You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
97 lines
3.2 KiB
97 lines
3.2 KiB
import numpy as np
|
|
from selfdrive.controls.lib.drive_helpers import get_steer_max
|
|
from common.numpy_fast import clip
|
|
from common.realtime import DT_CTRL
|
|
from cereal import log
|
|
|
|
|
|
class LatControlLQR():
|
|
def __init__(self, CP):
|
|
self.scale = CP.lateralTuning.lqr.scale
|
|
self.ki = CP.lateralTuning.lqr.ki
|
|
|
|
self.A = np.array(CP.lateralTuning.lqr.a).reshape((2,2))
|
|
self.B = np.array(CP.lateralTuning.lqr.b).reshape((2,1))
|
|
self.C = np.array(CP.lateralTuning.lqr.c).reshape((1,2))
|
|
self.K = np.array(CP.lateralTuning.lqr.k).reshape((1,2))
|
|
self.L = np.array(CP.lateralTuning.lqr.l).reshape((2,1))
|
|
self.dc_gain = CP.lateralTuning.lqr.dcGain
|
|
|
|
self.x_hat = np.array([[0], [0]])
|
|
self.i_unwind_rate = 0.3 * DT_CTRL
|
|
self.i_rate = 1.0 * DT_CTRL
|
|
|
|
self.sat_count_rate = 1.0 * DT_CTRL
|
|
self.sat_limit = CP.steerLimitTimer
|
|
|
|
self.reset()
|
|
|
|
def reset(self):
|
|
self.i_lqr = 0.0
|
|
self.output_steer = 0.0
|
|
self.sat_count = 0.0
|
|
|
|
def _check_saturation(self, control, check_saturation, limit):
|
|
saturated = abs(control) == limit
|
|
|
|
if saturated and check_saturation:
|
|
self.sat_count += self.sat_count_rate
|
|
else:
|
|
self.sat_count -= self.sat_count_rate
|
|
|
|
self.sat_count = clip(self.sat_count, 0.0, 1.0)
|
|
|
|
return self.sat_count > self.sat_limit
|
|
|
|
def update(self, active, CS, CP, path_plan):
|
|
lqr_log = log.ControlsState.LateralLQRState.new_message()
|
|
|
|
steers_max = get_steer_max(CP, CS.vEgo)
|
|
torque_scale = (0.45 + CS.vEgo / 60.0)**2 # Scale actuator model with speed
|
|
|
|
steering_angle = CS.steeringAngle
|
|
|
|
# Subtract offset. Zero angle should correspond to zero torque
|
|
self.angle_steers_des = path_plan.angleSteers - path_plan.angleOffset
|
|
steering_angle -= path_plan.angleOffset
|
|
|
|
# Update Kalman filter
|
|
angle_steers_k = float(self.C.dot(self.x_hat))
|
|
e = steering_angle - angle_steers_k
|
|
self.x_hat = self.A.dot(self.x_hat) + self.B.dot(CS.steeringTorqueEps / torque_scale) + self.L.dot(e)
|
|
|
|
if CS.vEgo < 0.3 or not active:
|
|
lqr_log.active = False
|
|
lqr_output = 0.
|
|
self.reset()
|
|
else:
|
|
lqr_log.active = True
|
|
|
|
# LQR
|
|
u_lqr = float(self.angle_steers_des / self.dc_gain - self.K.dot(self.x_hat))
|
|
lqr_output = torque_scale * u_lqr / self.scale
|
|
|
|
# Integrator
|
|
if CS.steeringPressed:
|
|
self.i_lqr -= self.i_unwind_rate * float(np.sign(self.i_lqr))
|
|
else:
|
|
error = self.angle_steers_des - angle_steers_k
|
|
i = self.i_lqr + self.ki * self.i_rate * error
|
|
control = lqr_output + i
|
|
|
|
if (error >= 0 and (control <= steers_max or i < 0.0)) or \
|
|
(error <= 0 and (control >= -steers_max or i > 0.0)):
|
|
self.i_lqr = i
|
|
|
|
self.output_steer = lqr_output + self.i_lqr
|
|
self.output_steer = clip(self.output_steer, -steers_max, steers_max)
|
|
|
|
check_saturation = (CS.vEgo > 10) and not CS.steeringRateLimited and not CS.steeringPressed
|
|
saturated = self._check_saturation(self.output_steer, check_saturation, steers_max)
|
|
|
|
lqr_log.steerAngle = angle_steers_k + path_plan.angleOffset
|
|
lqr_log.i = self.i_lqr
|
|
lqr_log.output = self.output_steer
|
|
lqr_log.lqrOutput = lqr_output
|
|
lqr_log.saturated = saturated
|
|
return self.output_steer, float(self.angle_steers_des), lqr_log
|
|
|