Difficulty Tuning HFI on Hoverboard Motor for Low-Speed, High-Torque Application

Hello VESC Community,

I am trying to configure HFI on a hoverboard motor using a VESC6 MKVI for an application requiring extremely smooth startup with low speed and high torque. Despite following the video tutorial for HFI tuning, I am encountering challenges specific to this motor. Here are the details:

Motor Specifications:

• Resistance: 177.1 mOhms
• Inductance: 445 µH
• Ld-Lq: 222 µH
• Flux Linkage: 768 mWb

Current Settings:

• Kp: 0.45
• Ki: 175
• Observer Gain: 1

Observations:

1. Successful HFI tuning on a different motor: Using the same tutorial, I successfully tuned HFI on another motor without issues. However, with this hoverboard motor, I get scattered data points instead of grouped measurement points during tuning.
2. Hall sensors: The motor has Hall sensors, but their precision seems insufficient for smooth low-speed operation.
3. HFI potential: After watching Benjamin's "0 Speed Full Torque" video, I believe HFI or Silent HFI could work for this setup.
4. Encoder possibility: I’m considering trying an encoder for better precision but would like to understand if HFI can still be configured properly for this motor.

Request for Assistance:

1. Is there a way to improve the grouping of data points during HFI tuning for this motor?
2. Could the specific motor characteristics (resistance, inductance, etc.) affect the HFI performance, and if so, how can I adjust the parameters?
3. Are there additional tweaks I can apply to make Hall sensors more effective, or should I proceed with the encoder directly?
4. Any tips on silent HFI configuration for such a motor?

Any help or guidance would be greatly appreciated!

Thank you in advance.