














                                       ATTENTION

            This version of KIDware's SCIENCE FAIR disk is distributed as
            'careware,' shareware with a heart.  If you use this disk, we
            encourage you to register it using the form at the end of this
            document or the form in file REGISTER.  Registration cost is
            just $11.95.  With registration, you will receive a new disk
            with two new programs.  One-half of your registration fee ($6)
            will be donated to St. Jude Children's Research Hospital in
            Memphis, Tennessee.  This hospital specializes in helping
            children diagnosed with cancer.  A statement of our donation
            record is available upon request.

            This document describes the version of SCIENCE FAIR you receive
            upon registration.  The registered version has six programs,
            not the four included with the careware version.  The two
            programs in the registered version not included with the
            careware version are ROBOT ARM and PENDULUM.

            We hope you enjoy evaluating SCIENCE FAIR for your use.  We
            encourage you to register it for the sake of continued software
            development efforts on the part of KIDware and for the sake of
            the many children with cancer helped by St. Jude's.


                                        KIDware
                                1380 156th NE, Suite H2
                                  Bellevue, WA 98007
                                    (206) 721-2556









































                                   User's Guide For


                                     SCIENCE FAIR

                                      ISD/ITD163
                                     Version 3.01






                                        KIDware
                                1380 156th NE, Suite H2
                                  Bellevue, WA 98007
                                    (206) 721-2556


















                                   (c) KIDware, 1992
                                  All Rights Reserved





                              Page 1 - (c) KIDware, 1992











                                   User's Guide for


                                     SCIENCE FAIR






                                     INTRODUCTION


            SCIENCE FAIR features six programs that demonstrate the
            application of mathematical and scientific principles to the
            simulation of actual physical processes and systems.  We
            believe, with proper guidance and appropriate instruction, the
            programs can be used by children from the early primary grades
            through high school.  CIRCUITS allows study of simple
            electrical circuits using lights, batteries, and switches.
            LEVERS provides instruction about basic lever types and
            required balancing forces.  ROBOT ARM demonstrates basic
            robotic motion problems.  MOON LANDER teaches about speed and
            acceleration as you try to land your vehicle on the moon.
            PENDULUM simulates the motion of a simple pendulum.  WATER
            WHEEL is a fun introduction to the world of chaos in
            mathematics.



                   COMPUTER REQUIREMENTS AND INSTALLATION PROCEDURE

            To use SCIENCE FAIR, you need an IBM compatible computer with
            at least 256K of memory, a floppy disk drive, DOS 2.0 (or
            higher), and graphics capability (Hercules monochrome, CGA
            color, EGA color, or higher).  A mouse is optional.  If you use
            floppy disk drives, the disk is ready to use as is.  But before
            using the programs, we suggest you do two things:  make a
            backup copy of the disk and then set up the disk to your
            particular system.  If you use a hard disk drive, install the
            disk on your hard drive and then do the suggested setup.
            Depending on the number and types of disk drives you have,
            follow the given instructions.


            Single Floppy Drive System:

            1.   Place DOS disk in drive A and start system.  Have
                 formatted blank disk ready for use.
            2.   Replace DOS disk with SCIENCE FAIR disk and type:
                 COPY A:*.* B:   This will allow you to copy the files



                              Page 2 - (c) KIDware, 1992











                 from the SCIENCE FAIR disk (referred to by DOS as
                 disk A) to your blank disk (referred to by DOS as
                 disk B).  Follow instructions given by computer.
            3.   The backup procedure is now complete.  Put the
                 original copy of the SCIENCE FAIR disk in a safe
                 place; you will always use your copy.  Now, place
                 that copy in drive A and proceed to setup
                 instructions.

            Dual Floppy Drive System:

            1.   Place DOS disk in drive A and blank formatted disk in
                 drive B; start system.
            2.   Replace DOS disk with SCIENCE FAIR disk and type:
                 COPY A:*.* B:   This will allow you to copy the files
                 from the SCIENCE FAIR disk to your blank disk.
            3.   The backup procedure is now complete.  Put the
                 original copy of the SCIENCE FAIR disk in a safe
                 place; you will always use your copy.  Now, place
                 that copy in drive A (or B) and proceed to setup
                 instructions.

            Hard Disk System:

            1.   Start system.
            2.   You first need to create a directory for the
                 programs.  At C: prompt, type MD C:\SF   This creates
                 a directory name SF on your hard disk (you may use
                 another name if you want).  Now, move to that
                 directory by typing CD C:\SF
            3.   Place the SCIENCE FAIR disk in drive A.  Type:  COPY
                 A:*.* C:   This will allow you to copy the files from
                 the SCIENCE FAIR disk to your hard disk.
            4.   Installation is now complete.  Put the original copy
                 of the SCIENCE FAIR disk in a safe place.  Proceed to
                 setup instructions.


















                              Page 3 - (c) KIDware, 1992











                                  SETUP INSTRUCTIONS

            To set up the disk for your system, place your copy of the
            program disk in a drive (or go to directory C:\SF on a hard
            disk) and type:  SETUP   You will be asked five questions;
            answer accordingly.  The setup routine will write two files to
            your disk, so if using a floppy disk, make sure it is not
            write-protected.

            The first question asks what type of graphics system you have:
            Hercules monochrome (HGC), CGA (Color Graphics Adapter) or EGA
            (Enhanced Graphics Adapter).  Choose the proper response
            (either use the cursor key to move the highlighting and press
            <Enter> when the desired response is highlighted or press H for
            Hercules, C for CGA, E for EGA).  Initially, the computer will
            highlight the graphics system it believes you are using.  If
            you have VGA graphics, choose EGA as your response.  If you use
            Hercules monochrome graphics, all text screens will appear half
            width, graphics screens may be slightly compressed, and of
            course no color will appear.  This is normal.  If any screen is
            scrambled, you have to adjust your monitor's vertical and/or
            horizontal hold controls.  Unfortunately, the Hercules graphics
            driver may not work with all computer/monitor systems.

