PF Manual Tuning
From DIDEAS Wiki
How to perform manual tunning on the PowerFoot
- Commands are case sensitive! Shift indicates an upper case command
- Initialize Telemetry
- From wifi_fast.py command window, enter F4 to unlock screens
- Check nominal (pyramid) torque setting:
- Have user hold foot up in the air (level)
- Go to sensors screen (enter 3)
- Enter Shift C to zero torque
- Note may need to zero torque after tuning due to drift.
- If foot is not level, change virtual spring setpoint/offset
- Have user hold foot up in the air (level)
- s moves backwards (increases angle)
- x moves fwd (decreases angle)
- Check Matlab qIq screen to insure motor current is still near zero
- Enter Shift Z to set the zero position
- Go to std screen (enter "0")
- Early stance adjustment (ES: in command window. Early_stance_impedance_k,b in exported parameters)
- Stiffness (Heel Strike)
- s increases stiffness, x decreases stiffness
- Damping
- d increases damping, c decreases damping
- Note If foot comes down too slow, increase damping
- Stiffness (Heel Strike)
- Late Stance adjustment (LS: in command window. Late_stance_imp_k in exported parameters)
- Stiffness
- f increases, v decreases
- Note This is the K3 or "virtual spring". During dorsiflexion, loading spring. If "too light", or falling, make stiffer.
- Note Slow walking K needs to be more stiff, fast walking K needs to be less stiff
- Stiffness
- Set Peak Pyramid Torque Threshold (PCI: or power_curve_intercep in exported parameters)
- Shift R increases, Shift F decreases
- Have the user make some typical steps
- Set the PCI value to the users typical torque value (on Matlab plots torque)
- PFF Power Plantar Flexion (PFF: or pff_torque_gain in exported parameters)
- Shift I increases, Shift K decreases
- Watch Matlab tau pff screen
- Note Increases very quickly! Make small increases while walking
- Note Start at ~70, listen for regular motor activation