IEEE Spectrum November, 2016 - 52

COG CUT

14,115 FT

SUMMIT
OLYMPIC

13,380 FT

BOULDER PARK

13,060 FT

UPPER GRAVEL PIT

12,760 FT

BOTTOMLESS PIT

12,780 FT
DEVIL'S PLAYGROUND
START OF 4TH LEG
START OF 2ND LEG

RACE TO THE
CLOUDS: The course
has many treacherous
twists and hairpin
turns [in purple]
and had unpaved
sections until 2012.
Nevertheless, there
have been only five
fatalities since the
race began in 1916.
For the first time ever,
an electric car won
the race last year,
when another electric
vehicle took second
place as well.

16
START OF 3RD LEG
START OF 1ST LEG

15
DOUBLE CUT

GEORGE'S
CORNER

COVE CREEK
RAGGED EDGE

11,440 FT

11,900 FT

ELK PARK

GLEN COVE

SWITCHBACK
BELOW GLEN COVE
SUMP

10,900 FT

HEITMAN'S HILL

GROUSE HILL 11
11 MILE WATER STATION

BLUE SKY

GAYLER'S STRAITS

GILLY'S
CORNER

SKI AREA

BIG SPRING
BROWN BUSH CORNER

TIN BARN

10,560 FT

9,960 FT
HALFWAY PICNIC GROUNDS

9
9 MILE

ENGINEERS CORNER

HORSESHOE
HANSEN'S CORNER

8 MILE PIT ROAD

CRYSTAL WORK ROAD

START LINE 9,390 FEET

o w m u c h e f f o r t does this extracurricular activity consume? In some cases, more time than the coursework.
Aaronn Sergent, a mechanical engineering major, confesses to me that he puts in just 20 or 30 hours a week
on the bike project. He's almost apologetic as he tells me this
outside Uncle Sam's Pancake House, where the team has just
breakfasted on eggs and pancakes. It's 8:00 a.m, but the team

nov 2016

north AmericAn

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started this day at 3:00 in the morning, doing time
trials and tune-ups, well before the onslaught of
summer tourists. Now, bellies full, these kids are
about to go right into a second day of work back at
their rented house in Colorado Springs.
Or even a third day, maybe. Bonnell-Kangas gets
very little shut-eye: He texts me on the coming day's
plans well after I've fallen asleep, then does it again
at 2:00 a.m., well before I wake up the next morning. Many hours later, as I stagger off to catch a ride
to my hotel, I pass four of the students. It's early
afternoon, and they're blowing off steam shooting
hoops in the front yard.
Rest? Who needs rest?
The inverter problem defies an easy solution. The
Buckeyes can't buy an inverter locally, and they
haven't the time to airlift one in from the antipodes. So there the electrical subteam sits, hunched
around the dining-room table of their rental house,
tearing the broken inverter apart.
"The motor is synchronous, which means the
inverter has to keep up," Bonnell-Kangas tells me.
The rotor of a synchronous motor moves in lockstep with the rotating magnetic field. That field,
in turn, is generated by output from the inverter,
which varies in a repeating pattern, or cycle. The
faster the motor turns, the more cycles the inverter
must provide. But this inverter can crank out no
more than 500 cycles per second-enough to turn
the motor at 3,000 rpm. That's the redline.
"So we designed a control system to keep the motor
below that critical speed," Bonnell-Kangas says.
This is why the inverter's paralysis is such a big
deal. As things now stand, the students can't even
get the motor to turn at all. And if they can't fix
it, then it's good-bye to a year's worth of dreams.
Just as I begin to head back to my hotel, the problem is apparently found: two very well-fried fuses
in the power supply board. They got electrocuted
earlier during a tune-up.
"We reversed the polarity [the direction of current]," Bonnell-Kangas tells me. "That burned the
fuses, and that interrupted the power supply. We
can fix this." And they did.
It's things like these that make you appreciate
the sweat that goes into anything complicated: a
motorcycle, a car, a jetliner. Fix one thing and you
tee up another to fail.
Despite the frustrations, pressures, and compromises, they all can't imagine doing anything else with their
free time. When I ask Marc Ahlborg, an aerospace engineering major, why he chose this team rather than something
more aeronautical (surely there's a drone club?) he notes that
he rides a bike himself, as do most team members. Though
limited, the resources of this club are among the best at Ohio
State, he adds. Most come as in-kind gifts from sponsors.

PPihC

FINISH LINE

http://SPectrUm.ieee.orG

Table of Contents for the Digital Edition of IEEE Spectrum November, 2016