            The second question asks if you have a mouse installed.  If you
            have a mouse, answer 'Yes'; if not, answer 'No'.  If you use a
            mouse, a utility will be loaded that allows your mouse to
            perform the cursor key movements and two other keystrokes
            described in the program running instructions.  For your
            reference, the mouse will perform the following:

                           Move Mouse Up - Cursor Up
                           Move Mouse Down - Cursor Down
                           Move Mouse Left - Cursor Left
                           Move Mouse Right - Cursor Right
                           Press Left Mouse Key - <Enter>
                           Press Right Mouse Key - <Esc>

            So, whenever the running instructions call for cursor key
            movements, or use of the <Enter> or <Esc> keys, you may use
            your mouse instead.  Also, in order to use the mouse, a mouse
            software driver must be loaded prior to using the SCIENCE FAIR
            disk.  This driver is usually called MOUSE.COM and is almost
            always loaded when your computer boots up, hence you probably
            don't have to make any changes.  If, however, no driver is
            loaded when your machine boots up, you have to load it
            yourself.  Refer to your mouse's manual for instructions.

            The third setup question asks if you want sound.  In most
            cases, you should answer 'Yes' since almost all of the programs
            use sounds to indicate correct/incorrect responses.  If



                              Page 4 - (c) KIDware, 1992











            however, for instance in a classroom situation, you find the
            sound disturbing, then answer 'No'.  If you turn the sound off,
            there will be slight delays in the programs where sounds would
            usually be heard.  You may also hear some low-volume clicking
            sounds.

            Some of the programs use actual physical dimensions and
            measurements to allow you to build replicas, if desired.  This
            information can either be in metric units (centimeters, meters,
            kilograms) or US (English) units (inches, feet, pounds).  The
            fourth question asks if you want metric units.  If so, choose
            Yes.  If not, that is you want to use US units, answer No.

            The last question involves highlight color.  In all menu
            selections, there will be one key highlighted in some color.
            One way to select the corresponding menu item is to press that
            highlighted key.  Because different graphics system have
            different contrast and color characteristics, the default
            highlight color (bright yellow) may not be acceptable.  Use the
            up/down cursor keys to change the highlight color until it is
            acceptable to you, then press <Enter>.

































                              Page 5 - (c) KIDware, 1992











                             PROGRAM RUNNING INSTRUCTIONS

            Once the programs are installed and set up, you can run them.
            Please note if you ever change your system setup (different
            graphics system or add/delete mouse), you should rerun the
            setup program.  Running the programs is simple.  If you are
            using floppy drives, place your copy of the program disk in a
            drive.  If using a hard disk, move to the proper directory by
            typing:  CD C:\SF   At the DOS prompt, type GO and press
            <Enter>.  After loading some needed files, a title screen will
            appear.  Press any key to clear the screen and a menu screen
            will appear.

            When the menu appears, choose the program you wish to run.  To
            make your menu selection here (and in all programs), you may
            use the cursor keys (or a mouse, if installed) or a letter key.
            To make the selection using the cursor keys, use the up/down
            keys until the desired selection is highlighted, then press
            <Enter>.  To use the letter keys, press the highlighted key in
            the desired menu selection.  To stop the programs, choose "Exit
            Menu Program."  Running instructions for each program are given
            below.

            One last comment:  the <Esc> key plays an important role in
            running the programs.  In any program, if you want to leave a
            particular menu screen, or any screen, pressing the <Esc> key
            will usually accomplish this.  Always try <Esc> if you seem to
            be stuck somewhere.


























                              Page 6 - (c) KIDware, 1992











                                        PREFACE

            The programs on this disk demonstrate a principle used
            extensively in engineering and mathematics disciplines, that of
            computer simulation.  Simulation is used to test designs and
            procedures before actually building some device or structure.
            For example, we use simulators to train airline pilots - this
            is much safer than training them in actual planes because if
            they make a mistake, there is no loss of airplane or life.
            Before constructing a building, we simulate it on a computer to
            see if it can withstand winds and possible earthquakes.  Using
            simulations, we can determine how a system operates, learn how
            its performance varies as we change different parameters, and
            develop operation procedures.

            Six simulations are covered:  basic electrical circuits, three
            types of levers, a two-dimensional robot arm, a landing lunar
            vehicle, a simple pendulum, and a special type of water wheel.
            We will look at how these simulations work (including how to
            use the corresponding programs) and how they could be used
            within a classroom or home learning situation.  In each
            simulation, we have attempted to use realistic numbers which
            would allow the more industrious of you to build the actual
            system and see how it compares to the computer model.






























                              Page 7 - (c) KIDware, 1992











                                       CIRCUITS

            In this program, you can build electrical circuits using
            batteries, switches, and lights.  By flipping switches and
            burning out light bulbs, you can see how the circuit you build
            works.  The program is run by selecting CIRCUITS from the menu
            screen.  Once in the program, you may either select "Circuit
            Simulation" to try some circuits, select "Program Description"
            for a brief explanation of the CIRCUITS program, or choose
            "Exit Program" to return to the program selection menu.

            In the program, the initial display shows the last saved
            circuit and gives you four choices:  Simulate Circuit, Edit
            Circuit, Clear Circuit (erases all circuit elements), or Return
            to Main Menu.  Make your choice.  First, let's look at what
            happens when you choose 'Edit Circuit.'  There are nine
            possible locations for circuit elements-you pick a desired
            location using the left and right cursor keys to move the box
            shown.  As the box is moved, the screen menu changes showing
            you your choices at that location.  If the space is empty, you
            may put in one of four elements:  a battery, a light, a switch,
            or a wire.  Use the up/down cursor keys to point to the desired
            choice, then press <Enter>.  Once an element is in place (or
            the chosen space is not empty), you make other choices.  If the
            space has a battery (a maximum of two batteries are allowed),
            you may either 'Flip' it (turn it around to change the voltage
            polarity) or 'Remove' it.  If the space has a light (a maximum
            of five are allowed), you may either 'Burn Out' (if it is OK)
            or 'Repair' (if it is Bad) or 'Remove' it.  If the space has a
            switch, you can 'Close' it if it's open, 'Open' it if closed,
            or 'Remove' it.  Lastly, if the space has a wire in it, your
            only choice is to 'Remove' it.  When the circuit looks like you
            want it to, press <Esc> to stop editing.  We suggest playing
            around with the circuit editor the first time you use the
            program to get used to its operation.

