From the vaults, unedited:
THE ANATOMY OF A HIGH-TECH BICYCLE
by Steven K. Roberts
March 16, 1987
I received a number of questions about the various systems that make the
Winnebiko what it is, and this article is intended to provide a brief
technical overview of this complex machine.
Here, in no particular order, are the components of my electronic cottage on
wheels:
My main computer is the Hewlett-Packard Portable PLUS, an exquisite system with
896K of memory partitioned between system RAM and electronic disk. The
high-contrast amber LCD displays 25 lines of 80 characters, and a built-in 1200
baud modem makes the daily GEnie check-ins easy. But what really sells the
machine are the applications software packages baked into ROM: Microsoft WORD,
Lotus 1-2-3, dbase II, a "card-manager" filing system, communications software,
time manager, and a whole library of utilities. The net effect is a robust
bicycle business system that runs on rechargeable batteries and weighs 8 pounds
-- a system that has become so much a part of my daily reality that I'm
incapable of imagining nomadic life without it. It rides behind me, nestled in
foam along with a 3.5-inch disk drive, sometimes accepting charge current from
the bike's solar panels.
Computer number two, built into the control console, was once a Radio Shack
Model 100 -- upgraded to 256K and made truly useful through the addition of
Traveling Software's Ultimate ROM. But the machine is now hardly recognizable:
its keyboard and case are gone, and the display appears on the bike's front
panel behind a lexan window. What happened to the keyboard? It has been
replaced by custom logic that passes converted handlebar keycodes or
software-generated commands. This system is intended for on- the-road text
capture (not final editing), and thus connects with the HP via a front-panel
RS-232 connector.
The third system is the "bicycle control processor" (BCP), based on a 32K
Motorola 68HC11 board. This low-power machine embodies all of the bike's
real-time control and monitoring functions, including handlebar keyboard code
conversion, local network control (linking the other systems with each other),
electronic compass processing, control of solar battery charging, security
system supervision, diagnostics, status display, and so on. Assisted by about
50 IC's, this processor essentially runs the bicycle.
Computer number 4 is a speech synthesizer that speaks any text file transferred
to it. The value of this on the bike is threefold: I can have the system read
back my own text or incoming messages, and it is a handy way to reduce the
volume of identical questions from curious bystanders. ("I am the Winnebiko,"
it says, either at predefined intervals or under radio control, going on to
explain the basics of this strange contraption). The speech board can also
respond to a security alert by saying "Please do not touch me!" in a
robotically threatening voice.
The fifth system is known as a "terminal node controller" -- a PacComm
product that handles packet data communication via radio. An unusual breed of
computer network has quietly appeared in the last 2-3 years, a sort of digital
anarchy of the airwaves, a computer network without corporate substrate.
Anybody with a ham radio license and a bit of equipment can participate --
sending mail cross-country, transferring files, conferencing, and so on. The
network is young, but already offers coast-to-coast trunk connections,
automatic message forwarding, dozens of linked bulletin board systems, and its
own orbiting satellite mailbox. With packet operation possible from the
bicycle via the handlebar keyboard and LCD display, I can communicate data from
a campground or while pedaling. Ain't technology wonderful?
The handlebar keyboard itself is simple: four pushbutton switches are buried
in each foam grip, spaced about .75" apart. I type in a binary code, sort of
an ASCII with decoded zone bits: my five strongest fingers, three on the right
and two on the left, produce the lower-case alphabet; the right little finger
capitalizes. The left little finger is the control key, its neighbor selects
numeric and special keys, and those two together cause the others to take on
system level meanings such as file operations and major edit functions. In
practice, it's easy -- a lot like playing the flute -- with each combination
accepted by the system when all buttons are released.
So much for bicycle data processing. Now let's look at the other facilities...
The mobile ham radio station (KA8OVA here) is a multimode 2-meter rig from
Yaesu. In addition to handling data communication, it allows me to stay in
regular voice contact with Maggie (my recumbent-borne traveling companion).
Bicycle touring without some form of communication is frustrating, as anyone
who as ever squinted into the mirror for minutes at a time well knows. "What
happened to him? Is he OK back there?" With a boom microphone built into my
helmet and a push-to-talk switch on the handlebars, Maggie is never far away
(effective bike-to-bike simplex SSB radio range is over 2 miles). Of course,
having 2-meter FM capability on the bike also connects me to a huge network of
ham radio operators: I store the local repeater frequencies into the radio's
memory as I approach an area, and periodically identify myself as an incoming
bicycle mobile. This has led to a number of interesting encounters and places
to stay. And -- through the repeaters -- I can make telephone calls directly
from the bike.
A CB radio is also on board, culturally useless by comparison, but still handy
enough to justify its weight. I can talk to truckers, hail a passing motorhome
for water (this saved my life in Utah), and chuckle at the residual good buddy
subculture that still hangs on long after the death of the great CB boom.
System security is an issue when living on a machine that looks like something
from NASA. It's not that people try to steal it -- most are intimidated by the
technology -- it's just that some let their curiosity extend to flipping
switches and tinkering. To alert me to such behavior, I built in a security
system (based on the UNGO box) with vibration and motion sensors; when armed by
a front-panel keyswitch, any disturbance causes transmission of a tone-encoded
signal that sets off my pocket beeper up to 2-3 miles away. Maggie's bike has
a motion sensor also, and plugs into a front-panel jack when the two machines
are parked side-by- side.
