A more knowledgeable person than myself recently told me that the Neo motors had eliminated the need for a shifting gear box in his opinion. This had to do with its different acceleration and torque I believe. Does this make any sense and has anyone else observed the same?
I would never make that blanket statement. What type of drivetrain will be used? What is the friction coefficient of the wheels? Are your gear ratio and torque low enough to break your wheels free in a pushing match? Perhaps you want to use two neos, not 3 per side. Then all these answers might change again.
They have much torque at low rpm.
Would still get better with a transmission, but really impressive anyway.
I would say that when FIRST changed the limit on CIMs to be greater than 4 we truly saw the beginning of the demise of the shifting gearbox for the purposes of driving performance in FRC. Traditionally very few teams have utilized their shifters well. Robust automated shifting was and has been a rarity. Training drivers to shift properly, in the correct situation is not an easy task.
The last two years 1747 has utilized a drive with AM’s Redline motors (generally 8 motors, but we’ve tested 6). Putting this much power into the drive has resulted in what has largely been a no-compromise chassis from our perspective. It weighs less, goes faster, accelerates more quickly, is less failure prone, runs auto paths more reliably, and takes up less real estate on the robot than a comparably specified shifting drive.
You could achieve the same or similar results by dedicating more motors to your drive, regardless of the motor as long as you’re increasing the total power of the drive and being intelligent in your gearing selection. This is not only true of the 775Pro / Redline Drives, but also Neos, Mini Cims, and even Cims.
Spend some time with the JVN mechanical design calculator and see what you can come up with. I would strongly suggest a traction limited drive for the purposes of FRC competition game play though (meaning your robot has the capacity to break traction before your drive motors are stalled).
We went with a single speed transmission (driven by NEOs) this year for the first time in quite a few years. No regrets, has worked really well. Plenty of speed and no problems shoving folks out of the way.
I am not sure there has ever been a need to shift for the majority of teams since CIM motors made their way onto the legal motor list.
I suppose it depends on what you used the gearbox for. If you’re using the gearbox for efficient acceleration, then yes, you could probably just use a single-speed with NEOs due to their far better acceleration curves. If you’re using the gearbox so you have a low gear for pushing and a high gear for speed, then probably not.
That said, drive gearboxes aren’t the only thing that the NEOs impact, we discovered that the 3:1 VersaPlanetary + 775 motor we were using on our Cargo intake prototype could be replaced by a single direct drive NEO, saving about 0.5lbs and maintaining roughly the same performance.
How many Neos?
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