            Once your circuit is as desired and you choose 'Simulate
            Circuit,' the screen changes to the simulation screen.  Here,
            the circuit is redrawn with many different labels.  Five points
            are numbered at the top of the circuit - these are points where
            different voltages may be.  The values of these voltages (each
            battery is assumed to be a common 1.5 volt cell) are printed in
            the lower left hand corner of the screen.  All lights and
            switches are labeled with numbers and their status (lights-Bad
            or OK, switches-Open or Closed) is printed at the center of the
            bottom of the screen.  The program computes the currents
            throughout the circuit and the flowing paths are colored in
            purple - paths without current flow remain white.  If currents
            flow through OK lights, they light up.  At this point, you may
            make changes in the light/switch status and see the results.
            To make a change, use the cursor keys to point to the light or



                              Page 8 - (c) KIDware, 1992











            switch you want to change, then press <Enter>.  If you choose a
            light that is OK, it will burn out; if you choose a burned out
            light, it will be repaired.  If you choose an open switch, it
            will close; if you choose a closed switch, it will open.  After
            each change, new currents are computed and the circuit status
            is updated.  Please note that simulating the circuit involves
            some detailed math, hence each time something is changed a
            certain amount of time is needed to do the calculation.  While
            the program is calculating, the message 'Working ...' appears
            at the bottom of the screen.  When this message clears, the
            calculations are done.  To return to the edit screen, press the
            <Esc> key.

            Let's look at some ideas of how this program can be used.

                                    Basic Concepts

            An obvious use for the program is to study the basic concepts
            of current flow and voltages.  A great analogy to use is water
            flow in pipes, where pressure corresponds to voltage and flow
            corresponds to current.  Current (water) can only flow through
            complete paths.  The higher the voltage, the larger the
            current.  Read about resistance and how it affects voltage and
            current.  Study short circuits - if a wire is connected in
            parallel with a light, why does the current flow through the
            wire and not the light?  (Answer less resistance).  Learn about
            Ohm's law that says voltage = current times resistance - show
            why short circuits are dangerous (low resistance, high voltage
            means high current).

                                     Circuit Types

            There are two basic types of circuits:  series and parallel.
            First simulate a circuit with light bulbs in series.  See what
            happens when a light burns out.  Do the same for a parallel
            connection.  Explain the results.  Try simulating short
            circuits.  What's the difference between two batteries
            connected in series and two in parallel?

                                    Build Circuits

            Get some actual batteries, lights (flashlight bulbs work
            great), switches (use paper clips screwed to a block of wood),
            and wires.  Build some real circuits and play around with them.
            Study parallel and series circuits.  Get a voltmeter (try an
            electronics store) and measure voltages at different points in
            your circuit.  Try to get some concept of resistance - your
            voltmeter can be used to measure the resistance of different
            wires, lights, and other objects.  See what items are good
            conductors (low resistance) and which are not (high
            resistance).



                              Page 9 - (c) KIDware, 1992











                                        LEVERS

            With this program, you can study the three basic lever types
            and the balancing (lifting) forces required.  The program is
            run by selecting LEVERS from the menu screen.  Once in the
            program, you may select "Learn About Levers" for a brief
            tutorial on levers, select "Work With Levers" to try some
            levers, select "Program Description" for a brief explanation of
            the LEVERS program, or choose "Exit Program" to return to the
            program selection menu.

            If you choose "Learn About Levers," you will be taken through
            several screens of information defining basic terminology
            (fulcrum, effort, load), the idea of mechanical advantage, what
            effort is required to balance a known load, and examples of the
            three types of levers (1st, 2nd, 3rd class).  You press any key
            to move from screen to screen.  Press <Esc> to stop the review.

            If you choose "Work With Levers," the last saved lever
            configuration will be displayed, the current values for lever
            type, effort, load, and distances will be printed, and the
            options menu given.  You have six options:  Change Effort,
            Change Load, Move Effort, Move Load, Move Fulcrum, or Return to
            Menu.  Use the up/down cursor key to point to the desired
            option and press <Enter>.  We'll look at the 'Change Effort'
            option last.  If you choose 'Change Load,' use the up arrow key
            to increase the load value, the down arrow key to decrease the
            value.  The current value is printed in the lower left hand
            corner of the screen.  The load value may range from 0 to 50
            (no particular units).  When the value is as desired, press
            <Enter> to return to the options menu.  If you choose 'Move
            Effort,' use the left arrow key to move the effort indicator to
            the left, the right key to move it to the right.  When the
            effort is in the desired location, press <Enter> to return to
            the options menu.  If you choose 'Move Load,' use the left
            arrow key to move the load box to the left, the right key to
            move it to the right.  When the load is in the desired
            location, press <Enter> to return to the options menu.
            Likewise, if you choose 'Move Fulcrum,' use the left arrow key
            to move the fulcrum to the left, the right key to move it to
            the right.  When the fulcrum is in the desired location, press
            <Enter> to return to the options menu.  As the effort, load,
            and fulcrum are moved, their location (again, no particular
            units) values are updated on the screen.

            Once the lever configuration is as you desire, the simulation
            begins when you choose the 'Change Effort' option.  With this
            option, the effort is increased (to a maximum of 200) with the
            up arrow key and decreased (to a minimum of 0) with the down
            arrow key.  When the effort is near the value required for
            balance, the lever will begin to move.  If the effort equals



                              Page 10 - (c) KIDware, 1992











            the balance value, the lever will eventually level out.  Note
            that sometimes (since the effort can only be changed in
            increments of 1) that the exact balance value may not be
            attainable.  In this case, the lever may just oscillate about
            the level condition.

            Here are some ideas of what to do with the lever simulation.

                                    Basic Concepts

            Discuss the ideas of forces and moments (force times distance).
            Explain how moments cause turning actions.  Discuss the idea of
            mechanical advantage - and why sometimes a mechanical
            disadvantage is better.  How does friction in a lever come into
            play?  When is a lever without any effort or load balanced?
            Discuss how the weight of the lever itself could be added into
            the balance equation (as written in the program, the balance
            equation assumes a weightless lever).  Discuss the advantages
            and disadvantages of the three different lever classes.

