Nice article. Clearly they have done a tremendous amount of engineering work in a relatively short time.
I always like that "through the windshield, hands on the wheel" driver view photo angle...
OK, Martin is let go along with Wally Rippel (Aerovironment engineer for GM EV1, Caltech alumni). Thus, alienating any future Caltech or UIUC involvement. Believe me, words travels fast. I heard on a comment, something to the effect "..& his Stanford buddies", I assume this is JDS.
I will say, JDS background is impressive, his Stanford engineering background. The "engineering issue" (instantaneous torque curve of AC Induction motor, resulting in severe shockload to transmissions) had an incorrect response: a personnel issue, blaming Martin & his group (incl Wally Rippel). xxx made a mistake in engineering assessment..IT WILL LIKELY HAPPEN AGAIN. I heard about morale being at a low (earlier in the year).
Is this Drivetrain 1.5? (with the water cooling package for the motor, because the single speed would require higher rpm). What happened with the Death Valley testing? I can tell you, having been at CART (& Champcar) races & smelling burnt electronics (any EE major will tell you that sickly smell), that lack of heat dissipation will destroy electronics in no time. You often hear about Indycars doing ignition-box swaps mid-race, I believe this is heat-related problems. I remember one time where Sebastien Bourdais (Newman-Haas Racing) did such a swap, & they used WIRELESS to update the firmware in the pit-area! (pretty state-of-the-art).The Roadster's exceptional motor, too, is a tribute to Straubel's persistence. Tesla initially used a third-party transmission that included two gears--one to accelerate from a stop and the other to reach high speeds. The system gave the Roadster a top speed of more than 120 miles an hour. However, the shifting system routinely wore out after just a couple of thousand miles. So Straubel found a way to replace it with a single-speed gearbox. Early on, Straubel and his team had redesigned the patterned metal plates and wire coils at the heart of electric motors to improve both efficiency and torque. But the electronics feeding power from the battery to the motor still limited its output. To exploit the added torque, Straubel added higher-performance transistors and retooled the electrical connections between the motor and the gearbox. These changes increased the torque that the motor could deliver at low speeds and allowed the engineers to use a single-speed transmission without sacrificing either acceleration or maximum speed.
Xtrac recently solved the breakage problem in Offroad Racing: the severe shockload on trannies when a XXXX Class 1 buggy gets airborne & lands on the ground. The situation is not unlike the situation in a Tesla Roadster (2-speed tranny + AC Induction motor). I know this team XXXX (they are one of my best supporters, my Jumplive.com multimedia project), they are heavily sponsored by European-based sponsors: exhaust, torque-limiter, etc. They were using torque-limiters (similar to above for Tesla Roadster, see above) to de-tune the extreme response of the motors. There was a year of breakage for this XXXX team (2007), but finally this year Xtrac figured it out: XXXX got 1st place at the recent 08 San Felipe 250 (!). Their 1st win ever! They followed it up, with a 3rd place (podium finish) for the Baja 500. They just added another car: European driver, teamed with a young American hotshot driver. This team is on a roll.
Lesson learned:
It took TIME for Xtrac to do the empirical testing.
"In order to Push the Limits [ of Technology ], sometimes you have to EXCEED THE LIMITS"
-- Australian GP, Formula 1 race (2003?)
The tranny breakage issue is obviously 1 of the above problems, & this SH*T TAKES TIME TO FIGURE OUT!! xxxx has this "bizarre notion" that you can "throw money at the problem" & solves problems instatneously. Bzzzt..wrong! What "Reality Distortion Field" does this guy live in?? And, he is in charge of SpaceX?? ROTFL!! Wasn't there a recent failed attempt..again?
This is why xxx's impulsive response, by incorrectly blaming Martin & Wally Rippel, is such a black mark. Not only did it hurt current TM development, it probably jeopardized the entire company's future. You think any Caltech or UIUC alumni (or ANY engineering school alumni), will work for TM, knowing that the top management is engineering-foolish??
I've been repeatedly saying on TMC posts, the value of an R&D test program. Both:
1) empirical testing via Auto Racing
Real World Knowledge. Take Ford Motor Co, they used to have a SVO/Special Vehicle Operations headed by Michael Kranefuss. I last met him in '93, at the Long Beach Grand Prix, when Robby Gordon (offroad racing phenome) was racing for AJ Foyt. All the big names in Automotive (Honda, BMW, Renault, Mercedes-Benz, Toyota, et al) are involved with auto racing, especially Formula 1. It PAYS to race, not just marketing for brand-name-recognition, but "real world" knowledge learned on the race-track.
2) analytical approach, via Simulation (Monte Carlo methods, FEM/Finite Element Method)
Book Knowledge. Engineering & Applied Science is what Caltech calls it. 1 of Caltech's Mechanical Eng profs is on leave to Northrop-Grumman, to explore the Aerospace + Alternative Energy paradigm. All the expertise developed in Aerospace, can be applied to Green Tech. I'm recently in touch with 1 of my Dad's PhD students, who is very high up in Northrop-Grumman. I need to have a meeting with Martin, to discuss an Interdisciplinary Cooperative/Collaborative R&D Program (bridging the gap between Academia & Industry, & also cross-disciplinary cross pollination). This WILL happen (my own initiative), I'm writing a proposal for it right now. I had some really excited discussions at the recent SIGGRAPH 2008 conference, incl a German engineering prof associated with Fraunhofer Inst (known for pro-active investigation of engineering problems). Since Telsa Motors is opening the European markets (incl Germany), this sounds like a real opportunity. Whether Martin wants to be part of it, is another question.
2) is my Dad's specialty, he was AAE/Aeronautical & Astronautical Eng prof @UIUC (in the same building Coordinated Science Laboratory, when Martin was a summer intern '81 at our AARG/Advanced Automation Research Group). He hired Dr. Michael Selig (wind tunnel aerodynamicist, who also dabbles in analytical approaches like Genetic Algorithms), who consulted for Newman-Haas for 6 races (got Michael Andretti 3 wins). Alan Cocconi used a Selig airfoil, for his 2005 aviation project. Last I heard (2006), he is involved with a similar project & doing mountain biking in Utah (he drives a Subaru wagon..what else!)
I've been in touch with some Academics, SDSU & Caltech. The Caltech guy (Dept Head, Nonlinear Dynamics & Control) had 1 of his students end up at Williams F1. The other guy, is the main Academic contact for Formula 1. He almost left Academia to work for a F1 team. The top F1 teams have annual budgets of 200 million. Xtrac is heavily involved with various motorsports (Formula 1, Rally Racing). CORR (Championship Offroad Racing) is a new startup (you might have seen the LIVE TV coverage on Sat or Sun, on NBC), where Xtrac has some Pro 2 clients. I know both of these teams well. If Xtrac solved XXXX (for Desert Racing), I expect similar success for these 2 teams (in Short Course Racing). This knowledge, might have a cross-over effect to Tesla Motors pavement application.
That's why I'm advocating an Interdisciplinary Collaborative/Cooperative R&D Program (bridging the gap between Academia & Industry, & also disciplines).
End of Lecture.
You can see Xtrac (Andrew Heard) at:
BITD Las Vegas 300
[ he is incorrectly labelled at Eric Heard ]
BITD Parker 425: Contingency
[ that's none other than Robby Gordon of NASCAR fame, checking out Xtrac transmissions. This is the offroad equivalent of a tranny, which has severe shock loads: airborne cars land, creating stress ]
Last edited by a moderator: