The minion motor

I still do not really understand the benifits of the minion motor.
The minion motor costs 70$, and the motor controller costs 120$, which is basically the same price as a kraken motor.
So what does the minion motor have that the kraken not have

tiny

the minion is good cuz its small, its meant to “compete” with the x44 and neo 550

Being a standalone brushless motor, I don’t think it’ll be too difficult to use it with a SparkMAX or Nova.
It’s more of a drop-in replacement for teams using the NEO 550 than the Kraken X44 is.

1 Like

But those are the same price (the x44 and minion motor)

If you’re buying both a new motor and motor controller, the X44 seems to be the better option than an FXS + Minion, and their prices are roughly the same. Buying just the Minion and using it with a SparkMax you already have is much cheaper than buying an X44.

9 Likes

Drop in for what? It’s not a 550 shaft.

1 Like

More of a drop in replacement than the X44. Not a perfect fit though

External motor controller. It allows the motor to be packaging in less length length than the X44, and the talon fxs can have an encoder directly attached to it reducing a device on the canbus and saving the insane cost of can encoders. Along with also being able to replace the motor without the controller if you burn one out, which is easier to do on low thermal mass motors.

Whether this matters to you is a different question, but it really is a sidegrade to the x44 where the difference is integrated controller or not.

5 Likes

It’s very much about the size and it being an alternative to the Neo550. It’s not a direct drop-in replacement, nor should it be. There are too many things about the older 550 models (brushed or brushless) that needed fixing. The shafts, to begin with, have always been too small for the purposes to which we might like to put the motors (especially Neo550s with their much increased power over traditional 550 motors.) Now CTRE and WCP have standardized on one shaft configuration across three motor sizes (Kraken x60 = CIM, Kraken X44 = 775, Minion = 550) which makes everything else much more standardized too (gears, pulleys, whatever.) The Minion also has a phenomenal amount of power for such a small motor, making it the new go-to for things like OTB intakes, where size and weight are a factor but you really want some serious power. On the operations front, they will hopefully be (in true CTRE/WCP tradition) more reliable than Neo550s have been so far. Finally, it completes the CTRE ecosystem of motors that those of us who like what they do have been hoping for.

5 Likes

There is an interesting cost advantage to using the minions as a steering motor for swerve. The TalonFXS allows to use the CTRE Mag encoder for steering, which is $40 as opposed to the $90 CANcoder. So $50/module, $200/per robot is significant.

That said, I wonder if teams will find success using a redline or 775 pro for steering powered by the TalonFXS, which would save another $50/module.

Based on other threads, I believe all of these configurations would be supported by the CTRE swerve library.

5 Likes

Regarding the neo 550s, the main issues we had were:

(1) Broken encoder wires – just too fragile
(2) smoked a few

On the other hand, it was great to be able to use them with our versaplanetary gearboxes.

2 Likes

It can work, but the small brushless motors are a large upgrade over brushed 775 motors in that they have a much higher kT and kB, meaning you need less gearing for useful torque, are significantly more efficient which helps on the battery, have better thermal characteristics due to generating less heat and being able to directly dissipate heat by only generating heat in the stator, and are significantly lighter and smaller.

In contrast, a cancoder gets you nothing over a non-can encoder, as all they do is measure the position of something and I can’t imagine them having significantly different latency noise.

I will say, the weight of the Minion motor isn’t public yet. While it’s probably going to be pretty light, technically nothing stopping it from being a hunk of lead :stuck_out_tongue:

1 Like

All that’s true, but don’t think the loss from a steering motor is all that significant. A Redline is still significantly overpowered for that application. There are lots of places that I want a brushless motor, but I’m not sure that it’s really that needed.

You will need more reduction. It doesn’t make sense for “large” modules like SDS, but I think it would be adequate for the SwerveXS/X2S line. Maybe even in the Rev MAXswerve line if you can find a brushed 550.

It’ll also very likely leave you scrambling to have a working robot for this season, so if you’re into that and regularly calling CTRE about your order, it seems like a really good option rn.

9 Likes

Technically, lead lacks the magnetic permeability or electrical conductivity to be a useful motor material. I’ll keep using iron and copper, until better materials are engineered. Probably that will happen later this century.

RC and the engineering team might still be working on the trade off between making the Minion lighter vs. making it more thermally robust, but I can assure you that lead won’t help with either of those goals.

Just to be clear, the Minion is CTRE’s motor. WCP is not involved in its development, we are just a distributor for it and the TalonFXS.

We are directly involved in the development of the Kraken X44 along with CTRE.

3 Likes

I think it would benefit both companies to be much more clear about that, especially when they’re selling each others’ products and creating products that use some technology from the other company.
For anecdotal evidence, I didn’t know that CTRE and VEX were two separate companies (I thought they were brands/divisions within the same company) until part of the way through my junior year.

1 Like