How I Fell in Love with the Tesla Roadster

Don Cox is a Professor of Electrical Engineering and the Harald Trap Friis distinguished chair at Stanford University. He spent 25 years at Bell Laboratories and Bellcore developing revolutionary technology for what is now referred to as "cellular phones." He has served on the board or as an officer of several Silicon Valley public companies and sits on technical advisory boards of many others. In this week’s blog entry, Don explains why he wanted to be among the first customers to receive a Tesla Roadster. (Don, pictured above with his wife, Mary, checks out the Tesla Roadster.)

My wife, Mary, and I were invited to be a “guest blogger” on the Tesla Motors website. This is a big honor for us. It is an easy task because of our high regard for the Tesla Roadster and the people at Tesla Motors.

We have had a long-standing interest in electric cars because of their potential both to help reduce our country’s dependence on foreign oil and to save our environment from pollution emitted by cars that use internal combustion engines. We thought you might be interested in our experiences and investigations in becoming Signature One Hundred members, the group that has reserved the first Tesla Roadsters to come off the production line. Our story might be called, “How we fell in love with the Tesla Roadster and Tesla Motors.”

The first time that our son Earl, his wife, Nagin, and I saw and rode in a spectacular, beautiful Tesla Roadster was at the Big Event in Santa Monica, Calif., on July 19. What an exciting experience for us!

There were several issues that we needed to resolve before “signing up” as a Signature One Hundred member. The first issue was whether Earl and I could get into and sit in the small Roadster – we are both 6’4” tall. My attempt was first, and it was surprisingly easy. Sitting in the driver’s seat was snug but comfortable. The task was even easier for Earl, who is many years younger.

The question of whether Tesla Motors could build a working car was resolved by watching the cars circle around the big launch party all night, and by riding in a car as it left the hanger and catapulted its occupants to high speed on the tarmac outside. The ride was too short and too exciting to note how fast we actually went on the speedometer!

We questioned many Tesla Motors engineers about the design details of the car. All the engineers displayed high competence and willingness to discuss the car and design choices made. Of course, we scrutinized the all-important battery pack in detail. Packaging more than 6,000 laptop cells is an economical and reliable approach to this key electric car component. Tesla Motors has taken a careful approach to temperature management by circulating temperature-controlled liquid through the battery package and by continuously monitoring temperature, cell voltage, and currents with a microcomputer. The Li-ion cells provide the most energy- and power-efficient battery available at this time.

The 3-phase, 4-pole induction motor is the simplest and most robust motor that can be made. It has only one moving part and no brushes. The Tesla Roadster has a highly efficient and rugged design, which should be very reliable as well as provide exceptional torque over the entire speed range. The high-efficiency motor controller is conservatively designed too. The aluminum chassis and carbon fiber body also appear to be well designed. The mechanical integration of the electrical components with the body, suspension and wheels has been done effectively.

Remaining questions were: Do they understand the need for extensive testing of the prototypes and can they manufacture the cars in quantity? There are several electric car designs floating around with minimal testing plans and no clear path to production. The Tesla Motors engineering staff outlined ongoing testing and plans for a comprehensive overall test program to ferret out needed design improvements. Talking to Tesla Motors manufacturing managers and engineers yielded the outline of a well-thought-out plan to produce the first 100 cars and also a plan for continuing production beyond the first 100.

Another question we looked into was the economic viability of Tesla Motors, the company. We convinced ourselves that Tesla Motors has significant funding that should support continuing design, testing, and production activities. The clear popularity since we signed on leads one to believe that others see the value in the Tesla Roadster too, so there appears to be a market for the car.

At the end of the Santa Monica event, we were very impressed with the prototype cars, with the Tesla Motors engineers, and with the company overall. But we were still “on the fence” about “taking the plunge” into Signature One Hundred membership.

The deciding input was provided at a presentation at an Electric Auto Association (EAA) meeting in Palo Alto, Calif., on August 5. J.B. Straubel, Chief Technical Officer at Tesla Motors, gave an interesting and comprehensive description of the Tesla Roadster design, the design tradeoffs, some progress of testing, and many issues for electric cars. He skillfully fielded a myriad of questions from the large EV crowd. His knowledge of EV issues, design tradeoffs, and alternatives was impressive.

