Long Overdue Hybrid Tale
Formula-Hybrid 2008 - Loudon, NH - New Hampshire Motor Speedway. Here goes:
So, the engine I spent months on was tuned by someone who knows carburetors, and the oil reservoir was "topped-off" by a sparky. Most sparkies are purely electronics nerds and have no business anywhere near engines; this was one such sparky. Keep this in mind.
A week before competition, the engine was suffering from pretty severe overheating problems, and it was determined that our Magic Green Box (power electronics DC/DC converter) was actually controlling its output, not its input, so the engine load was wildly unstable. The ultra-robust control system that I designed in part in parallel with engine work was deemed useless. However, I didn't find out about this (life still happens around racecars) until the captains had already decided on a new control scheme and implemented it. The short version: the ultracap voltage charges proportional to engine speed. This means if the voltage is low, they will charge slower, and if voltage is high, they will charge very fast and overcharge becomes an issue. This is one of the stupidest things I've ever heard of in my life, but at least it kind of works...
DAY -2:1 - Two days before competition, we are working on safety inspection points, body work, and completely overlooking the design component of the competition, which is worth about a third of the points. So at midnight, the day before comp, I take a few pictures of the nearly-completed car, make a poster template, and throw together some ~accurate design posters. At 8 am I send three 24"x30" high-resolution posters to the color plotter in Thayer. We have a design presentation in Loudon, 80 miles away, at 11 am. The trailer leaves at 9:15 (an hour late, because the driver felt like sleeping in) with two of the posters, cut and mounted. I think we'll have to pass up on the third, go home and take a fast shower and get breakfast, and plan on driving myself out. When I get back to thayer, my friend Scott is printing directions to the speedway with his car outside and the poster is almost finished. We wait 5 more minutes, and jump in the car at 9:55. I closed my eyes and we got to the speedway and threw the poster on its easel at 10:58. Captain Donald ROCKED the presentation, and we made the finals.
DAY 1 - After lunch we went through the Electrical Tech Inspection and passed with flying colors, though you wouldn't have known it by the way the judges were throwing hypothetical dangerous situations and previously-seen disastrous situations (exploding snowmobiles, etc) in our faces for the entire HOUR they were picking over the car in our paddock. Bottom line? Fuses. LOTS and lots of fuses. Fuses with appropriate values. Then we pushed the car over to the Mechanical Inspection station where Paul's beautiful nose cone promptly failed the 3-inch radius test. We also needed to weld three more load-bearing sections into the frame, lower the headrest height because I'm so short, and make a few other minor adjustments (bolt sizes, etc). Each driver had to run through the quick-exit test; fully strapped into the car, with helmet, wrist restraints, and gloves, both feet must be on the ground outside of the car in under 5 seconds. With our catlike reflexes, none of us had any problem with this, even as under-rested as we were. We also put her on the scales, and Molly weighs in at a whopping 935 lbs. Fuel efficiency?? HA!
Concurrently - Donny and Calvin were looking pretty and spouting charisma, knowledge, ideas, and a sweet powerpoint slideshow at the judges for the marketing presentation, and grabbed us a first place for that event. We made our tech fixes, and were out by 8 pm. Some teams were there all night and STILL never passed inspection.
DAY 2 - First thing in the morning, we get our Mechanical Inspection sticker then get in a fight with the Noise judge because he wants to test our engine at 11,000 RPM but our engine doesn't go up to 11,000 RPM because we never sized up the jetting needles and we limit around 9,000 RPM. So he tests us at 8,000, and we pass without a problem. The engine was warm and I already had my fire suit on, so we went out to the track for the final inspection - the brake test. It took me three tries, because we had been incorrectly informed that our brake bias adjuster was backwards because it was too far forward, so when we tried to adjust them to the rear, they only went MORE forward. We took what fuel our tank would hold of our allotment, then got right back on the track for the 75m Acceleration event. I ran ~5.1s for electric only, then did a hybrid mode run in 5.019s. We had no idea how well this would hold up against other teams, since we were the first to pass all the tests and get on track but the spectators were loving it. The local news channel interviewed me, then posted the video article later spelling my name incorrectly and giving a horribly inaccurate explanation of how the car works. Check it. What I DIDN'T know is that there was a current limit on the electric motor controller, so I wasn't even at full potential. So Mr. Napoleon showed up in another fire suit after a few other schools had run and not come within a second of my WORST time having turned OFF the current limit, and spun the tires for 20 feet down the track until he picked up the traction and clocked 4.994s. I wanted to hit him. I don't spin tires. I rock high-torque. Its what I do. But the event was closing so I didn't get to try for 4.5. Maybe next year...
We had lunch, and took the car out to the practice track (which was really more of a crib made of parking cones and not big enough to be remotely useful), then wheeled it back over to the regular track, where Mr. Napoleon decided he would also drive the autocross event. He took off the line and immediately plowed smack into two cones. Around the halfway mark, the caps ran out of juice because he'd pushed it too fast for the stupid control system HE helped design and he had to sit on the track and wait to recharge. That was embarrassing. Then he did it again and made 55 seconds and only hit 1 cone. At LEAST there's that. They (I wasn't on the track for this one since we're only allowed to have 4 people from the team on the track at any given time) pulled the car back into the pits to tweak a few things with the steering, and I went to the bathroom, expecting them to tweak for at least 5 minutes. When I got back out, I hear that Paul has made both of his runs and in doing, got a cone stuck in the suspension, did a few donuts, and went off the track into the grass, and definitely drained the cap banks. Oops. I guess that's what driver training is for.... too bad we didn't do any.
Later that afternoon we geared up for the design finals, which was kind of a lost cause at that point, because the guys who had been there the day before (the mechies) who got us into the finals in the first place because they understood the systems that had been designed by last year's team - who were no longer around - weren't there that day. We read old reports and called old members and talked amongst ourselves, but not nearly enough. It also didn't help that while we were presenting, the comp-wide BBQ was going on on the other side of the infield and we were all starving. I think I answered two questions, tops, intelligently. He probably asked 50. Then we ate hot dogs and got in a cake fight.
DAY 3 - Endurance day. This is really the event that justifies the hybrid and proves that these are vehicles capable of both fuel economy, reliability, and performance. Two drivers and 22 km, worth half of the total competition points. Only 5 of the 11 cars entered in the competition have passed all of the inspections and are allowed to drive. Our other sparky drove first, and Donny, our fearless leader, was going to bring home the W. Unfortunately Tommy accidentally hit the electronic kill switch and the car won't restart as a hybrid without a palm pilot (which we didn't foresee being useful on-track) to clear the motor controller errors. The officials pushed him off the course and he, not really understanding the protocol for this situation and the officials being of NO help, got out of the car. We ran around like chickens with our heads cut off until we got some helpful information. He could drive the car back to the pits on pure electric, and they would decide LATER, since there was no rule set, if a driver exit constituted a disqualification. Five minutes later, he's back out on track, running smoothly, when the engine starts to smoke and the officials officially disqualify us for leaking oil. Two laps later the same thing happens to Embry-Riddle, our top competitor up to that point. Three laps after that, McGill finishes in under 40 minutes. Then we find out that we've (not surprisingly) taken 4th in the design competition (last in finals).
And that's how we took 4th place at the second annual hybrid competition, hosted by our own school, in our home state. But at least we had the best-looking team shirts. UVM won all of the design competitions and best hybrid concept stuff, but they had a totally awesome car with 4-wheel regen and Prius cells and a ton of other cool ideas that we just don't have the manpower to implement.
DAY 8 - Faculty advisors drain the engine oil and find that it is holding over 3 liters, when it is rated for 1.9. That's life, I guess. Maybe we'll do better in Italy in October when Donny and I fly her over to the Formula ATA competition and my personal life isn't in shambles.
Note to self: Facilitate prevention of shambles.
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