add second hole subsubsection and picture

picture illustrates how moving holes apart can minimize rotation

diff --git a/curriculum/arduino-to-deck/keep-holes-far-apart.svg b/curriculum/arduino-to-deck/keep-holes-far-apart.svg
new file mode 100644 (file)
index 0000000..0d90c54
--- /dev/null
+++ b/curriculum/arduino-to-deck/keep-holes-far-apart.svg
@@ -0,0 +1,379 @@
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+       style="font-size:20px;font-style:normal;font-variant:normal;font-weight:normal;font-stretch:normal;text-align:start;line-height:125%;letter-spacing:0px;word-spacing:0px;writing-mode:lr-tb;text-anchor:start;fill:#000000;fill-opacity:1;stroke:none;font-family:Linux Libertine Mono O;-inkscape-font-specification:Linux Libertine Mono O"
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+         sodipodi:role="line"
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+    <path
+       style="fill:none;stroke:#000000;stroke-width:1px;stroke-linecap:butt;stroke-linejoin:miter;stroke-opacity:1;marker-end:url(#Arrow1Send)"
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+    <path
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+    <text
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+       style="font-size:20px;font-style:normal;font-variant:normal;font-weight:normal;font-stretch:normal;text-align:start;line-height:125%;letter-spacing:0px;word-spacing:0px;writing-mode:lr-tb;text-anchor:start;fill:#000000;fill-opacity:1;stroke:none;font-family:Linux Libertine Mono O;-inkscape-font-specification:Linux Libertine Mono O"
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+    <path
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diff --git a/curriculum/challenge-bot.scm b/curriculum/challenge-bot.scm
index 32b3020dfa4121be5eff3acc975b8cd0b9df8396..29b24eb0d0e8d63caf8453943a3961aca9c24241 100644 (file)
--- a/curriculum/challenge-bot.scm
+++ b/curriculum/challenge-bot.scm
@@ -250,7 +250,20 @@
                  the deck.
                  it can translate and rotate freely.
                  with the first screw, the arduino can rotate around one
-                 point on the deck and can no longer translate much.])))
+                 point on the deck and can no longer translate much.])
+     (p [the second screw limits rotation a lot.
+             it also makes translation even more difficult.
+             it might even be too small to be detectable by directly
+             looking at it.])
+     (p [to choose where the second hole and screw should go, we should
+            keep in mind that the goal is to attach the deck to the
+            arduino.
+            this means minimizing rotation and translation.
+            the picture below shows that the second hole should be as
+            far as possible from the first hole, since that minimizes
+            rotation.]
+        (figure :legend "arduino to deck / keep holes far apart"
+                (image :file "arduino-to-deck/keep-holes-far-apart.png")))))
    (subsection
     :title [third and fourth hole and screw]))
   (section

diff --git a/curriculum/makefile b/curriculum/makefile
index 8ef3a0fb402aaf807efaf5cd6476e31c2ead6299..08764ae3b68bb84e7413f65f8356cbe113ab3297 100644 (file)
--- a/curriculum/makefile
+++ b/curriculum/makefile
@@ -80,6 +80,7 @@ challenge-bot.html: challenge-bot.scm \
                arduino-to-deck/screw-cross-section.png \
                arduino-to-deck/6-32-screw.png \
                arduino-to-deck/4-place-arduino-closeup.png \
+               arduino-to-deck/keep-holes-far-apart.png \
                makefile
        @skribilo $< > $@