Sent: Friday, June 23, 1998 Subject: [B*E*S*T] E-Car Race 1998 Part 2 -- Race Day Saturday, May 16th: Race Day. Friday's tornadoes gave way to beautiful blue skies. Windy, but with the temperature in the mid 70's. If you don't like the weather in the midwest, just wait a minute! I had brought home 8 batteries to charge for the race. Two were fully charged when I lost power around 4:30pm on Friday. I wired all 8 in parallel and hooked them to a 12v charger overnight, hoping the power would come on to finish the job. It didn't. The power was still off Saturday morning (and stayed off for 3 days :-( But the charge had equalized between batteries (12.8-13.0v) so everyone would have the same amount of juice. I arrived at the Armstrong High School athletic field track at 9am, and distributed the batteries. All teams were present, and making last minute adjustments and modifications to pass inspection. Donning my official "Mad Scientists Union, Local 3.14..." lab coat and clip board, the inspections began. Our checklist had been passed out to the teams well before the race, so they knew what to expect. Our requirements were pretty basic: 1. Is the steering system satisfactory? 2. Does it have working brakes? (If not, they have to carry a cement block tied to the car with a rope) 3. Is the car propelled only by battery energy? (no pedals or rocket engines) 4. Is the cockpit safe and have a seatbelt? 5. Are there any sharp edges or corners? (otherwise, get out the duct tape) 6. Do moving parts have guards? (will it pass the hot dog test, i.e. not cut a hot dog in two)? 7. Is it strong enough to carry a 200 lbs adult (Hey, we gotta have some fun, too) 8. Is the assigned battery being used, and securely mounted? 9. Is the battery and wiring protected from shorting? 10. Is there an easily accessible On/Off switch? 11. Does all power flow through the 30 amp circuit breaker? 12. Are there any other hazards? Compliance was generally very good. Some cars had more pointy edges than a Swiss army knife. Duct tape cured that. One team had to improvise a chain guard. There was a snafu because Armitage's engineer mentor had told his team they didn't need a seat belt, and the design made adding one impractical. The Morris Park car had an unfamiliar device for the circuit breaker. Neither their mentor nor the kids who had wired it were there, so nobody had a clue as to what it was or how to fix it. We tore it out and installed the specified circuit breaker. Then the car didn't work. Their mentor, K.C.Jones, arrived about this time, and some lively discussions ensued. But he was able to get the car going. We were worried about identifying the cars during the race. Many had no good place to put a number so officials could keep them straight. So we gave each team a number and a different color bicycle flag. Armatage's car had nice flat sides, so they left off the flag in the interests of streamlining. So our starting line-up consisted of: #1 - "The Car", built by Armatage Elementary's 5th grade class teacher Mike Farnsworth, engineer Bob Aske #2 - "254", built by Michael Dowling School's 5th grade class teacher Joe Rossow, engineer Lee Hart #3 - "Speedy", by Michael Dowling School's 6th grade class teacher Joe Rossow, engineer Lee Hart #4 - "Turbo Turtle" by Jefferson Elementary School's 5th grade class teacher Doug Fielder, engineer Eric Viken #5 - "BMW" (Bad Morris Windfighter) by Morris Park Elementary's 4th graders teacher Susan Seyer, engineer K.C. Jones #6 - "Tonka 2000" by Scenic Heights Elementary's 4th grade class teacher Jan Sellman, engineer Clarence Ogburn #7 - "Dragonslayer" by Sonnesyn Elementary's 5th grade class teacher Eileen Johansen, engineer Rick Cash Two cars from last year's race were on display, but hadn't been worked on since last year. Sonnesyn's "Stinger" was missing a drive pulley. But the Morris Park students decided to fix their "Road Runner" on the spot, and struggled madly to keep the motor pulleys from slipping and fix the "fuddled up wiring", as one student put it. They succeeded in getting it going, and took a couple parade laps around the track to celebrate. The Drag Race Our first event was a 100 yard drag race. We ran it as two heats. Half the cars competed in the first heat, half in the second, and the winners of each raced to determine the overall winner. In the first heat, "The Car" showed its stuff. With the lugs of its friction drive pulley thudding on the tires, it took an early lead and held it to win with an impressive 24 second run. "Turbo Turtle" took second. It started slow, but picked up speed right up to the finish line -- and then kept going! The driver had forgotten about the brakes and on/off switch, and was trying to stop with her feet. A convenient fence brought her to a safe stop. "254" came in third. It got off to a slow start -- and stayed slow. The driver forgot to turn on the second motor. The team's shouted advice was heard, but alas, too late. 254's time was good, but not good enough. And "Speedy" cruised to a steady 4th place; its low gearing for efficiency being outmatched for a drag race. In the second heat, "Tonka 2000" took the early lead, zipping along with a cheerful "squeaky-squeaky" sound. But "Dragonslayer" slowly picked up speed and passed it by the halfway point to win with a 25 second elapsed time. "BMW" came in third, with something rubbing. The crew wheeled it back to the pits where it was surrounded by tool-wielding team members. In the final heat, it was "The Car" vs. "Dragonslayer". Side by side they raced, never even a car length apart. The crowd was going crazy. But it was "The Car" in a near photo-finish. Their winning time was another 24 second run, with "Dragonslayer" just a fraction of a second behind. "The Car" engineer Bob Aske said all that saved them was leaving off that bicycle flag. The Autocross The second event was an autocross to judge maneuverability. Cones were placed every 5 yards along a 100 yard course. The cars were raced one at a time, and had to weave between the cones, turn around at the end, and weave between the cones back to the starting line. Fastest time determined the winner. A 5 second penalty was added for each cone missed or hit. "Turbo Turtle" made a good start, but suffered a breakdown, and did not finish. "Dragonslayer" was built like a rail dragster; long and geared for speed. It was barely able to maneuver between the cones, and needed help to turn around at the end. This combined with the slow