                                  Identifying Levers

            See how many levers of each of the three classes you or your
            child can identify in everyday surroundings.  For each,
            describe what the load, effort, and fulcrum are.  Does each
            have a mechanical advantage or disadvantage or no advantage?

                                    Building Levers

            With a board, something for a fulcrum, and a few weights, it is
            quite easy to build your own lever system.  Build the different
            classes.  Measure forces using something like a spring scale.
            Examine balance conditions and mechanical advantage.





















                              Page 11 - (c) KIDware, 1992











                                      MOON LANDER

            You are the pilot of a lunar landing vehicle hovering over the
            moon.  You must land it safely using your thrusters.  The
            program is run by selecting MOON LANDER from the menu screen.
            In the program, you have several options:  Beginning Pilot,
            Novice Pilot, Junior Pilot, Intermediate Pilot, Senior Pilot,
            Advanced Pilot, or Change Gravity.  Choose one of these options
            or select "Program Description" for a brief explanation of the
            MOON LANDER program or choose "Exit Program" to return to the
            program selection menu.

            If you choose one of the pilot options, the simulation screen
            is drawn and the simulation begins.  On the screen are several
            important pieces of information.  The vehicle is drawn on the
            right side along with a side bar indicating direction of
            motion.  On the left are shown elapsed time, altitude, and
            speed.  Vehicle attitude (relative position to center and
            levelness), fuel level, and current thrust level are also
            shown.  The idea under each option is the same.  Your vehicle
            is some height above the surface of the moon at zero speed.
            Due to gravity, you begin to accelerate toward the surface with
            a corresponding change (goes negative) in your speed (a
            negative speed indicates descent - positive speed indicates
            ascent).  The current height and speed are always displayed.
            You slow your descent using the two available thrusters - the
            thrusters counteract gravity effects.  The left thruster is
            turned on/off with the left arrow key and the right thruster is
            controlled with the right arrow key.  The idea of the program
            is to be going at a slow descent speed by the time your
            altitude (height above the moon surface) reaches zero.  The
            thrust level may also be controlled (a range from 0 to 10).
            The up arrow key increases the available thrust, the down arrow
            key decreases this value.  At a level of 10, the thrusters
            provide a positive acceleration of 10 ft/s per second (3.0 m/s
            per second).  A safe landing is one where the final speed is
            between 0 ft/s and -10 ft/s (-3.0 m/s); higher descent speeds
            result in a crash!  To illustrate the use of these controls,
            let's go through a descent using the 'Beginning Pilot' option.
            We'll assume US units (ft) are being used and that gravity is
            set at 5 ft/s per second (the nominal value).

            Once 'Beginning Pilot' is selected, the height above the
            surface is displayed (somewhere between 2000 and 4000 feet) and
            descent begins.  As you descend, the altitude decreases and
            your speed toward the ground increases (at a rate of -5 ft/s
            per second due to gravity) until you apply the thrusters.  The
            screen is updated every second.  In the 'Beginning Pilot'
            option, both thrusters come on whenever the left or right arrow
            key is pressed.  Note that when you apply the thrusters, your
            descent speed begins to change at a rate of +5 ft/s per second



                              Page 12 - (c) KIDware, 1992











            (this is because the thrusters at maximum supply +10 ft/s per
            second up and gravity supplies 5 ft/s per sec down).  If you
            leave the thrusters on long enough, you can even begin to
            climb!  A suggested descent is to use the thrusters
            occasionally to keep your descent speed under -50 ft/s until
            you get to about 1000 feet altitude.  At 1000 feet, the lunar
            surface appears in the right side window.  At this point, try
            to adjust the speed to around -20 ft/s, then quickly adjust the
            thrust level (using the down arrow key) to 5 (at this level,
            the speed won't change since the thrusters exactly balance the
            gravitational acceleration).  From this point, leave the
            thrusters on and only change the thrust level.  Once you reach
            about 100 feet of altitude, increase thrust level (up arrow
            key) to 6 or 7 to slow down until the speed is under -10 ft/s,
            then quickly reduce the thrust level to 5.  Stay there until
            you are landed.  This example illustrates the basic program
            operation and one way to land.  There are many others - that's
            the idea of the program.  Learn about speed and acceleration
            and try any ideas you may have.  Also, each pilot option has
            different considerations things to consider.  Let's look at
            those.

            As shown above, the 'Beginning Pilot' option is the simplest.
            You only have to worry about final speed and both thrusters are
            controlled simultaneuosly.  The next option, 'Novice Pilot,' is
            the same, but with one more consideration.  At the Novice level
            and above, the fuel on board is displayed.  Each time you use
            the thrusters, fuel is used and the level drops (it drops more
            for higher thrust levels).  So now, you must land at a safe
            speed without running out of fuel.  At low fuel levels, a beep
            will be heard.  Once you run out of fuel, your vehicle will
            just accelerate toward the lunar surface, most likely resulting
            in a crash.

            The next level is 'Junior Pilot.'  This is the same as 'Novice
            Pilot,' except now the thrusters can be controlled
            individually.  Note if one thruster is on without the other,
            the vehicle begins to twist.  The amount of twist is indicated
            both in the vehicle graphic and on the attitude indicator on
            the left side of the screen.  You must land in a nearly level
            position.  Hence, now three landing limits must be met:  proper
            speed, fuel remaining, and nearly level.

            Next is 'Intermediate Pilot' which is the same as 'Junior
            Pilot,' except when the vehicle twists do to unbalanced
            thrusting, it also moves left or right.  Too much left or right
            movement results in a crash on the sides of the screen (you've
            move too far from your landing site).  This horizontal movement
            is shown both on the vehicle graphic and the attitude
            indicator.  Now, you must try to keep the speed under control,




                              Page 13 - (c) KIDware, 1992











            save fuel, keep the vehicle level, and keep the vehicle near
            the center of the screen window.

