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.
91 lines
4.7 KiB
91 lines
4.7 KiB
import math
|
|
|
|
from cereal import log
|
|
from openpilot.common.numpy_fast import interp
|
|
from openpilot.selfdrive.controls.lib.latcontrol import LatControl
|
|
from openpilot.selfdrive.controls.lib.pid import PIDController
|
|
from openpilot.selfdrive.controls.lib.vehicle_model import ACCELERATION_DUE_TO_GRAVITY
|
|
|
|
# At higher speeds (25+mph) we can assume:
|
|
# Lateral acceleration achieved by a specific car correlates to
|
|
# torque applied to the steering rack. It does not correlate to
|
|
# wheel slip, or to speed.
|
|
|
|
# This controller applies torque to achieve desired lateral
|
|
# accelerations. To compensate for the low speed effects we
|
|
# use a LOW_SPEED_FACTOR in the error. Additionally, there is
|
|
# friction in the steering wheel that needs to be overcome to
|
|
# move it at all, this is compensated for too.
|
|
|
|
LOW_SPEED_X = [0, 10, 20, 30]
|
|
LOW_SPEED_Y = [15, 13, 10, 5]
|
|
|
|
|
|
class LatControlTorque(LatControl):
|
|
def __init__(self, CP, CI):
|
|
super().__init__(CP, CI)
|
|
self.torque_params = CP.lateralTuning.torque
|
|
self.pid = PIDController(self.torque_params.kp, self.torque_params.ki,
|
|
k_f=self.torque_params.kf, pos_limit=self.steer_max, neg_limit=-self.steer_max)
|
|
self.torque_from_lateral_accel = CI.torque_from_lateral_accel()
|
|
self.use_steering_angle = self.torque_params.useSteeringAngle
|
|
self.steering_angle_deadzone_deg = self.torque_params.steeringAngleDeadzoneDeg
|
|
|
|
def update_live_torque_params(self, latAccelFactor, latAccelOffset, friction):
|
|
self.torque_params.latAccelFactor = latAccelFactor
|
|
self.torque_params.latAccelOffset = latAccelOffset
|
|
self.torque_params.friction = friction
|
|
|
|
def update(self, active, CS, VM, params, steer_limited, desired_curvature, desired_curvature_rate, llk):
|
|
pid_log = log.ControlsState.LateralTorqueState.new_message()
|
|
|
|
if not active:
|
|
output_torque = 0.0
|
|
pid_log.active = False
|
|
else:
|
|
if self.use_steering_angle:
|
|
actual_curvature = -VM.calc_curvature(math.radians(CS.steeringAngleDeg - params.angleOffsetDeg), CS.vEgo, params.roll)
|
|
curvature_deadzone = abs(VM.calc_curvature(math.radians(self.steering_angle_deadzone_deg), CS.vEgo, 0.0))
|
|
else:
|
|
actual_curvature_vm = -VM.calc_curvature(math.radians(CS.steeringAngleDeg - params.angleOffsetDeg), CS.vEgo, params.roll)
|
|
actual_curvature_llk = llk.angularVelocityCalibrated.value[2] / CS.vEgo
|
|
actual_curvature = interp(CS.vEgo, [2.0, 5.0], [actual_curvature_vm, actual_curvature_llk])
|
|
curvature_deadzone = 0.0
|
|
desired_lateral_accel = desired_curvature * CS.vEgo ** 2
|
|
|
|
# desired rate is the desired rate of change in the setpoint, not the absolute desired curvature
|
|
# desired_lateral_jerk = desired_curvature_rate * CS.vEgo ** 2
|
|
actual_lateral_accel = actual_curvature * CS.vEgo ** 2
|
|
lateral_accel_deadzone = curvature_deadzone * CS.vEgo ** 2
|
|
|
|
low_speed_factor = interp(CS.vEgo, LOW_SPEED_X, LOW_SPEED_Y)**2
|
|
setpoint = desired_lateral_accel + low_speed_factor * desired_curvature
|
|
measurement = actual_lateral_accel + low_speed_factor * actual_curvature
|
|
gravity_adjusted_lateral_accel = desired_lateral_accel - params.roll * ACCELERATION_DUE_TO_GRAVITY
|
|
torque_from_setpoint = self.torque_from_lateral_accel(setpoint, self.torque_params, setpoint,
|
|
lateral_accel_deadzone, friction_compensation=False)
|
|
torque_from_measurement = self.torque_from_lateral_accel(measurement, self.torque_params, measurement,
|
|
lateral_accel_deadzone, friction_compensation=False)
|
|
pid_log.error = torque_from_setpoint - torque_from_measurement
|
|
ff = self.torque_from_lateral_accel(gravity_adjusted_lateral_accel, self.torque_params,
|
|
desired_lateral_accel - actual_lateral_accel,
|
|
lateral_accel_deadzone, friction_compensation=True)
|
|
|
|
freeze_integrator = steer_limited or CS.steeringPressed or CS.vEgo < 5
|
|
output_torque = self.pid.update(pid_log.error,
|
|
feedforward=ff,
|
|
speed=CS.vEgo,
|
|
freeze_integrator=freeze_integrator)
|
|
|
|
pid_log.active = True
|
|
pid_log.p = self.pid.p
|
|
pid_log.i = self.pid.i
|
|
pid_log.d = self.pid.d
|
|
pid_log.f = self.pid.f
|
|
pid_log.output = -output_torque
|
|
pid_log.actualLateralAccel = actual_lateral_accel
|
|
pid_log.desiredLateralAccel = desired_lateral_accel
|
|
pid_log.saturated = self._check_saturation(self.steer_max - abs(output_torque) < 1e-3, CS, steer_limited)
|
|
|
|
# TODO left is positive in this convention
|
|
return -output_torque, 0.0, pid_log
|
|
|