Speed loop (ACRO mode — surge channel)
r_u(t) speed setpoint
Rate limiter ATC_ACCEL_MAX
Σ
+
−
LPF (error) ATC_SPEED_FLTE
PID ATC_SPEED_P ATC_SPEED_I ATC_SPEED_D
Σ
ATC_SPEED_FF (feedforward)
Surge plant (boat dynamics)
u(t) measured speed
Yaw-rate loop (ACRO mode — steering channel)
r_r(t) yaw-rate setpoint
Rate limiter ATC_STR_ACC_MAX
Σ
+
−
LPF (error) ATC_STR_RAT_FLTE
PID ATC_STR_RAT_P ATC_STR_RAT_I ATC_STR_RAT_D
Σ
ATC_STR_RAT_FF (feedforward)
Yaw plant (boat dynamics)
r(t) measured yaw rate