by Jean
Thilmany,
Associate Editor |
When Bob Montgomery
brought his motorized surfboard to market, he expected engineering challengesbut
maybe not as many as he eventually met. He didn't think, for example,
that he'd have to become an expert in choosing and integrating
engineering technologies or in engine design.
A look at the process he went through as he started a company from the
ground up provides a glimpse of how engineering technologies can be the
hidden driver in bringing a new product to market. Montgomery hired engineers,
made decisions about purchasing engineering technologies, and implemented
a just-in-time manufacturing systemnot to mention the marketing
of an entirely new product successfully feeling his way through
each step of the process.
Sixteen years ago, Montgomery, a former professional surfer and construction
foreman, turned on his garage light in Capistrano Beach, Calif., and sat
down to sketch the first rough design for an idea he'd been playing
around with a while: a motorized surfboard he calls a jet board. He said
his concept would bring surfing to the masses, no matter where they live,
as long as it's near a body of water, whether that body is ocean,
lake, or river. The Powerski Igniter 330 is newly available in the United
States. Riders stand on it like a surfboard, and although it includes
a mechanism for maneuvering, riders also steer it like a surfboard, by
shifting their body weight. The Igniter 330 is now distributed in 35 countries.
In August, it earned Coast Guard approval for U.S. distribution, Montgomery
said.
Montgomery's 16-year journey from that initial rough draft to jet
board production was by no means easy. Along the way he founded a company,
Powerski International, in San Clemente, Calif., and hired an engineering
team, led by Bjorn Levine, to design and patent a two-stroke, water-cooled,
45-horsepower engine that weighs about 40 pounds. The engine was specially
designed to be light but powerful, to be compact with a sleek, side profile,
and to perform well as it moves through water. Montgomery himself designed
the jet-board hull, hollowing out the space beneath the rider's
feet to house the engine. He hand-made a number of prototype hulls from
composite materials.
CAN'T DO IT BY HAND
Between the first design on paper and actual production, Powerski engineers
made thousands of changes to the hull, engine, and other components. After
he built an initial model of the hull in his garage, Montgomery needed
an engine to motorize the surfboard.
"I wanted the engine to be low-profile," he said. "Surfboards
are flat. They don't have big humps on them. There was no engine
out there to fit that profile. I had to pull an engine off the shelf,
an outboard engine, which I placed in the hole in the hull horizontally.
It was ineffective. It wasn't the correct design."
He would have to do it himself. Montgomery hired Levine, who had designed
motorcycle engines successfully in the past. He created a 330-cubic-centimeter
engine, known as the SuperTorque XT, that fits nicely within the hull's
profile.
"I'd designed the hull and originally it had a sort of bowl
in it," Montgomery said. "I said to Bjorn, 'I need
you to make an engine to fit this bowl.' And he did it.
"It had to be long, like a little torpedo engine, and narrow, because
the board had to be narrow," Montgomery said. "And it couldn't
be very high.
"There's a host of design and engineering challenges when
you design a surfboard and add an engine," he said. "Water
intrusion was one of them. When you sit on the board, it sinks. We had
to make it not sink. We've come up with inflatable seals to equalize
the pressure around the hatches. Then, the exhaust on the engine had to
have one-way valves so water couldn't get into the engine."
 |
| The motorized surfboard invented
by Bob Montgomery includes a 330-cubic-centimeter engine, known as
the SuperTorque XT, specially designed to fit within the hull's profile.
|
Montgomery found that designing a new engine had to be done within a
computer-aided design package to allow for the complexity of the parts.
"At first, I thought I could do without a computer during the initial
design phase and keep track of changes, but I couldn't,"
Montgomery said. To help in the design, he chose Pro/Engineer from PTC
of Needham, Mass.
Powerski engineers now use the CAD package to design the engine, the hull,
and everything associated with the jet board, including the steering handle.
While his business was in the start-up stage, Montgomery built about 30
different prototypes of the board by hand, shaping the molds himself.
"But as I sit here today, I don't have a single blister
on my hands," he said. "Because now we're designing
the whole board in CAD."
Powerski also uses a number of analysis modules, also from PTC, to test
the product digitally before building a prototype. This enables engineers
to work out the early kinks in their designs, said Steve Ryan, a production
engineer at Powerski.
"We have an area on top of the board that's for air intake,
to get air to the carburetor," Ryan said. "We made a design
change to this, and we wanted to find the volume of air that's
going through the area. We could analyze that, which is wonderful.
"We can do stuff like cabling and welding, and stress analysis
if we need to," he added.
The engineering team had to deal with five significant natural forcesweight,
buoyancy, hydrodynamic lift, drag, and thrustwhen designing the
Igniter 330. The jet board combines a high ratio of thrust to weight with
a hull design that stabilizes the craft at all speeds, Montgomery said.
The board was designed to place the center of gravity directly underneath
the rider, which also stabilizes the board. The design lets riders execute
high-thrust turns by shifting their weight, he added.