            It gets harder.  At the 'Senior Pilot' level, you must land
            within a lunar canyon that appears at an altitude of about 1400
            feet (427 meters).  This effectively narrows how far you may
            move in the horizontal direction.  Getting too close to the
            wall is disastrous.  And lastly, when you are an 'Advanced
            Pilot,' your thrusters work in a random-type manner.  When the
            thrusters are used at this level, the amount of thrust is not
            at all predictable.  Constant adjustments are needed to keep
            the vehicle centered, level, and within speed limits.  You'll
            probably find that, particularly at higher levels, it is much
            easier to run the program using the cursor keys than a mouse
            (if you have one).

            Try each level and see what it takes to master landing your
            vehicle.  The one last option to look at is 'Change Gravity.'
            The nominal gravitational acceleration is 5 ft/s per second
            (1.5 m/s per second).  This is about what the moon actually
            provides.  For more excitement, you can vary the gravitational
            acceleration by choosing the 'Change Gravity' option.  Use the
            up/down arrow keys to change the value.  It can range from 1 to
            9 ft/s per second (0.3 to 2.7 m/s per second).  Note this
            change does not affect thruster performance.  Lower amounts of
            gravity will result in much slower descents, but much easier
            control.  Large gravity values will result in very difficult to
            control landings.  Press <Enter> or <Esc> to return to the main
            menu.

            This program offers a lot of potential for further study and
            experimentation.

                                    Basic Concepts

            Much can be taught about just the concepts of speed,
            acceleration, and gravity.  Explain how the thrusters work to
            counteract gravity.  Explain how unbalanced thrust results in a
            twisting of the vehicle (the idea of moments).  Derive the
            basic equations that show the relations between altitude,
            speed, and acceleration.  Why is easier to land with low
            gravity?

                                  Landing Techniques

            It will become immediately obvious that there are many ways to
            obtain a safe landing with the vehicle.  Without a fuel
            constraint, you can take forever to land.  A more interesting
            problem is to try to land as fast as possible.  This is the so-
            called minimum time problem.  Or try to land using the least




                              Page 14 - (c) KIDware, 1992











            fuel possible - an important problem in space travel where you
            don't want to launch a lot of unnecessary weight.

            Another technique used in space travel is known as the coast
            and burn approach.  In this technique, you just let the vehicle
            drop until a certain time where you turn on the thrusters and
            leave them on (this approach has to be used because many
            vehicles don't have thrusters you can turn on and off).  So, in
            coast and burn, you have to try to figure out when to turn on
            the thrusters so by the time you reach zero altitude, your
            speed is within acceptable limits.  The more advanced of you
            can solve this as an algebra problem - try it.










































                              Page 15 - (c) KIDware, 1992











                                       ROBOT ARM

            The two-dimensional robot arm illustrates how robots are used
            to move things from one point to another.  It is also a lesson
            in trigonometry (for high school students).  The program is run
            by selecting ROBOT ARM from the menu screen.  Once in the
            program, you may either select "Robot Arm Simulation" to use
            the robot arm, select "Change Parameters" to adjust the
            simulation to desired values, select "Program Description" for
            a brief explanation of the ROBOT ARM program, or choose "Exit
            Program" to return to the program selection menu.  We will look
            at what parameters can be changed after briefly describing how
            to use the simulation.

            In the program, the initial display shows the robot arm in its
            current configuration.  The arm consists of two links, each of
            adjustable length (L1 and L2).  The first link can pivot about
            the center of the displayed grid, while the second link can
            pivot about the connection between the two links.  The two
            pivot points are drawn as circles.  The circle at the end of
            the second link indicates the current position of the robot
            arm.  To describe arm position, the robot arm is centered in an
            xy Cartesian coordinate system.  The angle the first link makes
            with the x axis is designated a, while the angle the second
            link makes with the first is designated b.  The robot arm is
            moved by changing these two angles.  The angle a is changed
            using the up arrow key (counterclockwise rotation) or down
            arrow key (clockwise rotation).  The angle b is changed using
            the left arrow key (counterclockwise rotation) or right arrow
            key (clockwise rotation).  As the angles change, their value
            (in degrees) is updated in the upper right corner of the
            screen.  Also printed on the screen are the corresponding x and
            y coordinates of the robot arm (the end of the second link).
            As the arm moves, small circles mark the trajectory followed.
            The screen is cleared of these circles by pressing the <Enter>
            key.  The simulation is ended by pressing <Esc> to return to
            the main menu.

            How this simulation can be used depends greatly on grade level.
            Again, I'll just list some ideas I have and you are free to
            choose/modify/add whatever you like.

                                     Etch a Sketch

            Primary school kids have found that its fun just to move the
            arm around the screen and see what kind of designs they can
            draw with the small circles.  This just makes the arm a
            computerized Etch a Sketch.






                              Page 16 - (c) KIDware, 1992











                               Coverage and Trajectories

            What points in the plane can or cannot be reached by the robot
            arm?  Describe the reachable area (it's a circle or an annulus
            if the two arm lengths are different).  Say you are at one
            point in the plane and need to get to another.  Can you get to
            the desired point?  If so, how many different paths can you
            take between the two points?  Is one path better than another?
            Why?  Once we select the desired path, how do we follow that
            path by varying a and b.  This is the basic robotics problem.
            Our arm (say the robot arm on the Space Shuttle) is at one
            position and we need to get somewhere else.  How do we get
            there considering possible obstacles, the fuel required to move
            the arm, and other constraints?  As an example, to go from
            x=10, y=0 to x=-10, y=0, we could just swing a through 180
            degrees in either direction.  But if there is an obstacle for
            y<0, we are forced to insure y is always greater than 0.  But
            such a swing is not the shortest distance.  Try to go from one
            point to another in a straight line by continuously adjusting a
            and b.  This is what robotics engineers do.  They compute
            tables of a and b variations that take their robot arm from one
            point to another.  There's a lot of potential for discussion
            about possible robot arm movements.

