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Unread 03-05-2014, 03:22
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asid61 asid61 is offline
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AKA: Anand Rajamani
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Re: 4-speed gear automatic gearbox

Quote:
Originally Posted by cj3958 View Post
I think one aspect of the 4 speed transmission that people are leaving out is that if you have 4 speeds, your motor will always be running under either peak efficiency or peak power output depending on what you want to do(for this idea, I am assuming that automatic shifting was developed). If the CIM was always running at peak power, then you could essentially have more watt's pushing than the opposing team, assuming you both have 4 cim drive-trains and that the opposing team has a 2 speed transmission, because your motors would be putting more of the electrical energy into pushing power, and more of the opposing team's electrical energy went into making the motor hot, you would have more watts of mechanical energy pushing on the ground which is what you really care about, not how many watts the motor says it has. I am not saying it necessarily justifies the resources needed to create said gearbox, but I just thought it was worth putting out. I am just a student on my team however, so correct me if I am mistaken in my logic or whatever this is.
There's no point in pushing the motors with 4 speeds instead of two, because although you can get the motors to operate at peak efficiency that means nothing due to the low match times. Plus, at a low speeds (~<8fps) drives become limited by their traction, not by their power.
Efficiency is an interesting point, but I'm not sure it would help enough to justify the extra weight and double-shift problems.