Values The last of the mechanical units in the record is tension. These values are not vitally important because the core material is usually not put into direct tension. Poisson Ratio Not much can be said here except that this is a real value. C2BASE Costfile This is one of the interesting features of the COPAN/II system. When this package was designed, it was realized by the authors that cost analysis is equally important as strength and stiffness calculations. Due to this realization, it is possible to catalog all core costs using the module C2BASE. This program sets up another text file which holds all costs for a specific file or manufacturer. Using C2BASE, you build a type of spreadsheet for all densities and thicknesses. Then, when it's time to analyze costs, it is not necessary to have a current price sheet available. This is a really nice option for those persons using COPAN/II on the portable/lap machines. If you do not wish to use this feature, there is no need for alarm. Simply press the <CR> and PCAT will place a flag in the file which means you elected to not use this option. If you do wish to use it, enter a filename that you will use later to hold cost data. For example, for a Klegecell core, you might use the name KCELL. For Divinycell- DCELL and so on. Additional Text 1 Whatever additional information you wish to store with the record is held in the last two data items. The limitation is 32 characters. If you use more than 32, PCAT will ignore them. Additional Text 2 Same applies here as above. Rather than duplicate the text, please rotate your eyeballs a few degrees up and read again. Thanks. SAVING CORE RECORDS When the last data item has been entered into the record, a message will be displayed in window 2 which indicates the current options. Here it is possible to do one of three things: Options Key ---------- ----------- Save it [S] Change it [Esc] Abandon it [SPACE BAR] Save [S] When a record is saved while in the create mode, it is merely appended to the existing datafile. If one does not exist, then one is created and the record then becomes the first in the file. To record the information, a single press of the [S] key will write the data to disk. The name of the file written and where it was written will be displayed. When the save sequence is complete, the entry prompt will be displayed in the command window. In addition, all of the information which was on the screen is removed, which gives the appearance of a fresh record waiting for new data. At this point a <CR> will begin the data entry sequence again while the [Esc] key terminates CREATE and returns control to the Main> prompt. Change [Esc] If a bad character or value is detected before the [S] key is pressed, it can be changed by backspacing up the record using the [Esc] key. Each press of this key causes the blinker to move one field up the record. When the blinker points to the data item which requires change, key in the new value or string and enter it with a <CR>. The corrected value or character string will be displayed over the old one. Make all changes this way using the [Esc] key to move up the record and the <CR> to move down. When the changes are complete, keep pressing the <CR> until the blinker moves beyond the last data item. Don't worry about entering too many <CR>'s, when you reach the bottom of the record, as additional <CR>'s have no effect. When the end of the record is reached, these three options are again presented. Abandon [SPACE BAR] If for some reason you do not wish to save the record on disk, it is possible to bypass the disk writing procedure by pressing the [SPACE BAR] once. Usually if the time is spent to enter the record, it would make sense to save it. However, it is possible that you may have just finished entering a Klegecell core with a DIAB.MAT filename waiting in the wings. Rather than write a record to the wrong file, the [SPACE BAR] can come to the rescue. EDITING CORE RECORDS To edit a core record, the keyword CORE is entered at the Main>. Upon doing so, a prompt will appear to determine whether you wish to create or edit a core record. As before, the first letters of Create and Edit will be highlighted in bright white. This time, the [E] key is used. After [E] has been pressed, the command window will produce a prompt for the record that should be retrieved from disk. A small message will also be displayed in the data window reminding you that you must know which record number you wish to edit. Scanning For Records Should you forget which record is which, a scan function is available from the Record #> By entering the letter [S] a scan of all records will be produced on the screen. What is a scan? A scan consists of the record # and its primary description. The record data will be output to the screen without pause so if the file contains more than a screenful, it will be necessary to execute a keyboard interrupt using the [Ctrl] [S]. By pressing [Ctrl] and then [S] you will cause output to stop. To resume the action, press the [S] key again. If you need to stop it again, repeat this keyboard sequence. If you are not fast enough, just do another scan by entering the [S] again when the Record #> prompt returns. When the record # is determined, enter it at the Record #> prompt and don't forget the <CR>. After a slight delay for disk access, the data screen will be replaced with what looks like a new record without data. Actually, that's not the case. All of the data has been read into the memory but they haven't yet been put on the screen. Looking at the existing values... To view them, press the <CR>. Each <CR> will produce one value. The blinker will show where the next value or string will be placed. If it is known exactly which data item requires edit, the <CR> should be pressed until the blinker is pointing to it. By typing in the new value and ending with a <CR>, the new value is placed on the screen. If too many <CR>'s are entered, the blinker can be moved backward using the [Esc] key. If this sounds familiar, it's because this is the same routine that was used for CREATE. Except with CREATE, the sequence begins with all strings set to null and all values = 0. Here, the variables are first filled with the record data which was read from disk. At the completion of the edit, press the <CR> until the blinker moves beyond the last data item. This will bring back those same three options which allow you to: Save - Change - Abandon For the Change and Abandon, the same explanations apply as did for the