When the jet board prototype was ready for water trials, Montgomery and
his team placed sensors on the board and on the engine, to transmit data
about water flow, hydrodynamics, ignition, and fuel injection. They transmitted
the data to a Hewlett-Packard mobile workstation that they took with them
to the beach, not even bothering to protect it from ocean spray. The workstation
held up just fine.
SURFING INSIDE THE COMPUTER
Because Montgomery shaped the prototype boards by hand, the hull met his
design specifications, but it wasn't symmetrically perfect, which
it needed to be. It wasn't enough to simply measure the hull and
pass the coordinates on to manufacturers. The geometry and specifications
for the hull shape that Montgomery eventually approved had to be contained
within the company's CAD system, so engineers could tweak the part
until it was symmetrical. They also had to have digital tooling specifications
to pass on to parts suppliers, Ryan said.
Computer-aided manufacturing techniques need a coordinate measuring technique
to achieve exact correspondence between the numerical model and the real
component. Powerski engineers needed to produce a digital, numerical model
from the hand-built hull.
For the reverse engineering of the hull, the team used scanning technology
called Advanced Topometric Optical Sensor, from Capture 3D of Los Angeles.
The digitizing system was run over the hull to measure it in high local
resolution. Each single measurement generated up to 1.3 million data points,
which were merged into a digital file of the complete hull. Engineers
then shaped hull parts finely within the digital system.
Montgomery had taken his jet board concept beyond his garage in 1995,
when he founded Powerski International. He soon found the company growing
and the engineered parts morphing rapidly, as the design team tried to
come up with the perfect jet board concept. Now he needed a way to track
design changes and keep in touch with parts suppliers. In addition, his
company was becoming a far-flung operation because he hired engineers
located throughout the country. He figured, correctly, that they could
work together via technology.
 |
 |
| Although the hull of the Powerski
Igniter 330 was designed by hand, engineers imported the physical
prototype into the company's CAD system, which is from PTC. |
Shortly after implementing the CAD system, Montgomery and his team purchased
a product data management system called Windchill, also from PTC.
"If there's a change in our design here in the corporate
office, we can distribute that through the Windchill Web site, and everyone
gets updated immediately," Ryan said.
Jonathan Boyce, the director of automotive operations at PTC, said that
Windchill is intended to help track engineering change orders as well
as to track products and parts. That feature is particularly useful at
Powerski, which produces jet boards in more than one style.
"Powerski has a number of different configurations of its jet boards,"
Boyce said. "But even color configurations have to be managed effectively
in the data management system."
The application is also used to store data so that it resides in one central
location and engineers know how to get to it quickly.
Not only is the product data management system used to store information
and track change orders, it also doubles as the Powerski collaboration
system. Ryan said the system lets Powerski engineers around the company
meet on the Web to review files, mark them up, and hold conferences about
how the jet board is shaping up.
DELIVERING IN TIME
Powerski is using a just-in-time method of production. When a distributor
orders a certain number of jet boards, suppliers ship just enough parts
to company headquarters to assemble that many, which are then shipped
to the distributor. Jet boards won't be stockpiled in a warehouse,
tying up Powerski's dollars in real estate and inventory. Because
all manufacturing is outsourced, the collaboration software is used to
coordinate suppliers, shipping dates, and distributor orders, Ryan said.
"We're in production right now, and we're shipping
parts all over the world," he said. "We have about 340 parts
to coordinate with all the different vendors and with bidding and changes.
Without that technology it would be a mess."
The company also solicits proposals from suppliers via the Web site. "Instead
of having to distribute requests to every single manufacturer for a bidding
process, we've centralized it," Ryan said.
And when an engineer tweaks a part's geometry even as it is about
to be produced, the engineering team can speed the new dimensions to the
supplier via the Web site so the manufacturer can update tooling.
Montgomery's team made well over 400 machine-tool changes while
it worked on engine design. Before the company implemented the collaboration
technology, it sent all those changes to suppliers via fax, e-mail, phone,
or conventional mail.
"As we started up, we saw that this was the wrong way to do it,"
Montgomery said. "If there's a problem with our test units,
we want to make the updates as quickly as possible, otherwise it's
going to cost us money."
READY FOR A JET BOARD?
All systems are go for the eight-year-old company as it adds more distributors.
Montgomery expects jet boarding to become a popular water sport, akin
to surfing. The jet board design puts the center of gravity under the
rider's feet, rather than behind or in front of the rider. Controls
under the bottom of the hull also put the pivot point directly under the
rider's feet, for high-speed planing and turning, much like a surfboard.
Because the board is motorized, a rider can plane and turn on still water.
"Not everyone can be like the Beach Boys and have an ocean in their
backyard," Montgomery said.
And he's not shy about touting his product or boasting about the
amount of work that went into its design.
"This is a birth of a whole new water sport that will change the
direction of the watercraft industry the way the snowboard changed skiing,"
he said.
Whether that's true or not remains to be seen. But the amount of
work behind the engineered product certainly deserves recognition.
home |
features |
news update |
marketplace |
departments |
about ME |
back issues |
ASME |
site search
© 2003 by The American Society
of Mechanical Engineers
|