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experiment tab rpm ramp up and dual separate motor control

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tobiokanobi
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experiment tab rpm ramp up and dual separate motor control

Dear All, Dear VESC and Trampa support Team,

I've two Motors set up Coaxial Arranged. I can obviously control each of the two with separate VESCs and Tools, each running on a separate Laptop and USBs.

If I would connect them via CAN, does the experiment tool support to set different speeds of each motor? (So only one Laptopis needed).

Another thing, most likely the more important one:

When running on experiment tab rpm control big steps, then it's like really a hard switching from one setpoint to the next, causing quite inrush peak currents. And triggers early the current protection before actually the max rpm is reached. If I use very small steps then I can go much higher (but it takes endless).

Is there a way to ramp slower between steps?

Thanks (to the usual suspects who answers)

Tobias

tobiokanobi
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What I mean looks like this: Blue line is ramp up to end rpm; red line is ppm controlled

Exp_Tab_rpm_coax_setup_current_Spikes.jpg

Exp_Tab_current_coax_setup_current_Spikes.jpg

tobiokanobi
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Hi!

Has anyone an idea how to avoid those peaks during ramping up with the experimental tab?

Kind regards,

Tobias

tobiokanobi
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*I'm pushing one last time*

frank
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In the experiments tab you can not ramp slower. RPM control means you dial in a certain RPM and the VESC tries to reach that RPM as fast as possible. You could choose smaller steps.

At the moment you can not control/monitor two motors in VESC-Tool at the same time. You can control the units with CAN commands, using a CAN controller. You can log each VESC unit via the logging feature in VESC-Tool. Each motor needs to be connected to one VESC-Tool in that case.

 

tobiokanobi
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Thanks Frank!

My (in the next days) solution for the experiment tab is to ramp first to max RPM and then do it visa versa by ramping down. I expect that  the first inrush current does not fully peak so far up. I also tried it with "RPM control" in the left bottom corner, but at least in my case, it always switches after a few seconds of. 

Regarding two motors, independent speed; understood.

BTW while testing today PPM input two things jumped me on:

1) For whatever reason the VESC requires a few "applies" before it really switches and indicates the right mode. Sometimes the control/feedback indication seems to be a bit "jumpy" and don't show the real position. It needs a few time set, apply...to get it indicating right.(I've tried all modes, always with no brakes)

2) If you select on the first PPM input any mode and applied, and then switch to the "next step", the second window shows a different control mode (in my case it was always "current control with brake". I had to re-select on the second page again to get it working (and least for my satisfaction).

Have a good one!

Tobias