accelleration to give them a 264 second run. "BMW's" team had barely completed their car the day before, and had almost no practice time. A couple of missed cones were the consequence, and something was still rubbing. But they completed the course in 243 seconds. "254" really flew through the autocross. The driver delighted/terrified the crowd (depending on their age) with his daring 2-wheel turns around the cones. But then trouble! A bolt fell off the rear wheel sprocket, allowing it to wobble, and the chain fell off. They put it on, continued, and it fell off again. Fixed again, and they finished the race (better late than never) at 224 seconds. "Speedy" took the course at a leisurely pace. Low, wide, and maneuverable, it had no problems, and took third place with a 219 second run. "Tonka 2000" again put in a steady, solid run. Their lower gearing was ideal for the twisty course. But a popped circuit breaker at the halfway point brought them to a momentary stop. It was quickly reset, giving them second place at 120 seconds. "The Car's" 12-foot turning circle barely allowed it to turn around in the track's width. But they had been practicing for weeks, and it showed. They made a flawless 80.5 second run, to take first place. The Endurance Run The final event was the 1-hour endurance race. The cars all raced around the 1/4-mile track for 1 hour. They had to stop and change drivers after each lap (to give each team member a chance to drive). Most laps wins. Each team's pit area was a 20 ft. stretch along the outside of the front straightaway. Each car started and changed drivers from its pit area, providing a reasonably safe distance between cars. Our rules were that drivers were to stay toward the inside, and faster cars had to pass on the outside. Any bumping or hitting would get a 1-lap penalty. The cars lined up just by their pit areas. Each driver held a hand in the air, Indy fashion, and at the starting signal they switched on their motors and were off! "Dragonslayer" was the fastest, and took the lead. But on lap 3, it came to a sudden stop. The shaft had snapped off their motor! It was pushed back to the pits, where the crew worked feverishly to replace it. "The Car" took over the lead, followed by "254" in second, and "Turbo Turtle" in third. The next car to retire was "BMW". They were still having problems with something binding, and decided to replace their motor, too. Streamlining shouldn't matter at 10 mph. But the wind had picked up to a good 20-25 mph. Sailing into the breeze on the front straightaway, flags flapping furiously with their masts bent back, the cars gave the crowd an awesome illusion of speed. But the high-geared cars had half the speed into the wind as in the downwind leg. "Turbo Turtle" was having a particularly difficult problem with this. They would slow to a crawl into the wind, and the motor was getting too hot to touch. They hit upon putting an ice pack on the motor (a plastic container with frozen slush in it from someone's ice chest). Other teams began to notice overheating, too. "The Car" got a plastic sandwich bag with icewater. "Tonka 2000" made their ice bag out of plastic wrap and duct tape. "254" was sometimes fast, and sometimes slow. They figured out that their two motors were overheating, and one of them had a thermal protector that kept switching it off and on. They took to drizzling water directly on their motors to keep going. At 25 minutes, "Dragonslayer" was back in the race, and moving fast to make up for lost time. They too had figured out that water cooling was the secret to keeping their motor alive. "Turbo Turtle" decided to pit, and change ratios. They had a double reduction chain drive with a 5-sprocket hub from a 10-speed bike as the idler. But it had to be disassembled to manually move the chain to another sprocket. "BMW" finally got going, and back in the race. But one lap later they were out again, this time for good. They retired with 2 laps completed. Only "Speedy" was immune from frying motor syndrome, having two motors and a sedate speed. They finished the 1-hour race with 7 laps to their credit. "Turbo Turtle" had to pit again. The rear bicycle wheel, which was supported only one one side, was wobbling badly. There was no time to fix it, so they nursed it on to finish the race with 12 laps. At the end of the hour, "254" had lost its overheating motor completely. They finished the race on one motor with 12 laps to their credit. With just 5 minutes to go, "Dragonslayer" again coasted to a stop with smoke pouring from its motor. There was no time for repairs, so they ended the event with 14 laps to their credit, taking third place. "Tonka 2000" just kept plugging away, slower but without any time consuming pits stops for repairs. They finished race with 20 laps to take second. And once again, it was "The Car" in first place, with 29 laps. Getting the car done early, testing, and practice had paid off with 3 first place finishes! Awards These races are not about speed; they are all about learning by doing, teamwork, and ingenuity. The following awards were presented: Award School Winner ----- ------ ------- Top Performer Armatage #1 - The Car Best Design Armatage #1 - The Car Most Original Dowling #2 - 254 Hardest Workers Sonnesyn #7 - Dragonslayer Team Spirit Dowling #3 - Speedy Most Promising Morris Park #5 - BMW Best Teamwork Jefferson #4 - Turbo Turtle Best Use of Materials: Scenic Heights #6 - Tonka 2000 Conclusion Words fail me in expressing the level of enthusiasm the kids had for this project. On race day we had a crowd of 300-400 people. Teacher Mike Farnsworth said he had 100% attendance; students AND parents. A neighbor called the police for excessive noise (at a high school football field?)! Teacher Susan Seyer called it "healthy madness." The kids call her classroom "Sanford & Sons" because of all the junk. There was an extreme reduction in fear of math and science. One student wrote, "I used to think electricity was scary and dangerous; now I think it is dangerous and FUN!" We have 5th graders arguing about ergonomics and parasitic weight. Chronic truants that have had perfect attendance. Students with learning disabilities that turned in every assignment on time. Will we do it again next year? Mike Farnsworth said it best: "We have to -- the parents won't let us quit!" If you want to see pictures of the cars and learn more about B*E*S*T, come visit us on our web page at http://www.pclink.com/best Lee Hart