Question about resistance modeling in motor parameter identification

[idleno]

Describe the Feature

Hi! I have a question about the parameter identification process in Appendix 8.9 (Motor Test Bed).

In the damping and friction loss identification section, the resistance is modeled as comprising both damping and friction components.

However, when calculating the initial stored energy during moment of inertia identification, the paper states:

"Using the previously measured damping values, the resistance power can be numerically integrated to estimate the initial stored energy E."

I'm curious why only damping is considered in this energy calculation, while friction appears to be excluded. I look forward to your clarification!

Use Case

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Alternatives Considered

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Additional Context

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[weizhuowang]

That sentence might be a bit confusing, but in practice(code) what we did to get energy was to directly integrate the resistance torque previously measured at each speed. So it contains everything that contributes to resistance, even in the future we model more terms to Tau_r equation, this will still be accurate. Therefore, to answer your question: we use damping and frictionloss to integrate to the energy E.

[idleno]

Thank you for your prompt and clear explanation regarding the energy calculation method. I really appreciate it.

I noticed that the system parameter identification section in the repository doesn't include the establishment of damping and other motor properties. Would it be possible to open-source the code for motor parameter identification?

I'm currently learning how to perform servo motor parameter identification and believe your methodology would be very valuable. Looking forward to learning an effective approach from your work.

[hshi74]

Have you checked out this tutorial?

[idleno]

Yes, I have checked it, especially run_sysID.py. I think you provide the code to mainly identify parameters like q_max, q_dot_tau_max, q_dot_max, ..., as well as damping, friction_loss, armature. However, my problem is related to that I don't see how damping, friction_loss, armature are initially calculated using the method described in the motor test bed section of your paper's appendix. In the code, I see that you initially define a range for these three values and then perform optimization within that range.

[hshi74]

I see, please give us some time to organize the materials of building the motor test stand and clean up the code. Feel free to send us a reminder here if we don't release them in two weeks. Thanks for your patience!

[idleno]

Hi, just a gentle reminder about the motor test stand materials and code cleanup—hope everything’s on track. Looking forward to your update when you’re ready.