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EEs take EV for a ride

Brian Fuller

1/4/1999 1:54 PM EST

EEs take EV for a ride
Greg Hanssen bounces around with youthful energy showing a visitor the sleek, Buck Rogers lines of his electric car at, of all places, a gas station in the smoggy heart of Southern California.

"Let's go for a ride," he said.

Buckled in, Hanssen steps on the accelerator, and the General Motors EV-1 whooshes offwith the g-force of a jet, speeding onto the 405 freeway in the commuter lane, past backed-up motorists, their eyes widening as we whip by.

Save for the soft whine of the electric motor and the whir of the special, narrow 50-psi tires, Hanssen's two-seater is quiet and smooth. A display tells him how much juice remains in the lead-acid batteries and how much range he has left before the car needs a charge.

It's simple — too simple, in fact, for Hanssen and several other engineers who have taken to the EV-1s like ducks to water. In the two years since General Motors introduced the cars, engineers have not only leased them, they've hacked into the on-board computers, deciphered data streams and designed special cockpit displays to know more about their vehicles. GM had to "dumb down all the instruments, which is frustrating because in engineering, we want to know everything that's going on," said Phil Karn, an EE at Qualcomm Inc. (San Diego) who is writing a book on Internet encryption, due out next summer.

Hanssen, Karn, Dave and Jean Kodama, Peter Ohler and others make up a small but dedicated group of EEs involved in electric cars, car clubs and car Web sites. Clustered in California, where GM leases a majority of its EV-1s, they fill those sites with all manner of information — from GM spec updates to trip plans, topographic maps and GPS coordinates of charging stations.

To a person, the engineers use their EVs to the virtual exclusion of all else, although some hang on to an ICE — that is, internal-combustion engine — car for the few trips that EVs can't handle. Dave Kodama, a consultant engineer, photographs stars and has to use a conventional car to drive deep into the desert. "You have to have the right tool for the right job," he said.

GM doesn't sell the EV-1 but has been leasing them since Dec. 5, 1996. Some 500 are now out on the road, with the first-generation vehicles leasing for about $400 a month, when tax incentives are factored in. In some areas, utilities give drivers a rate break to encourage the technology.

No other subset of EV enthusiasts — buffs include the likes of actors Ed Begley Jr., Ted Danson and Danny DeVito and Star Trek cinematographer Marvin Rush — can do to their cars what the engineers do. While applauding GM for having the courage to build the line, they were frustrated by the lack of data coming off the on-board computers and by the tight-lipped engineering community at the big automaker.

"Is it a car or is it a laptop on wheels?" said Karn. "We want to know what GM is thinking."

They didn't wait long to find out.

Hanssen stood over the technician's shoulder at the 5,000-mile checkup on his EV, watched him rotate the tires and, more importantly, download data from the car's seven computers.

"I thought: this would be cool if I could access this," Hanssen said. Inveterate tinkerers, the EEs are just plain curious about how it works. "We want to know how much power it takes to go uphill with a 200-pound passenger and I'm running the air conditioner, for example."

Pooling information, Hanssen, Ohler, Dave Kodama and others soon figured out how to hook up a serial cable to a 16-pin connector that sits on the floorboards near the driver's left foot. Hanssen attached an oscilloscope and set about recording the data stream as audio to a digital audio tape recorder. Using a digital sound card that his company, Zefiro Acoustics, makes, he was able to transfer the data to a PC.

With .WAV files now in his computer, Hanssen wrote a Turbo C program to parse the ones and zeroes. He adapted an old TRS-80 model 100 laptop to read the data in real-time, decipher it and display it.

Heading out to the desert, he hooked up with legendary experimental-plane pilot and designer Burt Rutan, and the two took turns driving their EV-1s over a dry lakebed to collect more data.

Rutan wasn't Hanssen's only ally in his quest to understand the inner workings of the EV-1. Ohler, a software engineer for middleware vendor Tibco (Palo Alto, Calif.), had written a simple-data-analysis program on his PC, but it wasn't capturing the data well enough. He hit upon the idea of using his Palm Pilot, which buffered the serial port faster. (Ohler's Palm Pilot code is free to download online.

"I recognized the basic block pattern and just starting pushing buttons," Ohler said. "You figure what buttons work where."

For Ohler, tweaking electric vehicles is nothing new — he's on his third. The first was a retrofitted pickup truck with wet-cell batteries. Next came a Toyota Paseo, which had a range of 34 to 40 miles in the summer, "but you could squeal the tires and burn rubber." The EV-1 has greater range, more amenities.

Another tinkerer is Michael Schwabe, a 25-year test-engineering veteran, who has designed a wireless interface to let EV owners monitor the battery-charging process remotely. Using a set of the RF modules made by Linx, Schwabe built a transmitter and a receiver running in the unlicensed 900-MHz band. The transmitter sits in the car, connected to the diagnostic port, which outputs a stream of data. The receiver, linked to a laptop, receives the data and decodes it. Coupling this scheme with Ohler's program, a user can tell exactly the state of charge and the amount of charge current going into the battery.

Getting the battery charged is a constant preoccupation for drivers. When the EV-1 was first introduced, the infrastructure in California was sparse — no equivalent to a gas station every few blocks. But that didn't trouble Jean and Dave Kodama, who commute to work, run errands and turn heads in his-and-hers EV-1s.

"I don't feel comfortable relying on the infrastructure," said Jean, an ASIC designer with Vixel Corp. (Irvine, Calif.). "I prefer to be self-contained. I don't like to go out and have to have a charge to get back."

The last two years have seen phenomenal growth in electric-charger infrastructure. The discount chain Costco is installing chargers as a matter of corporate policy, many malls are putting them in and even some gas stations have them. The Fry's Electronics chain, popular with the techno-crowd, has chargers at some locations, too.

It takes up to three hours for a full charge. A second generation of chargers with 50-kW capability would cut that to 12 to 15 minutes.

The charging dilemma is offputting to some. A sign hangs outside Jean's office at Vixel offering free test drives of her car, which is usually hooked up to a company-installed charger in the parking lot. Not many people have signed up so far. "People complain about the range, but they live three times closer to work than I do," said Jean.

And if you do get into a pickle — well, you're an engineer, you'll figure it out. On a trip to Yosemite, for example, Hanssen used 10-gauge wires and alligator clips to hook into a house circuit breaker for a charge. Kids, don't try this at home.

Ever since GM unveiled its 1999 model in Los Angeles on Dec. 5, Dave, Jean and Greg have been counting the days till they can get their hands on one. For the Kodamas, that could happen later this month. The car doubles the EV-1's 50-to-75-mile range with its NiMH batteries, has more integrated electronics and is 30 pounds lighter.

GM has indicated that its third generation, expected after the turn of the century, will be cost-competitive with gas cars, but Dave Kodama believes he's there now. "We drive this car for a penny a mile" in fuel costs, he said, "a sixth the cost of a gas car."





dblaza1

5/23/2011 12:33 AM EDT

Its been a long strange trip but the Chevy Volt is here and EETimes has our hands on it. We will start the "Drive for Innovation" in June 2011 so watch for more details and the great irony here is that Brian Fuller gets to drive it around the US more than 10 years after he wrote this story!

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