Helpful Hints:

• As before, be extremely careful in what directory you store your work. Store it in the Handyboard directory while using the software.
• When you sit down to work with the program, copy it from the diskette onto the desktop of the computer. Pop the diskette out, and run the version on the desktop.
• Use SimpleText or TeachText to edit the programs. Be sure you have SAVED them before trying to load them in the Interactive C environment.
• It is easier to read the programs if SimpleText is displaying them in Courier font instead of the default. Print them out using Courier, as well.
• Keep a copy of working programs you write on your own diskette or in your network folder. Don't depend on retyping the code.
• If you are turning on a Handyboard and you want it to run the program which is currently loaded on it, just use the on/off switch.
• If you are turning on a Handyboard and you do not want it to run its current program, hold down the "Start" button while turning on the on/off switch.
• If you are taking over a Handyboard and software from another team, quit out of the Interactive C program and be sure to turn the Handyboard off. This will clear out the other team's programs and be sure that what you are running is your own creation.
• If you are changing from one program for the robot to another, make sure to "unload" the first program before trying to load the second.

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  1. Getting set up and started

  First, finish constructing your LegoBug properly, and construct a holder for the Handyboard itself to sit on top of your Bug.

  If you are ready to move on, collect from me a Handyboard, a diskette containing the software, a power converter, the board that connects the Handyboard to the computer, and both connector wires.

  If your group cannot access a Handyboard immediately, read through the handout on the Handyboard and Interactive C, the programming language for the robot. Look over the sample programs attached here and figure out what each one does by looking up the commands in the manual. Watch what other teams are doing.

  Do the following to get set to activate the robot:

  1. Plug the power adaptor into a plug on the floor.
  2. Plug the computer connector into the Modem port of your computer.
  3. Be sure that the off-robot board is plugged into the connector, and has a phone wire coming out the other side.
  4. Plug the other end of the power adaptor into the off-robot board, making sure that the switch on the board is in the "Normal," not "Zap" position.
  5. Copy the software from the diskette onto the desktop of the computer by holding down the Option key and dragging the folder onto the desktop. If you don't hold down the Option key, it will move the folder instead of copying it.
  6. Place the Handyboard on your robot and make sure it is secure.
  7. Plug the left motor of your robot into the second motor slot from the left, and plug the right motor of your robot into the rightmost slot.
  8. Plug the left touch sensor wire into the rightmost "digital" connector (see diagram in the manual) and plug the right touch sensor into the next connector.
  9. Plug the phone wire into the jack on the Handyboard.
  Now everything should be connected together, no loose wires. Turn on the Handyboard, holding down the "Start" button on it at the same time. You should see a little beating heart on the LCD panel. Start up the Interactive C application by double-clicking on the "IC HB 2.853 Modem" icon. This is an "Interactive" programming language: you can type commands and they will be immediately executed on the robot. You can also create whole programs to be executed on the robot.

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  2. Using the robot interactively

  Look up the commands in the manual for controlling the motors. Try the following commands one at a time (typing exactly what I put below), and note what happens:

  beep();
  fd(0);
  off(0);
  fd(1);
  ao();
  fd(2);
  ao();
  fd(3);
  ao();
  bk(1);
  bk(3);
  ao();
  motor(1, 50);
  motor(3, -50);
  

  Make the robot spin in place without dragging either drive wheel.

  At this point, please let another group work with the Handyboard if one is waiting. Look over the programs below if you have not done so already.

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  3. Beeping when touched

  Using SimpleText, open the file beeper.c which should be in the same directory as the IC program. You should have a printout of this program attached to this project. Look over the program. Hide SimpleText (using icon in the upper right corner of the menubar).

  In Interactive C, type load beeper.c at the prompt. It should load the file without errors, and automatically download it to the robot.

  To execute the program, turn the Handyboard off, and then on again. This program should beep every time you press the "Start" button. Notice that the message on the LCD panel changes, too.

  Go back into SimpleText. Edit the file beeper.c so that instead of looking for the start button to be pressed, it looks for the touch sensors to be pressed. Use the procedure defined at the top of the file: touched or both-touched. To call touched you put an expression like:

  touched(leftTouch)
  

  If it is called by itself it needs a semi-colon at the end, but if it is being used in an if statement or as the test condition for a loop (for or while) then it does not need a semi-colon at the end.

  Save the new file under the name beeper2.c so that you still have the original.

  Go back to Interactive C, and unload beeper.c. Then load beeper2.c. You may need to "debug" your new program, but keep working until you get it to do what you want.

  Finally, make the program print out a different message when the left sensor is touched than when the right sensor is touched.

  At this point, let another team use the Handyboard and software. Save all your work, and copy it to your own diskette or network folder. Then remove the copies that you created in the folder on the desktop so the next team has a clean slate to work from. DO NOT ERASE THE FILES THAT I PUT THERE!

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  Moving purposefully

  Open the file moving.c in SimpleText and look it over. This program causes the robot to move straight ahead for a fixed amount of time, then to turn for a fixed amount of time, and then to move ahead again.

  Load the file in Interactive C (be sure to unload any existing files first). Now, turn the Handyboard off and unhook the telephone cable from the robot. You might borrow a twist-tie or a rubber band to tie up the various wires so that they won't get tangled in the wheels. Setting the Handyboard on an open space (the floor in the hallway would be good) turn it on and watch the program run.

  Edit the file moving.c and save it as moving2.c so that the robot will trace out the shape of a square on the floor: it will move forward a distance, turn as close to 90 degrees as you can get, move forward again, and so forth.

  Load and test your program, being sure to unload moving.c before loading moving2.c.

  How would you have the robot move in a circle?

  Again, let another team have a try now.

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  Randomness

  Eventually we want the robot to wander randomly around its environment. The next program will get you started in the right direction. The program you'll create here will be the starting point for the final program of the project.

  Open the file berandom.c, and look it over. This program causes the robot to move forward a random amount every time the start button is pushed, and to turn a random amount every time the stop button is pushed.

  Load this file in Interactive C (did you remember to unload any previous files?), and take the robot back into the hallway to test out the program. Be sure you understand how it works.

  Now, edit the program, saving the new program as wander.c, so that the robot wanders continuously, moving forward, backward, turning left and right. Pick a time-scale between changes that makes the movement of the robot relatively graceful, and be sure that it is possible for the robot to turn completely around.

  Hint: You might use the random number procedure to pick among the robot's general options: move forward, move backward, turn right, turn left, and then do the chosen option for some random amount of time before repeating the process.

  If you want to get fancy, try adding procedures for arcing left and right (turning and moving at the same time). These would be just like the turning procedures, except that both motors would be moving in the same direction, just at different speeds.

  Test out your new program until it works satisfactorily.

  Now, let another team have access to the Handyboard and software.

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  Reacting to obstacles

  Now you're ready to combine a previous program with your current one. So far the robot will wander, but it ignores obstacles and just keeps going when it hits a wall. You wrote a program earlier that noticed when the left or right bumpers were hit: recall how to do that.

  Create a new version of the wander.c, wander2.c, so that in addition to what it did before it checks to see if one or the other bumper has been pressed. If it has, the robot should stop, beep a few times, and just sit there.

  You might let another team use the Handyboard here, too.

  Create your final program, wander3.c. This should, instead of stopping when a bumper is pressed, respond in a sensible manner: backing away from the obstacle, turning in a direction that will tend to reduce the likelihood of hitting the obstacle again, etc. Think about strategies for this before trying to write a program for it.

  The ultimate test for your final program is not the relatively open hallway, but the robot playpen I'll construct. You'll need to demo your final program before the rest of the class on Monday.