CREATE. If you're unsure about these you might want to flip back a few pages and refresh your memory. The Save is the same in terms of use. That is, all you do is extend one finger and apply a few ounces of pressure on the [S] key. PCAT does the rest. What you will then see on the screen is what filename was used and where it was written. This information is just to keep you informed of where your data was moved to and to confirm that it is where you intended. PCAT does some housecleaning... After the primary save is complete, PCAT takes care of a few other details which, for the most part, remain fairly transparent to the user. The only exception to this transparency is that your edited record now exists at the end of the file even if it was the first one when you began. Because of the nature of sequential files, it is necessary to write the entire file even if only a single record is being changed. Rather than read the entire file into RAM, PCAT reads only one record at a time and stops after it has read the requested record #. If for example, record #5 in a file of 15, requires edit, the first five files must be read before the edit may begin. When the edit is complete, the correct data must now be inserted back into the file. However, because the entire file was not read it is not possible to write this corrected record back into its original location. One too many records... So what PCAT does is write the edited record at the end of the file. But now a problem arises, because two records with the same general information exist with the exception that one is correct and one is not. PCAT must now restack the file to remove the old record so that the total number of records is equal to the pre-edit level. The .UNM file The first action is to rename the appended file as filename.UNM. The .UNM is the file extension which indicates UNModified. The UNM file will continue to grow with every edit. This way a historical file is maintained which can be used if an old value needs to be reinstated. PCAT does not use .unm files so if you wish, you may delete it. After the appended file has been renamed with the .UNM extension a new file is written which uses the current core filename. Before the rewrite begins, a flag is set to the number of the most recently edited record. The new file is then created using data from the .UNM file. When the record number in the new file equals the flag, the write operation pauses while input from the .UNM file continues. This effectively skips over the edited record in the .UNM file and continues for the remainder. The result is that the edited record moves from its original position to the end of the file. COREDATA.MAT COREDATA.UNM COREDATA.MAT A A A B B Restacked C C Becomes C to ----> D D -----> D B' B' B' This process should not present a problem unless you had your heart set on memorizing where each record was in the file. Even this is not a problem as long as you don't edit your materials. What happens then? When the edited SAVE is complete, the Record #> prompt will be redisplayed in the command window assuming that another record will be modified. By entering a valid record #, the entire process begins again. If the assumption is not correct, the Main> can be accessed by entering a null string. This complex task involves pressing the <CR> once. PCAT will respond with "Edit session terminated" and will wait for another key to be pressed. At that time, the screens will clear and PCAT will be ready for the next Main> Keyword. CREATING PLY RECORDS Creating a ply record is just as easy as it was with the core. The functions and operation of the two procedures are nearly identical because the only difference between the two was the actual data being collected and written to disk. Basically, if you've already created a CORE record, you shouldn't have to read this section. The keyword PLY To create a ply record, the keyword PLY is entered at the Main>. Upon doing so, a prompt will appear to determine whether you wish to create or edit a ply record. Turn back a few pages now if you need additional guidance. The core create/edit sequence is identical. ---------------------------------------------------- Ply Description:>> Secondary Text : Resin % by Wgt : STRENGTH MODULUS 0 90 0 90 Tens. Comp. Shear Data Type : STRING Poissons Ratio: Therm.Exp: Max.Length: 32 Laminated Ply Thickness: Dry Fabric Cost: Dry Fabric Weight: Text 1: Text 2: ---------------------------------------------------- Ply Creation ( 1) >> ---------------------------------------------------- The PLY Create Screen Primary Description The first item in a PLYDATA record is the primary description of the ply. This is any 32 characters that you feel will do the job. Please do not include any commas in the description as it will be construed as a delimiter, which will really screw things up. This description will be used by the laminate construction program when prompting you for ply selections. If you want to include a weight or style designation, it is suggested that you define this first (ie., 24 Woven Roving rather than Woven Roving 24) This is because the laminate construction program will use only a leading portion of the description in order to maximize the screen display. Not to worry, however because the full description can be invoked but this will require a few additional keystrokes. If more than 32 characters are input, only the first 32 will be used. No error or warning will be issued by PCAT that the string was truncated. Secondary Description This is another text line of 32 characters which was originally intended for the name of the manufacturer, but what it is actually used for is up to you. An example here would be a note regarding resin matrix used. Resin Content (percentage) This represents the percent of resin by weight that the laminate contains. This is used by the cost and weight analysis program COSAN for calculations. This entry does not affect the mechanical properties of the laminate. The variable is declared as real so a 45.1 would be acceptable. Tensile Values Four real values are required to be input here. Should you not have all the properties a null string will produce zero. It is suggested that if you are unable to obtain these values from the material distributor, contact the manufacturer. If this is not possible, then estimate a value. Note: These are laid-up values! When the value is entered, it is converted to scientific notation so that it fits on the screen. The original precision is saved on disk.