Other radio-related devices include a digital shortwave receiver, a Sony
Watchman micro-TV, a VHF weather radio, and an FM stereo. Naturally, there is
also an audio cassette deck, for sometimes it takes more than a granny gear to
climb a mountain...
Speaking of gearing, the bike is equipped with some unusual mechanical
hardware. A custom 36-speed crossover system of 3 derailleurs provides a
16.9-inch granny gear, a 23-inch "high granny," and half-step from 33 to 144.
With the Zzipper fairing and the recumbent's aerodynamic advantage, I can
cruise comfortably at 15-17 mph (assuming a good breakfast and no unfriendly
winds). Peak speed so far, flying down a mountain, was 50.1.
Stopping power is critical with my 400-pound gross weight, of course. Moving
that much stuff downhill at 50 miles an hour is profoundly exhilirating... but
stopping is another matter. The Winnebiko II has three brakes: a Phil Wood
disc actuated by my left hand and a pair of Mathauser hydraulics controlled by
the right. The disc is nice for speed regulation without rim heating effects;
the hydraulics will stop anything, dramatically outperforming the various
mechanical models I have tried and discarded over the years. To control them
with a single lever, I machined a header for the master cylinders, with a
sliding cable stop and proportional transfer bar to permit a variable
front-back braking force ratio.
The frame itself was custom made by Franklin Frames of Columbus, Ohio -- after
I did enough brazing in my basement to convince myself that framebuilding is an
art form. The geometry is entirely custom, suited to my giraffe body and the
special requirements of all this on-board hardware.
Power for the electronic systems is derived from a pair of Solarex photovoltaic
panels, producing 20 watts in full sun (roughly 1.3 amps total into the pair of
4 amp-hour batteries). These new SX-LITE units lack the traditional glass and
aluminum frame, and are each 12.5 X 17 inches. Since they can pump enough
current into the Ni-Cads to overcharge them, I have built in extensive power
monitoring and control circuitry: A digital panel meter with a thumbwheel
switch can show instantaneous current into or out of each battery (as well as
any system voltage), and the BCP can throttle back the charging process if its
calculations indicate that the batteries are full (% charge values are
displayed on the console).
Other voltages besides the two 12-volt battery buses are needed throughout the
system, and this is one of those areas that can cause significant overhead if
attention isn't paid to losses. There is a small aluminum box containing
LT1070-based switching supplies that coolly provide 3, 5, 6, 9, and -12 volts
(all available on the front panel for external accessories). Considering the
special requirements of a bicycle system, the extra design effort here has paid
off well: when the two processors required for bike monitoring and text
editing are active, total system current drain is only 130 milliamps. A sixth
power supply, unrelated to the others, is mounted up front with a coiled cord
to allow battery charging if I have gone too long without sunshine.
Instrumentation on the front panel is largely geared to the major electronic
systems already described, but there is also the obligatory Cat-Eye Solar to
display speed, distance, cadence, and so on. This elicits interesting comments
from fellow bikies, who stare at the machine in awe then suddenly recognize
something familiar. In addition, there is an altimeter (useful on mountains,
and also helpful in predicting weather conditions), an Etak electronic compass,
time/temperature display, and assorted system status indicators.
Mechanically, the electronics package is designed to separate from the bike
with a minimum of effort. I open 3 toggle clamps, unplug 6 waterproof
connectors, and take it into the tent at night, yielding a "tent control
system" just as useful as the mobile variety. The 40-pound unit handles heavy
downpours with no problem -- with the fairing and velcro-on waterproof covers,
it has withstood all-day rides that quite saturated my Gore-tex. So far, the
system has suffered shock and vibration without incident, unfolding easily for
service but surviving heavy abuse on the road.
Safety factors are always a major concern when you habitually press your luck
by living fulltime alongside logging trucks, drunks, motorhomes, and the
routine madness of the highway. I have become a firm believer in helmets,
reflectors, orange flags, and GOOD lights. Bicycle Lighting Systems offers a
line of industrial-grade products that quite outshine the typical bike lights;
I went with a 7-inch yellow barricade flasher that makes me look like a roving
hole in the road, a 2-inch red taillight, and a 4-inch sealed-beam headlight.
In addition, I have recently added a Cycle-Ops halogen helmet light, which has
the delightful characteristic of putting light where I'm LOOKING, not just
where the bike happens to be pointing. (Admit it. You too have zigzagged
drunkenly through neighborhoods at night, trying to highlight street and house
number signs...)
Finally, the machine is equipped with all the usual bicycle touring gear:
stove, food, clothing, tools, candles, medical supplies, microfiche
documentation library, flute, binoculars, camera, maps, digital test equipment,
spare inner tubes, frisbee, coffeemaker, office supplies, butane soldering
iron, and so on. My tent is a vast "Peak Pod 4" from Peak 1, very much in the
porta-condo class at 108 square feet under cover. Other outdoor gear -- North
Face down bags, Gore-tex rainsuit, Patagonia bunting, polypro underwear, and so
on -- is undergoing constant revision as fabric technologies continue to
improve. There... a marathon overview of the Winnebiko. If any of this seems
insane, think about gravity and how long I would continue to drag around
something that isn't practical (and, preferably, multifunctional). This whole
adventure is a wild blend of serious business and fun -- a case of personal
computers and technology carried to an exquisitely mad extreme.
Thanks to all who helped make it possible!
-- Steve
