Simucube 2 pro slew rate

watching the reviews of the asetek wheelbases earlier and there is one reviewer stating that the simucube 2 pro wheelbase is 6.3nm/ms. i corrected him ofcourse and he is pretty confident i am wrong and he is right and he seems to indicate that the bases were tested by asetek and the 6.3nm/ms is what they tested the simucube 2 pro bases at.

im pretty confident that the specs stated by granite are correct but any idea why another manufacturer would claim otherwise?

Dave cam is not the sharpest knife in the drawer so I wouldn’t really listen to what he has to say

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Lol. I watched the boosted media review and he said that they are measuring in a different way

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:joy::joy::joy::joy::joy:
Didn’t know the expression…:joy::joy:

That is important to know, WTF is Slew Rate Limit and how the companies measure it

the measuring it question is one that confuses me also, surely the slew rate of the motor is one repeatable test… slew rate being the speed in which the motor can accelerate in a set amount of time, in theory the more nm/ms the faster the response and the more detail is exposed… in theory. hence why the simucube 2 ultimate is the top dog in this lineup of motors, being the fastest motor available.

It can be a marketing number from Asetek afterall, like the No Play QR

Max slew rate is not just how fast motor can accelerate, it’s limited by encoder resolution as it needs to keep a track of positioning.
http://what-when-how.com/electric-motors/slew-rate-electric-motors/
Also found this definition, it’s for stepper motors but the same general principle.

Maximum Slew Rate The maximum slew rate is the maximum velocity at which the unloaded stepper motor can remain synchronous with the command pulses under the specified drive conditions. This velocity is usually defined in the Full Step Mode of 1.8° steps or as shaft speed in revolutions per second.

As for measurement, I guess the spec was just given by a motor manufacturer, not measured in house. But that’s just my guess.

i see… i mean they use an encoder with the same resolution as the simucube 2 pro so its likely up to the task i assume, would be a disaster if the motor was so quick it lost tracking on position.

The motor is different though, they use custom manufactured Mige IIRC.

thats right yeh, ive actually ordered an invicta today so i can do a side by side and see whats up, in a way i want it to be the one i stick with as im feeling like the current simucube platform has stagnated a little and is being left behind, so much focus on one pedal while other manufacturers are knocking out wheels left right and centre… i do genuinly love the SC2 though, it will be extremely difficult to move away from the simucube knowing it has such proven reliability and has never really stepped a foot wrong with me but there is always that urge for something new.

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We have measured the slew rate and stand by the numbers.

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Can’t agree more. Please post your findings on how good it is on SW side in comparison.

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Please, test with the same wheel you are using on the SC2

i wont be able to do that because they are not currently selling the QR seperately, apprently soon though. if they release that before i get the wheelbase which is due in march then ill for sure do that, currently using a cube controls F pro but have ordered the forte wheel with the invicta to be sure i have something to use, its pretty bloody ugly though, hope it grows on me.

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thanks for that, i trust this.

Most everyone is at the high end are using the same Encoder basis (and actually the same part), SC2 Pro/Sport, VRS, and I am sure the Asetek one falls in this as well (EDIT: it does it uses the same BiSS 22bit the SC2Pro and Sport and the VRS does.)… Not sure on the Moza or Sim Magic, Fanatec is different… That being said between the SC2 and the Asetek (SC2 Tech) the calculations would be pretty much just Ramp-up Speed…

This being said DD’s are generally much to fast on ramp-up to provide a realistic driving experience (Crashing Experience Yes, Driving no). So a difference between 15Nm/s and 6Nm/s is probably not really going to change what you might actually want to feel at the wheel… in fact the 6Nm/s would more likely give you a more accurate to real life driving experience.

The Mis-Information is that Faster equates to more detail… It doesn’t there is as much detail as long as the initial response is on target… The thing that is limited is the Amplitude of that detail IF the Slew rate is slower than the signal change…

i.e Two servos are provided with a signal say of an 20Nm amplitude over a second and then return to zero. Servo #1 has a 6Nm/s Slew and Servo #2 has a 15Nm/s slew.

BOTH servos will start accelerating at the Same time… (This is the detail) However, Servo #1 will cap out at 6Nm before returning to zero while Servo #2 will cap out at 15Nm before returning to zero.

So lets add a signal… 20Nm @ 1Sec then 10Nm @ 1sec then zero.

Servo #1 would reach 6Nm in that first second then continue on to reach the 10Nm at a rate less than Slew since it only has 4Nm more to go then it will return to zero…

Servo #2 would reach 15Nm in the first second then have to reverse direction to get to the 10Nm at a lower rate than slew then go to zero…

In this case you could argue that you are losing the peak fidelity because the first servo would be still ramping up to force while Servo #2 is on its way back down… However, you are not actually Losing the detail in the signal because there is a response from the system to each point.

This could be considered a more analog method of signal smoothing that trying to do it digitally (you are letting the servo do the work) and it is VERY effective and you aren’t losing anything from the signal as far as detail.

Granted the Slew Filter is a digital method of doing this same thing.

My homie chat gpt told me this :smiley:

what is the max slew rate of the simucube 2 pro?

The Simucube 2 Pro is a high-end direct drive force feedback wheel for sim racing, and it has a very high maximum slew rate. Specifically, according to the manufacturer’s specifications, the Simucube 2 Pro is capable of producing a maximum slew rate of 40,000 degrees per second. This means that the wheel can turn at a very rapid rate, which is important for providing accurate and responsive force feedback to the driver during simulation racing.

It’s worth noting that the maximum slew rate is just one of several important factors that contribute to the overall performance of a force feedback wheel. Other factors include torque, resolution, and latency, among others. All of these factors work together to determine the overall feel and responsiveness of the wheel, and it’s important to consider all of them when choosing a force feedback wheel for sim racing.

And what is the slew rate measured in nm/ms

Slew rate is typically measured in degrees per second (°/s) rather than in units of force (such as Nm/ms). However, it’s possible to calculate the equivalent slew rate in terms of force if you know the torque and the time required to reach that torque.

For the Simucube 2 Pro, the maximum torque is listed as 25 Nm. Let’s assume that the time required to reach that torque is 10 milliseconds (ms), although this number could vary depending on the specific setup and settings.

To convert from degrees per second to force per millisecond, we can use the following formula:

Slew rate in Nm/ms = (slew rate in °/s) x (torque in Nm / 360) x (1/1000)

Using the maximum slew rate of 40,000 °/s and the maximum torque of 25 Nm, we get:

Slew rate in Nm/ms = (40,000 °/s) x (25 Nm / 360) x (1/1000) = 2.78 Nm/ms

So the equivalent slew rate in units of force would be approximately 2.78 Nm/ms.

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i think im following, i think :slight_smile: but appreciate the response either way, thanks.

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I think the AI interpreted slew rate as the angle. Which is correct. But what the discussion was about, is torque slew rate.

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