                         Resolution of Answer (Advanced Topic)

            Note that initially the robot arm angles can be changed only in
            increments of 5 degrees.  That means each angle can be set to
            just 360/5 or 52 possible positions.  With two angles, that
            means we can reach 52*52=2704 possible points in the Cartesian
            plane.  That is, we can't reach the infinite number of points
            within the plane.  Is this a problem?  It depends.  If we
            require a very accurate placement of the robot arm, we may need
            finer adjustments on the angle or a different control scheme,
            say having the capability to set angles within 1 degree.  This
            all just brings up the question (and a very important question
            in the real world) of how close does the answer have to be
            before it's considered correct.  Such discussions are relevant
            to almost every math/physics problem we ever solve.

                      Mathematics Behind the Arm (Advanced Topic)

            For students with trigonometry experience, or students with
            very good insight, see if they can write or describe the
            equations behind the robot arm.  Specifically, how do x and y
            values displayed related to the a and b values of the robot
            arm.  This could also bring up a discussion of choice of
            variables - are a and b the best way to describe arm motion.
            why are two variables required?  An even trickier question, and
            the difficult one for real-world application is:  given an x
            and y coordinate pair, compute the angles a and b that



                              Page 17 - (c) KIDware, 1992











            correspond to that pair.  For the mathematically inclined, this
            requires solving two nonlinear equations with multiple
            solutions!  An exercise left for the more ambitious reader.

            Before leaving the ROBOT ARM program, recall we can change some
            parameters by selecting the "Change Parameters" option from the
            main menu screen.  Three parameters may be changed:  the length
            of the two links and the resolution of the angle variation
            (discussed above).  To change a parameter, use the up/down
            cursor key until the value you want to change is highlighted in
            reverse type.  Make the desired changes.  Repeat this for each
            change.  Each parameter has limits.  The lengths can vary from
            1 to 9 (no particular units), with the restriction that their
            sum must not exceed 10 (if it does the computer will do some
            adjusting).  The angle resolution can vary from 1 to 45
            degrees.  Play around with the various values and see what you
            can come up with.





































                              Page 18 - (c) KIDware, 1992











                                       PENDULUM

            The next simulation is that of a simple pendulum.  The pendulum
            is displaced some amount from vertical and released.  Its
            corresponding motion can then be studied.  Such a system is a
            good introduction to the concepts of oscillation and frequency.
            This pendulum model assumes that the mass of the blob at the
            end of the pendulum is much greater than the mass of the
            connecting link and that there is some adjustable amount of
            friction in the pendulum pivot.  The program is run by
            selecting PENDULUM from the menu screen.  Once in the program,
            you may either simulate the pendulum (choose "Pendulum
            Simulation"), select "Program Description" for a brief
            explanation of the PENDULUM program, or choose "Exit Program"
            to return to the program selection menu.

            The pendulum simulation screen is divided into several regions.
            The first region simply shows the pendulum before it is
            released.  The lower left region shows the simulation
            parameters that can be varied and their values.  On the right
            of the screen are displays of pendulum motion described in the
            next paragraph.  Four parameters may be varied in the
            simulation:  initial angle, mass (of the blob at the end),
            length of the pendulum, and the amount of friction in the
            pivot.  To change a parameter, use the cursor keys until the
            arrow points to the item you want to change (Angle, Mass,
            Length, Friction), then press <Enter>.  An arrow will point to
            the parameter being changed.  Use the up or down arrow cursor
            control keys to change the value and press <Enter> when done.
            There are limits on what values can be used.  The angle can
            vary from 0 to 45 degrees, mass can vary from 10 to 5000 grams
            (0.1 to 10 pounts), length from 50 to 200 cm (10 to 80 inches),
            and friction from 0.00 to 1.00 (0 being no friction and 1.00 a
            large amount of friction).  Once the values are as desired,
            point to Go and press <Enter> to go.  At that point, pressing
            any key begins the simulation.

            During the simulation, the animated pendulum motion will be
            seen and in the upper right corner, a plot of the angle the
            pendulum makes with vertical (as time on the horizontal axis
            increases) is drawn.  In the lower right corner is a 'phase-
            plane' plot of pendulum motion.  On the horizontal axis is
            pendulum angle and on the vertical axis is the pendulum
            rotational speed.  The simulation runs for 20 seconds or until
            any key is pressed.  At the end of the simulation, the total
            time is printed.  You can rerun the simulation any number of
            times - press <Esc> to return to the main menu.

            So, what can you learn using such a simulation?  There are
            several things I can think of, depending on grade level.  I'll




                              Page 19 - (c) KIDware, 1992











            just throw my ideas out - use whatever you think might be
            useful.

                                  Pendulum Operation

            First, it is valuable just to have students describe how a
            pendulum works - what makes it oscillate, how does friction
            affect the motion?  It's all related to potential and kinetic
            energy and losses associated with the friction.  Will more
            friction slow it down or speed it up, why?  If the friction
            could be increased to infinity, what would happen?  How is
            motion affected by length?  mass?  initial angle?  How are the
            plots (angle response, phase plane) affected by different
            parameters?  Can students describe what's going on in the phase
            plane plot?  Where is speed highest?  Lowest?  Relate these
            answers to physical reality.  Can older students write down
            equations that help describe pendulum operation?  Where are
            pendulums, or similar oscillating devices, used?

                                 Oscillation Frequency

            For a given configuration (angle, mass, length, friction),
            compute the frequency of oscillation.  The frequency is equal
            to the number of cycles completed during the simulation divided
            by simulation time.  The unit of measurement equivalent to
            cycles per second is a Hertz, abbreviated Hz.

                                Frequency Dependencies

            For a given value of friction, how does the frequency vary with
            length and/or mass.  Plot the results of your experimentation.
            What if you need a certain frequency - how could you find out
            what length/mass combination gives you that value?  Use
            interpolation on your plot for such a computation.  How does
            frequency vary as the friction is changed?  Is frequency more
            dependent on length, mass, or friction?

