Bicycle wheel flop -- the drop laboratory
=========================================
VERY PRELIMINARY DRAFT (October 2026).  This packet has been designed but
not yet run with students; the numbers in it are predictions.  The author
would appreciate feedback from anyone who tries it or finds an error.

  Nick Tufillaro, Aqualytics, Corvallis, Oregon
  nick@aqualytics.eco      http://www.aquahue.net

Contents
--------
flop_drop_lab.pdf        The laboratory packet (18 pp): Part I theory and
                         assumptions, Part II instructions, two data sheets.
flop_drop_lab.tex        Its LaTeX source.  Build: pdflatex three times.
flopcommon.tex           Shared preamble and TikZ macros (needed to build).
figures/fig_geometry.pdf The front-end geometry figure (Fig. 3 of the paper).
fit_drop.m               MATLAB/Octave function that does the analysis of
                         Sec. 12: lever correction, small-angle slope, fit of
                         the exact drop law with the offset floating.

protractors/
  flop_protractor_head.pdf/.tex  The steer-angle protractor the packet uses:
                         a disc for the top of the head tube, one US-letter
                         sheet, print at 100 %.  Reads delta in the plane
                         perpendicular to the steer axis.
  flop_protractor.pdf/.tex       The earlier floor protractor (six letter
                         tiles), kept as the alternative discussed in the
                         packet's steer-angle section; a reading on the floor
                         needs the conversion given there.

slides/flop_demo_talk.pdf  Slides for the demonstration talk (AAPT, Corvallis,
                         17 October 2026).

in_development/          Two further measurements (steering torque with a
                         spring scale; the runaway of released bars) written
                         up as laboratories in development.  They predate the
                         notation change in the drop packet (they use the
                         axis tilt from vertical, lambda = 90 deg - alpha).

The packet accompanies the paper "Bicycle wheel flop" (N. Tufillaro,
submitted to Eur. J. Phys., 2026), which contains the derivations; the
bracketed equation numbers in the packet refer to it.  The paper is not
included here.
