Scioly.org

sr243 wrote:This may sound dumb, but a 7.4 V hobby aircraft battery works right? We are buying it online and this type of battery is considered commercial, right? I only saw it mentioned once.

These batteries are certainly commercial batteries and would be allowed. You may want to check the actual voltage reading with a voltmeter to make sure it doesn't exceed 9V since these lithium batteries start much higher than their rate voltage.

JTMess wrote:

sr243 wrote:This may sound dumb, but a 7.4 V hobby aircraft battery works right? We are buying it online and this type of battery is considered commercial, right? I only saw it mentioned once.

These batteries are certainly commercial batteries and would be allowed. You may want to check the actual voltage reading with a voltmeter to make sure it doesn't exceed 9V since these lithium batteries start much higher than their rate voltage.

Always a good idea to check, but you should be okay. A lithium battery rated for 7.4V puts out about 8.4V when fully charged (4.2V per cell max, 3V per cell min).

JTMess wrote:We tried using two motors for a while and found that it was significantly more efficient to use one motor connected to two batteries wired in parallel.

++ no reason to add the weight of an extra motor.

sr243 wrote:This may sound dumb, but a 7.4 V hobby aircraft battery works right? We are buying it online and this type of battery is considered commercial, right? I only saw it mentioned once.

http://avogadro.ws/messageboard/viewtop ... 11&t=20165 answers your question authoritatively.

And as I've said on the helicopter thread, send me a message if you have any further questions and I can help you with a lot more information, some of which I don't want to disclose publicly.

Flavorflav wrote:It wasn't 0.6 seconds. It was under 1, but not by much. Tales grow in the telling, as they say.

Do you know what the weight of the sled was?

What would be the best motor-fan combination?

I am not exactly sure what you mean by that, but in general, you really only want one motor with a good propellor designed to give maximum thrust. Adding the secondmotor is usually not worth it; in fact, the air currents from the two propellorscould easily conflict, actually hurting your vehicle's performance.

Do the rules allow for computer-like parts such as a speed controller? We are attempting a set-up using a car that is remotely controlled through a speed controller. Although it doesn't seem like rc cars would be allowed, we didn't find anything in the rules that specifically banned it. Thanks for any opinions you may have!

Is the "sled" provided by the event supers or are we responsible to bring a sled?

baker wrote:Is the "sled" provided by the event supers or are we responsible to bring a sled?

The sled will be provided at the state competition. There will be two tracks with the same width on both. Teams will be allowed to balance and adjust cars, slide them back and forth with sled attached to create the best flow of movement, all within the time provided. Prior to the run, students will NOT be allowed to turn cars on, as this will influence prediction times.