Hacking the wind
Silicon Valley's geek ethos pushed Rick Cavallaro to do the 'impossible'
Mountain View, along with its neighbors to the north and south, form one of the world's most industrious pockets of human civilization — Silicon Valley.
According to Mountain View resident and wind-sports enthusiast Rick Cavallaro, the real secret behind the success of Silicon Valley lies not in the companies headquartered here. Rather, he says, it is the inquisitive and fun-loving spirit of the region that makes it a powerhouse of innovation.
It was this geek ethos, which views problem-solving more as recreation than responsibility, that propelled Cavallaro to build a machine capable of doing something scientists said was impossible.
Last March, in a dry lakebed in the Mojave Desert, that machine — a wind-powered vehicle dubbed Blackbird — defied a principle long held to be true by sailors and those who understand the physics of sailing.
Cavallaro's cart "sailed" directly downwind faster than the breeze propelling it. In an unofficial run, he says, he actually quadrupled the speed of the wind, although official record-keepers only have Blackbird down for three times wind speed.
Because of a principle known as "lift" — the same principle that allows airplanes to fly — it is possible to sail diagonally downwind faster than the speed of the wind itself.
However, it had always been thought that a sailing vessel could only move directly downwind as fast as the air that pushes it. Cavallaro figured out a clever workaround to this problem.
As he tells it, Blackbird, which is equipped with a giant propeller that is connected via a driveshaft to the wheels, first gets pushed — propeller and all — by the wind; the forward motion of the car then turns the propeller, creating thrust.
Though it takes Blackbird quite a bit of time to get up to speed, once it does, a feedback loop of sorts begins and the car ends up traveling faster than the wind that initially got it rolling.
This may sound to some like the fabled "perpetual motion machine." But it's not, Cavallaro explains. "Once the wind stops blowing, the cart will eventually stop."
For those interested in delving deeper into the science behind Blackbird, there is a lengthy feature story in this month's Wired Magazine about Cavallaro and his cart.
In a way, Blackbird was propelled by two kinds of wind. Obviously, there were the air currents swirling around atop the dry desert lakebed. But that was only part of the equation.
The other was the air coming out of the mouths of friends, colleagues and other Silicon Valley personalities that encouraged, and in some cases, facilitated and helped finance Cavallaro's project. These are people who love equations, never shy away from challenges and use the word "hack" to describe the way in which they have arrived at an inventive, do-it-yourself solution to a complex problem.
Cavallaro might have never even thought about building Blackbird if it weren't for a friend and fellow nerd named Al Alcorn, an Atari engineer and the creator of the game Pong. It was Alcorn, after all, who first posed the question to Cavallaro: Could a ship outpace a balloon being carried downwind?
John Borton, Cavallaro's friend and colleague at Sportvision — the Mountain View sports technology company, responsible for the virtual yellow, red and blue lines used to mark the downs and line of scrimmage in televised football games — helped him build the vehicle after first egging him on.
After Cavallaro figured out how he could hack the wind, he began engaging with both supporters and detractors through online forums — another outgrowth of Silicon Valley geek culture.
"People said I was stupid," Cavallaro said — that it couldn't be done. But Borton had a different reaction.
"I told him he would be stupid not to build this thing," Borton says.
Cavallaro then secured funding from Google and a Santa Cruz wind power company called Joby Energy — connections he had made over his more than two decades in Silicon Valley.
"There is a company culture out here that if you are doing something cool, you will get backing," he explains.
That culture worked to Cavallaro and Borton's advantage again when Sportvision — where they serve as chief scientist and director of manufacturing, respectively — allowed them to use company tools and workshop space to build the cart. With its 14-foot-high tower that supports a propeller of two, 8-foot-long blades, it "definitely couldn't fit in my garage."
"Your employer wouldn't let you do that kind of project in their shop in most places," adds Borton — even if they were doing all their work after hours, as the two did.
Cavallaro says he has often wondered why this region has become the technological mecca it clearly is. He speculates that it could be some vestige of the old west — California, being one of the last frontier states in this country, may continue to draw people with a strong pioneering spirit.
The weather doesn't hurt either, he notes. "I don't want to name names," Cavallaro says, "but I couldn't see a project like this being done in a state where it is cold in the winter and people stay inside watching TV."
Whatever the case, Borton agrees with Cavallaro when he says that tech-oriented individuals are "the kind of people that we involve ourselves with, and there is no question that Silicon Valley is the place where those people want to be."
Next up: upwind!
In the months to come, Cavallaro and Borton plan to make a few tweaks to their design and create a cart that can travel upwind faster than the speed of the breeze bearing down upon the front of their cart.
They will do this by switching out their propeller with a turbine. Instead of the wheels turning the vehicle's giant blades, the blades will now turn the wheels.
Cavallaro believes the new vehicle will travel 1-1/2 times the speed of the wind. He and Borton have crunched the numbers, and both of the men express the utmost confidence in their new endeavor. It is an attitude that not only speaks to the trust they have in their own ingenuity, but also stands as a testament to the boost they have been given by a supportive community.
"It is possible," Cavallaro says. "I guarantee we will do it."