Note: The following activity uses MicroWorlds EX and MicroWorlds EX Robotics to create a simple collaborative turtle graphics and Logo programming activity that may be accomplished online or in a classroom. A more advanced quilting activity may be found here.
Old-Fashioned Logo Quilt-Making with MicroWorlds EX
©2006 Gary S. Stager
turtle graphics to create several geometric patches that may be combined with
those created by your peers in the construction of a digital quilt.
The most well-known, and perhaps powerful, aspect of Logo is
turtle graphics. The turtle has a pen in its middle and when it moves, with its
pen down, it drags the pen – resulting in a drawing. The intuitive nature
of drawing makes complex mathematical ideas concrete. Many books have been written
on the topic and few classrooms ever move beyond the drawing of simple
geometric figures. Turtle graphics is a powerful “microworld” for doing and
MicroWorlds EX features an
unlimited number of turtles. These turtles don’t just draw, they themselves can
wear costumes, be animated and interact with their environment. MicroWorlds EX
introduces a new data structure, the backpack. The backpack contains procedures
(programs), information about the turtle multimedia objects and instructions
for how to the turtle should interact with the environment. The turtle is in
short, the main actor in MicroWorlds EX.
This project will keep things
simple, unless you develop more sophistication, and focus on one turtle
drawing. There is lots of help available in the PDF manual and the help and
techniques built in the software. The following instructions are not intended
to be comprehensive. Use your community of practice and online materials to
fill-in the blanks. Some screens look slightly different between platforms.
Getting Started and Messing About
on Free Mode
a new turtle by clicking on the hatching turtle tool on the menubar and then on the page.
may move a turtle by clicking on it with the mouse and dragging it
elsewhere on the page.
may turn the turtle in rough increments by clicking on its nose and
dragging left or right.
with the following commands in the command center. Be sure to separate a command and its input
with a space. You may combine commands on one line if you separate them
with spaces before hitting enter/return.
bk, rt, lt are abbreviations
setc random 256
repeat number [list of instructions]
happens when you use large numbers?
do the various commands do?
may re-run a line in the command center or even edit it by scrolling onto
the line and then hitting return/enter.
your mouse over a command for a few seconds and the proper use of the
command will pop-up.
The Turtle’s Backpack
Every turtle has a backpack. It contains all sorts of
treasures. The turtle and the contents of its backpack may be exported and used
in multiple projects or even emailed to a friend.
the backpack of a turtle by either right-clicking (PC) or CTRL-clicking
(Mac) on the turtle.
The backpack should open. In it you should see six
different tabs. The default tab is state.
This tab provides information about the current state of the turtle. In this
activity, we will only use the state & procedures tabs.
It’s probably a good idea to name your turtle uniquely.
Otherwise, MicroWorlds EX will name turtles t1, t2, t3… etc.
your turtle by clicking on the Edit… button and inserting a new ONE
firstname/lastinitial, such as garys will do nicely for our purposes.
click on the Procedures tab at the bottom of the backpack window.
Procedures are the programs we write in MicroWorlds. A
procedure is a list of instructions with a name. Procedures may be comprised of
other procedures and the procedures built into MicroWorlds are called, primitives.
Procedures may be stored in the turtle’s backpack and then
are unique to that turtle or are kept in the project’s procedures tab. Project
procedures may be used by any object in the project. The project is what we
call the complete file in MicroWorlds – process and product.
It’s easy to create a procedure, but they don’t always work
as expected. That’s where the intellectually-rich process of debugging comes
Procedures always begin with the word to followed by the name of the procedure and end with
the word end. to & end need
to be on their own lines.
repeat 23 [fd 57 rt 106]
foo fd 75 foo
Foo is a procedure
and fooey is another procedure that
uses foo as a subprocedure. Simple Logo
procedures may be combined to create complexity. You might think of them as
building blocks or as verbs that do something when invoked.
Note: You edit
procedures by changing them. You cannot have more than one procedure with the
same name and you may not name a procedure with a word used already as a
Making a Quilt Patch
In order to create a communal quilt, we need to agree upon
dimensions. Let’s use the following procedure, frame, as the base for all of our patches. It creates a
black 100 X 100 square.
- Type frame in the command center and observe
the error message indicating that the word is not yet part of MicroWorlds’
vocabulary. That can be fixed!
the following procedure in the procedures tab of your turtle’s backpack.
repeat 4 [fd 100 rt 90]
- Close the turtle’s backpack.
- Type frame in the command center again and
see what it does. You should get a black square drawn on the page.
Your Assignment Should You Choose to Accept It
Once the frame is drawn, your job is to create colorful
creative designs within the frame.
Rules: The only rule
is that your turtle must return to its original position and heading at the end of the design.
the turtle graphics commands you learned earlier to draw a beautiful
design in the command center.
- If you
mess-up, type cg frame, and start
Once you are delighted with your creativity, it’s time to
teach the instructions to the turtle so they may be remembered and repeated.
You will do so by adding a new procedure to the turtle’s backback.
the procedures tab in the turtle’s
or above the frame procedure, hit return and type the following:
or retype your design instructions between frame and end.
- Type cg patch in the command center and see
if your quilt patch is drawn as expected.
there is a bug, think of a solution and change the procedure in the
You may also program the turtle to draw the patch
automatically when it is clicked on. To do so, follow these instructions:
the turtle’s backpack.
on the rules tab.
- Type patch in the OnClick field. Make sure that once is selected.
Make Additional Patches
and paste a duplicate turtle and change the patch procedure to create a
patch with a new design.
the instructions above to program the new quilt patch. All you need to do
is change the content of the patch procedure.
- Type patch in the command center to draw a
turtle’s patch, or click on it if you programmed the OnClick instruction.
- If you
have multiple turtles, you may speak to them by typing their name followed
by an immediate comma. Then any instruction that follows will be directed
to that turtle. For example:
Export Your Turtle(s)
a turtle and select export.
- Save your
- Share your turtle with your classmates.
Making a Quilt
several of your classmate’s turtles.
your MicroWorlds project.
each turtle via the File-Import-Import Turtle menu.
The Big Challenge!!!
As mentioned earlier, projects may have procedures, just
like turtles. Writing a quilt procedure in the procedures tab of the project can ask all of the turtles to
position themselves and draw their individual patch adjacent to others. Typing quilt in the command center would then draw
the entire quilt.
Repetition and symmetry are routine patterns in quilts.
you figure out a way to create a quilt made of communal patches and
triggered by one project procedure??