A Roadster prototype was demonstrated in the parking lot after the talk. It was another very positive Tesla Motors event. On our way home, Mary stated that this was the first such technical presentation she had heard in a long time in which the speaker sounded like he knew what he was talking about! She thought we should join the Signature One Hundred group at once. We did the following week.

How did we become interested enough to attend the Tesla launch event in Santa Monica? Earl and Nagin leased a General Motors EV-1 for several years until GM “pried it away from them.” During that time they let us use it several weeks. (Yes, it was driven from Los Angeles to Stanford and back!) They became very attached to that car and Mary and I did too.

We took many students and others for rides and let quite a few of them drive it. Everyone loved the EV-1 and many asked how they could get one – too bad none was available by then. It was a great joy for us to drive the EV-1 whenever we could. It was not just a toy; it was a useful car. Earl commuted with it for several years up to 30 miles each way on freeways, and Mary drove it to work 10 miles each way when it was “her turn” with the car. Plugging it in at night and unplugging it in the morning was much easier than trips to gas stations.

Of course, a major limitation in the EV-1 was the batteries available at that time, first lead acid and later nickel-metal hydride. It was a sad day when GM took the car back and crushed it in the desert along with all the others. Earl then followed closely the several electric car projects, and I looked at some of them too. None passed our careful scrutiny and none appeared to have a path forward to produce a significant number of cars. We did not want to have an “orphan” car. Then along came the announcement of the Tesla Motors event and we were lucky to secure invitations to it. As they say, “the rest is history.”

We have visited the Tesla Motors San Carlos, Calif., headquarters since joining the Signature 100 and toured the engineering and component testing areas. One tour by Gretchen Joyce, vice president of sales at Tesla Motors, and J.B. provided additional comprehensive information on designing, testing, and manufacturing the Tesla Roadsters. Their testing at all levels, from components to subassemblies to complete cars, is very thorough. The computer-controlled dynamometer they built themselves for testing the motor and electronics shows a high degree of ingenuity and resourcefulness.

A second tour included another ride in a Roadster prototype and discussions with several Tesla Motors people. They are testing and improving designs where needed, like any highly competent company does when developing a completely new product. In each interaction, we become more positively impressed with the design and manufacturing team and the quality of the company in general. Our discussions of design choices have always shown excellent knowledge of the alternatives and careful exercise of good engineering judgment in making design decisions. In some cases we might have chosen different design alternatives, but the Tesla Motors choices appear to be the right ones for the company’s goals.

Will the Tesla Roadster be a perfect car? No complex machine is ever perfect, but it appears to us that the Tesla Roadster will be a truly great machine without any serious flaws.

It was a lot of money for us – we are not among the super rich. However, we did not feel that we could afford to pass up the opportunity to own such a splendid and unique car.

It may sound like we have been “brain washed” by Tesla Motors, but I am certain that is not the case. Mary and I are conservative, cautious, technical people who have spent many years assessing technical promises and hype. I spent 25 years in industry, working at Bell Laboratories and Bellcore and involved in developing revolutionary technology for what is now referred to as “cellular phones”. I am now a Professor of Electrical Engineering at Stanford. I have been on the board or served as an officer of several Silicon Valley public companies and startups, and I am or have been on technical advisory boards of several others. Mary has been a chemistry professor for more than 30 years in New Jersey and California. Between the two of us, we have a lot of background in the basic technologies in electric cars, in launching new technologies, and in starting and running companies.

We have done considerable, diligent investigation of Tesla Motors, the car, the people, and the company. We are convinced that they have an exceptional collection of engineers and other professionals who have designed an outstanding car and will produce many of them next year. We are waiting enthusiastically to receive ours and are looking forward to Tesla Motors providing other exciting sports cars, practical luxury sedans, economy cars, and all types of electric vehicles that people need.