                              Real Time vs. Computer Time

            The time printed on the screen is simulation seconds, or what
            we call real-time.  That is, it is the actual time it would
            take the pendulum to complete its motion if we were using the
            real system.  It is not the time required by the computer to
            compute its solution.  The time needed by the computer to
            compute its solution depends on how fast your computer is - for
            example, to compute 20.0 seconds of real time results requires
            just 3.2 seconds on my IBM-PC (80286 processor).  If you are
            using a 286 or faster processor, the program is purposely
            slowed down to make sure the computation time approximates real
            time.  If you are using an older machine, computation time will
            be greater than real-time.  In simulations of dynamic systems,



                              Page 20 - (c) KIDware, 1992











            we must distinguish between computer time and real-time.  This
            concept could be explained to students to initiate a discussion
            on simulation.  In most cases, the computer is fast enough that
            computer time is less than real-time, i.e. the computer can
            compute its solution faster than the real system.  In some
            cases, however, the simulation is so complicated that it might
            take a computer a couple of hours just to compute a few seconds
            of real-time results.  And there are cases where we want
            computer time to equal real-time, for example with airplane
            simulations.

                                  Building a Pendulum

            It might be fun to build a real pendulum and see how its
            performance relates to the simulated pendulum.  I would suggest
            just hanging a weight (mass value measured in grams) on a
            string (remember we assumed the weight of the blob is greater
            than the connecting link).  Using a stop watch, determine how
            long it takes to complete 10 complete (back and forth) cycles
            and compute the frequency of your pendulum.  Measure the length
            - it can't be longer than 200 centimeters (80 inches).  Enter
            the measured mass and length in the simulation with Friction=0
            and run the program.  See how that compares to your
            measurement.  Can you match the computed frequency with the
            computer by changing parameters?  (The length you need in the
            computer model may differ from the actual length - this is
            because we assume the connecting link of the pendulum has no
            mass.)  How can you estimate the amount of friction in your
            pendulum using the computer model?  How does the oscillation
            time vary as you change the length?  I'm sure you can think of
            more experiments of this type.  Using a real system to check on
            a computer simulation is called model validation.  It is
            probably the most important part of computer simulation - for
            example, it would be worthless to use airplane simulators to
            train pilots if they didn't accurately portray how an airplane
            works and responds.

                          Measuring Gravity (Advanced Topic)

            If you build a pendulum (of length L), you can use it to
            measure the earth's (or any other planet you could travel to)
            gravitational acceleration.  To do this, we first find the
            period of the pendulum - that's the time it takes to complete
            one oscillation cycle.  The best way to find the period is to
            displace your pendulum some amount and let it go.  Use a
            stopwatch to time how long it takes to go through 10 complete
            cycles.  Divide that time by 10 and you have an average period
            value - call that value T (in seconds).  Now you need the
            formula for gravity (G).  We'll just give it to you:

                 G = 4(3.14159)^2L/T^2



                              Page 21 - (c) KIDware, 1992












            This formula is read as 4 times Pi-squared times L divided by T
            squared.  G will come out in units of cm per second per second
            (metric units) or in per second per second (US units).  These
            are the units of acceleration (the rate of change of speed).
            As an example, say you have a pendulum that's 100 cm long.  It
            takes 20 seconds to complete 10 cycles, so its period is T=2
            seconds.  Then G is

                 G = 4(3.14159)^2(100)/(2)^2 = 987 cm/sec per sec

            Look up the actual acceleration in a reference and compare your
            value with the actual value.  Discuss possible error sources.
            You must be very exact in your timing of the period.  Also make
            sure the weight on the end of your pendulum is much heavier
            than the connecting link of the pendulum.  A good suggestion is
            to hang a heavy weight on the end of a long string.


                                   Inverted Pendulum

            Another type of pendulum we look at in the engineering world is
            an inverted, or upside down pendulum.  The mathematics involved
            in balancing an inverted pendulum are used in every rocket and
            missile guidance control system ever designed.  Have students
            describe how a pendulum would work if it were turned upside
            down (of course, the connecting link for an inverted pendulum
            could not be a piece of string!).  Make some inverted pendulums
            and try to balance them.  Can the students describe in some
            mathematical sense what logic they use in balancing the
            pendulum - this is what simulation specialists have to do in
            order to program a computer to do rocket guidance.  Are longer
            pendulums easier or harder to balance than shorter ones?  Hint:
            have you ever seen a short, fat rocket?




















                              Page 22 - (c) KIDware, 1992











                                      WATER WHEEL

            The final simulation studied is quite interesting.  In most
            systems, we can predict how they will perform given the
            operating parameters.  For example, we know if we displace the
            pendulum (in the PENDULUM program) from vertical and release
            it, it will oscillate and eventually stop (assuming some
            friction).  If we pull it back a little more, it will oscillate
            longer but still it will stop.  Would you be surprised if we
            pulled the pendulum back some more and it didn't oscillate, but
            instead swung completely around its pivot and rotated wildly?
            I think so.  Of course, we can't do this with the pendulum, but
            there are some dynamic systems where small parameter changes
            can result in very different, counterintuitive, overall
            behavior.  One classification applied to such systems is that
            of "chaotic system."  The water wheel examined here is a famous
            chaotic system known as Lorenz Water Wheel.  The program is run
            by selecting WATER WHEEL from the menu screen.  Once in the
            program, you may either select "Water Wheel Simulation" to use
            the wheel, select "Change Parameters" to adjust the simulation
            to desired values, select "Program Description" for a brief
            explanation of the WATER WHEEL program, or choose "Exit
            Program" to return to the program selection menu.  We will look
            at what parameters can be changed after briefly describing how
            the water wheel works and how to use the simulation.

            At this point, we suggest loading the program and going to the
            simulation screen for reference.  The water wheel is drawn on
            the left side of the screen.  Note the wheel consists of a long
            stick that rotates in a vertical plane about its center.  On
            the end of each stick are cans that can be filled with water.
            The weight of these cans cause the rotation of the stick.  A
            good mental picture of such a wheel would be a motorless ferris
            wheel with just two seats (one on each end of a stick).  The
            filling source is at the top of the wheel, so as the cans pass
            under the source they are filled with water.  Note the longer a
            can stays under the source, the more water it is filled with
            it.  The last piece of information needed is that each can has
            a hole in it, so the water is constantly draining and refills
            are needed to maintain some rotation.  So, in principle, the
            wheel works this way:  a can is filled which causes some
            rotation.  As it rotates, water is lost necessitating refill.
            As long as water remains in either or both cans, there is some
            motion.  The kind of motion imparted to the water wheel is
            where the chaos comes in.

