by 50% last year, the prize purse for
the Materials Challenge this year was
also worth $500,000.
LIGHT RACERS
CHALLENGE
Unlike the first two challenges,
Spaceward’s Light Racers Challenge
isn’t part of their NASA Centennial
Challenge contract. Instead, non-NASA donors sponsored this fun
challenge. To win, Light Racers had to
drive down a 60 foot long track
solely under beamed energy. Their
energy source was the light of a high
intensity spotlight. The prize purse for
this year’s Light Racers competition
was worth $10,000.
THE 2007 CLIMBERS
I didn’t realize how serious these
climber teams were until I learned their
registration fee was $5,000 — which
increased to $7,500 or even $10,000
as competition day approached. A total
of 22 teams applied for the 2007 challenge. Of them, eight completed their
climbers in time for the two qualifying
rounds held before we arrived. The first
qualifying round took place indoors on
a short ribbon suspended from the
ceiling. The second qualifying round
took place outdoors on a 100 foot tall
ribbon suspended from a crane.
Of the eight climbers at the
qualification rounds, all qualified
indoors but only four qualified
outdoors. We were able to visit the
eight climber teams and two climber
displays during our Saturday and
Sunday visit. Here’s what we learned
from these enthusiastic teams.
SIDE NOTE
Since it’s important that climbers
carry a large payload at high speed, the
Spaceward Foundation developed the
following scoring equation.
Score = (payload weight x speed) /
(climber weight + payload weight)
So for example, a 10 kg climber
carrying a five kg payload at an
average speed of 2.5 meters per
second (m/s) would earn a score of
( 5 x 2.5)/( 5 + 10), or 0.83.
space. Their 10 kg ( 22 pound) climber
is square in shape and nearly 12 feet
across. This was the Kansas City Space
Pirate’s second year at the Spaceward
Games. They built their climber last year
for $50,000 and spent an additional
$35,000 upgrading it for the 2007
games. The Space Pirate’s climber
contains a mix of 800 dual and triple
junction solar cells. To protect their
fragile solar cells, the cells are mounted
within balsa wood frames and suspended within the climber’s airframe.
The climber travels the ribbon via
two drums clamped to the ribbon and
driven by an electric motor. The
drums pinch the ribbon hard enough
that the climber cannot slip down the
ribbon. Commands to climb or
descend are sent to the climber
through a standard hobby remote
control (R/C). To even out power
fluctuations, the Space Pirates
incorporated several 2.7 volt super
capacitors into the climber’s avionics.
Sunlight is beamed to the climber
through an array of 19 mirrors. Each
mirror array consists of nine closet
mirrors mounted into a frame that
allows team members to tip and swiv-
■ FIGURE 2. The Technology Tycoons
climber, ready to strut its stuff.
el them. Each mirror array incorporates a targeting system built from
reflective tape and two pieces of glass.
Because of the spacing between
the tape and glass, mirror operators
see a projected red dot at their array’s
target. Each operator only has to keep
his or her dot fixed on the climber.
The combined light from the mirror
array creates a beam of light at the
climber 15 times more intense than
natural sunlight.
TECHNOLOGY TYCOONS
Our next visit was to the
Technology Tycoons of Westmont
■ FIGURE 4. Notice that the arrays of
solar cells are mounted within balsa
wood frames in this upside down view
of this climber. Each frame is free to
jostle to a small extent within the
climber’s airframe.
KANSAS CITY
SPACE PIRATES
The Kansas City Space
Pirates consist of several
families with the goal of
lowering the cost of access to
■ FIGURE 3. Checking voltages
is one step in prepping the
Kansas City Space Pirates
climber for its ribbon ascent.
March 2008 85