Motor max speed in Roborun

6 years 3 months ago #29529250 by dimracer
I'm tuning the SBL1360 controller in Roborun utility. What does actually mean the "MAX SPEED (RPM)" parameter? When I change it from 1000 to 6000 nothing actually is changed. Motor spins with 3000 rpm max speed and it doesn't depend on this parameter. How can I change max speed of the motor?
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6 years 3 months ago #29529252 by Griffin Baker
Replied by Griffin Baker on topic Motor max speed in Roborun
Max speed RPM parameter can mean different things depending on which operating mode your motor output is set to. In open loop, the command +1000 or -1000 will be the max speed regardless of what that value is set to. The change over in time that it takes to accelerate or decelerate is dependent on the max speed / accel or decel.

In a closed loop speed mode, the max speed RPM, is the max speed of the motor at +1000 or -1000. Any value in between will be less than the max speed. If the motor max speed is rated for 5000 RPMs, and you set the max speed rpm to 2500, then the controller will tell the motor that the max speed the motor can go is 2500 rpm in both directions.

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6 years 3 months ago #29529256 by dimracer
Replied by dimracer on topic Motor max speed in Roborun
The motor connected to controller is rated to 4000 rpm. And I set this parameter to 4000 in sbl1360. Controller configured in speed closed loop and in open loop. But when setpoint is max (1000) the motor speed is 3000 rpm. Then I changed max speed parameter to 1000. But the motor max speed is still 3000 rpm. Looks like there is a bug in sbl1360 controller. How can I fix it? I'm using the latest firmware v1.3.

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6 years 3 months ago #29529257 by Griffin Baker
Replied by Griffin Baker on topic Motor max speed in Roborun
Please upload your controller configuration profile in a zipped folder so it will upload here.

Roborun+ -> Configuration tab -> Save profile to disk

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6 years 3 months ago #29529258 by Griffin Baker
Replied by Griffin Baker on topic Motor max speed in Roborun
Did you set your feedback sensor to "hall sensor" or "other". The default is "Other" in which case you are using an encoder.

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6 years 3 months ago #29529259 by Griffin Baker
Replied by Griffin Baker on topic Motor max speed in Roborun
I've just tested closed loop speed with our SBL1360 controller using the latest firmware. Date code 3/11/14. You can get this in the console tab by sending in

?fid

I've adjusted my gain on my pid to the following.

P=0
I=1
D=0
Loop error detection: disabled

In the run tab, I set a channel for hall speed rpm.

The only thing I adjusted was just the max speed RPM. I have a 3500 RPM motor.

I left the default of max speed 1000 RPM and using the slider in the run tab, the utility reported back a max speed of 1000 RPM.

I then changed it to 2000 rpm max speed, and I was able to see it go to max speed of 2000 rpm's.

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6 years 3 months ago #29529262 by dimracer
Replied by dimracer on topic Motor max speed in Roborun
I tuned the max speed value in position abs tracking mode. First, I've set 4000 rpm. But motor spins with 3000 rpm speed max. Next I've set it to 2000 and then to 1000 but the motor spins with 3000 rpm speed. Here is profile attached.
Also I tried to change acceleration and deceleration parameters. But I didn't get any result. I've reset the controller to default parameters and then save new parameters in it. No effect. Only when I changed the accelration rate to 100 rpm/s the motor became start slower.
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6 years 3 months ago #29529263 by Griffin Baker
Replied by Griffin Baker on topic Motor max speed in Roborun
In the closed loop position tracking mode, it is because you are changing the rate at which the motor will accelerate. If you want it slow, then you set a lower acceleration and a higher max speed rpm. If you want a faster acceleration, then you do the opposite. Closed loop position tracking does not care about speed. It is about getting from point A to Point B as fast as possible and hold the position.

In your case, by setting the acceleration to 100 rpm's means that there is a much slower acceleration rate.

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6 years 3 months ago #29529266 by dimracer
Replied by dimracer on topic Motor max speed in Roborun
So, let me resume. MAX SPEED params work only in closed loop speed control. ACCEL & DEACCEL work only in open and closed loop speed modes. MAX VEL param works only in relative position mode. Am I right?
And what the real max speed the sbl1360 board can produce? As I can see it is 3000 rpm.

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6 years 3 months ago #29529268 by Griffin Baker
Replied by Griffin Baker on topic Motor max speed in Roborun
Max speed in closed loop mode means the actual max speed of the motor. In other modes, it is not the actual max speed of the motor.

Accel and decel work in all modes. They work differently in each mode.

There is no max speed that the controller can produce. It is dependent upon what is used to measure it. Hall sensors, or a higher resolution encoder.

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