            During the simulation, you only control one parameter - the
            value of the input flow source.  This is increased by using the
            up arrow or decreased using the down arrow key.  The current
            flow is printed (grams per second for metric units, ounces per
            second for US units) near the flow source, along with a bar



                              Page 23 - (c) KIDware, 1992











            chart indicating what proportion of the maximum flow is being
            used.  Several displays record the wheel motion.  In the upper
            right corner is a display of rotational speed.  Values above
            the line indicate a counterclockwise rotation, while values
            below the line show clockwise rotation.  The display
            immediately under this curve shows the vertical height of one
            of the cans.  And the final curve shows the level of the water
            in each of the two cans.  These curves will show the chaos
            implicit in the water wheel system.  Once the flow is set, the
            wheel will turn in one direction, change speed, rotate in
            another direction, and maybe even stop.  Completely different
            responses occur with different flow rates.  The simulation can
            be stopped and restarted by pressing the <Enter> key.  To leave
            the simulation screen, press the <Esc> key.

            Other parameters may be changed, in addition to the input flow.
            These changes are made by selecting "Change Parameters" from
            the main menu.  Several terms may be modified and each
            parameter has limits within which it may be set.  These
            parameters and their respective limits are:  stick length (L
            stick, 10 to 300 cm or 4 to 120 in), stick mass (M stick, 10 to
            2000 grams or 0.05 to 5 lb), can diameter (D can, 1 to 100 cm
            or 0.5 to 40 in), can height (H can, 1 to 100 cm or 0.5 to 40
            in), can mass (M can, 10 to 2000 grams or 0.05 to 5 lb),
            emptying time (T empty, 0.1 to 1000 seconds), filling time (T
            fill, 0.1 to 1000 seconds), and frictional factor (Friction,
            0.00 to 1.00, where 0 is no friction and 1 is maximum
            friction).  To change a parameter, use the up/down cursor key
            until the value you want to change is highlighted in reverse
            type.  Make the desired changes.  Repeat this for each change.
            If you want to permanently change the parameter set, press S to
            save the parameters you enter.  Press <Esc> when done changing
            parameters to return to the main menu.  Two parameters need a
            bit of explaining: the emptying time and filling time.  These
            are needed to establish the input flow maximum and the flow
            characteristics of the hole in each can.  The emptying time is
            the number of seconds it takes a full can of water to empty
            through the hole in the bottom.  The filling time is the time
            it takes to completely fill the can with the hole blocked and
            the input flow at maximum.  This time is used to compute the
            maximum possible input flow.  In the program, this maximum flow
            is divided into twenty segments - each press of the up arrow
            increases the flow into the cans by one such segment, hence
            once you have pressed the up arrow key 20 times, the flow is at
            maximum.  Likewise, pressing the down arrow key will reduce the
            flow by 1/20th of the maximum.

            With all this explanation out of the way, what do you do with
            the water wheel simulation?  Our suggestion is play with it and
            be amazed and astounded at its weird behavior.  Try all kinds
            of different physical parameters and flow rates.  Can you ever



                              Page 24 - (c) KIDware, 1992











            get the wheel to spin at a constant rate for a long period of
            time, like a water wheel is supposed to work?  Use the
            simulation to learn and study concepts like rotational inertia,
            friction, torques, and flows.  Can the advanced among you write
            equations that explain the wheel operation?  Build a water
            wheel - does the computer model match the real system.  I'm
            sure you can come up with lots of things to do with the water
            wheel.  For a good book on chaos, try "Chaos - Making a New
            Science," by James Gleick.  It was published by Penguin Books
            in 1987.












































                              Page 25 - (c) KIDware, 1992











                                    GENERAL COMMENT

            Many of the programs here use data files to record simulation
            information.  These files are read from and written to your
            program disk.  Thus, if you are using floppy disks to run the
            programs - do not write protect them.  If a program can't write
            a data file, it may suddenly stop.















































                              Page 26 - (c) KIDware, 1992











                                 WARRANTY INFORMATION

            The SCIENCE FAIR programs have been written with care, but
            there still may be bugs and problems.  If you find any such
            problems, please let us know.  We cannot guarantee the programs
            are completely error free.  We do guarantee they will load and
            run.  If, within one year of purchase, a program fails to load
            and run, simply return the original disk to us (postpaid) for a
            quick replacement.

            This warranty only applies to manufacturing defects.  No
            further guarantees are expressed or implied.  Also note that
            copying the disk (other than one backup copy) or this printed
            material is strictly prohibited by US and world copyright laws.
            For further information or help, contact us at:

                                        KIDware
                                1380 156th NE, Suite H2
                                  Bellevue, WA 98007
                                    (206) 721-2556


































                              Page 27 - (c) KIDware, 1992











                            SCIENCE FAIR REGISTRATION FORM

            If you use the 'careware' disk, SCIENCE FAIR, and like it, we
            ask that you register your copy.  This allows us to continue
            our program development efforts.  With registration, we will
            send you information about other KIDware programs, a new disk
            with two more programs (ROBOT ARM and PENDULUM), and one-half
            of your fee will be donated to St. Jude Children's Research
            Hospital in Memphis, Tennessee.  The hospital helps children
            diagnosed with cancer.

            Please register my copy of KIDware's SCIENCE FAIR disk.  The
            registration price is just $11.95 (WA residents, please add
            $0.98 sales tax).


            Name __________________________________________________________

            Address _______________________________________________________

            City __________________________ State _________ Zip ___________

            Disk Size:

            _______ 5.25 inch (360K)     _______ 3.5 inch (720K)

            Payment Method:

            _______ Check    _______ Money Order    _______ VISA/MasterCard

            Card Number _________________________________ Exp. Date _______

            Signature _____________________________________________________


            I obtained my copy of SCIENCE FAIR from

            _______________________________________________________________


            Send your registration to:

                                        KIDware
                                1380 156th NE, Suite H2
                                  Bellevue, WA 98007
                                    (206) 721-2556








                              Page 28 - (c) KIDware, 1992




