The Vortex has the highest Free Speed at 6784 RPM and the Kraken X60 has the highest Stall Torque at 9.37 Nm with FOC. If you don’t want to pay for FOC, the Kraken X60 still has the highest Stall Torque with 7.09 Nm.
For the Shooter, I expected the NEO Vortex to win cause of its high Free Speed, same for Swerve but most people choose the Kraken X60 FOC which is fifth against the other motors on RPM but number 1 on Torque. Is Torque more important for Swerve than Free Speed? Even SDS’s page has the NEO Vortex being the fastest option
Of course, the poll could be skewed due to the current stock issue with some products and/or for what teams had in hand.
Overall, I am just trying to get a better understanding of the best use case for Free Speed and Torque.
What am I missing? Teach me, and potentially other Rookies that want to learn.
I think a lot of those poll responses would have come down to what motors teams have on hand at the moment and what motors they are expecting to receive from back orders.
I know we would love to be in a situation where we have a choice. In Australia we committed Falcons order numbers in Mid 2023 with a local supplier, only to be told in December that they weren’t going to come at all for the 2024 season.
This was after everyone had completely back ordered all the new motors out of existence.
I think every one should have to use sim motors and mag encoders to level up the playing field across the world.
Free speed can be exchanged for stall torque by changing the gear ratio of the mechanism the motor is attached to. Increasing the ratio multiplies the stall torque and divides the free speed by the same factor. What you should really care about is the motor’s max power, or (free speed)*(stall torque)/4. That will actually tell you how strong the motor is.
I would like to know, what would be the best motor for certain mechanisms, like swerve, arms, elevators, etc. I assume, as you said, it would be based on gear ratios.
Actually, again it’s a bit of a power question rather than a gear ratio question. And the correct answer is going to be “It Depends”.
Motors supply power, at a given speed and torque.
The gear ratio shifts the speed/torque values around to where they’re needed. Importantly, the gearing cannot add power–just different speed/torque values.
So, for example: I have an arm, 5’ long. I need it to move through 135 degrees in 3 seconds, while carrying a load of 10 lb at the far end. How do I figure out what motor(s) to use, and what to gear them for?
I know force, distance, and time. I also have a rotational speed of the arm, which can be used to check numbers. Work = force * distance (NOTE: for this you actually want the length of the arc traveled through, NOT the length of the arm), Power = Work/Time. Round up to the nearest legal motor or set of motors. Because we also have the arm length, we can find a minimum gear ratio for torque, and a maximum gear ratio for speed. If we need too much ratio, find a different motor set and try again.
The answer is: it depends. On a bunch of things. There’s no one right answer: engineering is all about making tradeoffs.
I do highly suggest you take a look at the AMBCalc mechanism calculator and the associated documentation to learn more about motors and gear reductions
