Franks Collins Hip Controller

Description

Provides Hip assistance based on a series of splines that have an extension and flexion portion. Uses percent gait, requiring heel FSR. Based on:

Franks, P. W., Bryan, G. M., Martin, R. M., Reyes, R., Lakmazaheri, A. C., & Collins, S. H. (2021). Comparing optimized exoskeleton assistance of the hip, knee, and ankle in single and multi-joint configurations. Wearable Technologies, 2.

Parameters

Parameter index order can be found in ControllerData.h.

• mass - User mass in kg used for denormalizing torque.

• trough_normalized_torque_Nm_kg - Largest extension torque normalized to user mass (Nm/kg).

• peak_normalized_torque_Nm_kg - Largest flexion torque normalized to user mass (Nm/kg).

• start_percent_gait - Percent gait to start the torque pattern so it doesn’t have a discontinuity at heel strike.

• trough_onset_percent_gait - Percent gait to start applying extension torque.

• trough_percent_gait - Percent gait to apply the largest extension torque.

• mid_time - Transition point between extension and flexion to apply 0 torque.

• mid_duration - The duration of the transition pause as a percent of the gait cycle.

• peak_percent_gait - Percent gait to apply the largest flexion torque.

• peak_offset_percent_gait - Percent gait to stop applying flexion torque.

• use_pid - This flag turns PID on(1) or off(0)

• p_gain - Proportional gain for closed loop controls

• i_gain - Integral gain for closed loop controls

• d_gain - Derivative gain for closed loop controls