move these too

car/__init__.py

@@ -0,0 +1,278 @@
+# functions common among cars
+from collections import namedtuple
+from dataclasses import dataclass
+from enum import IntFlag, ReprEnum, EnumType
+from dataclasses import replace
+
+import capnp
+
+from cereal import car
+from openpilot.common.numpy_fast import clip, interp
+from openpilot.common.utils import Freezable
+from openpilot.selfdrive.car.docs_definitions import CarDocs
+
+
+# kg of standard extra cargo to count for drive, gas, etc...
+STD_CARGO_KG = 136.
+
+ButtonType = car.CarState.ButtonEvent.Type
+EventName = car.CarEvent.EventName
+AngleRateLimit = namedtuple('AngleRateLimit', ['speed_bp', 'angle_v'])
+
+
+def apply_hysteresis(val: float, val_steady: float, hyst_gap: float) -> float:
+  if val > val_steady + hyst_gap:
+    val_steady = val - hyst_gap
+  elif val < val_steady - hyst_gap:
+    val_steady = val + hyst_gap
+  return val_steady
+
+
+def create_button_events(cur_btn: int, prev_btn: int, buttons_dict: dict[int, capnp.lib.capnp._EnumModule],
+                         unpressed_btn: int = 0) -> list[capnp.lib.capnp._DynamicStructBuilder]:
+  events: list[capnp.lib.capnp._DynamicStructBuilder] = []
+
+  if cur_btn == prev_btn:
+    return events
+
+  # Add events for button presses, multiple when a button switches without going to unpressed
+  for pressed, btn in ((False, prev_btn), (True, cur_btn)):
+    if btn != unpressed_btn:
+      events.append(car.CarState.ButtonEvent(pressed=pressed,
+                                             type=buttons_dict.get(btn, ButtonType.unknown)))
+  return events
+
+
+def gen_empty_fingerprint():
+  return {i: {} for i in range(8)}
+
+
+# these params were derived for the Civic and used to calculate params for other cars
+class VehicleDynamicsParams:
+  MASS = 1326. + STD_CARGO_KG
+  WHEELBASE = 2.70
+  CENTER_TO_FRONT = WHEELBASE * 0.4
+  CENTER_TO_REAR = WHEELBASE - CENTER_TO_FRONT
+  ROTATIONAL_INERTIA = 2500
+  TIRE_STIFFNESS_FRONT = 192150
+  TIRE_STIFFNESS_REAR = 202500
+
+
+# TODO: get actual value, for now starting with reasonable value for
+# civic and scaling by mass and wheelbase
+def scale_rot_inertia(mass, wheelbase):
+  return VehicleDynamicsParams.ROTATIONAL_INERTIA * mass * wheelbase ** 2 / (VehicleDynamicsParams.MASS * VehicleDynamicsParams.WHEELBASE ** 2)
+
+
+# TODO: start from empirically derived lateral slip stiffness for the civic and scale by
+# mass and CG position, so all cars will have approximately similar dyn behaviors
+def scale_tire_stiffness(mass, wheelbase, center_to_front, tire_stiffness_factor):
+  center_to_rear = wheelbase - center_to_front
+  tire_stiffness_front = (VehicleDynamicsParams.TIRE_STIFFNESS_FRONT * tire_stiffness_factor) * mass / VehicleDynamicsParams.MASS * \
+                         (center_to_rear / wheelbase) / (VehicleDynamicsParams.CENTER_TO_REAR / VehicleDynamicsParams.WHEELBASE)
+
+  tire_stiffness_rear = (VehicleDynamicsParams.TIRE_STIFFNESS_REAR * tire_stiffness_factor) * mass / VehicleDynamicsParams.MASS * \
+                        (center_to_front / wheelbase) / (VehicleDynamicsParams.CENTER_TO_FRONT / VehicleDynamicsParams.WHEELBASE)
+
+  return tire_stiffness_front, tire_stiffness_rear
+
+
+DbcDict = dict[str, str]
+
+
+def dbc_dict(pt_dbc, radar_dbc, chassis_dbc=None, body_dbc=None) -> DbcDict:
+  return {'pt': pt_dbc, 'radar': radar_dbc, 'chassis': chassis_dbc, 'body': body_dbc}
+
+
+def apply_driver_steer_torque_limits(apply_torque, apply_torque_last, driver_torque, LIMITS):
+
+  # limits due to driver torque
+  driver_max_torque = LIMITS.STEER_MAX + (LIMITS.STEER_DRIVER_ALLOWANCE + driver_torque * LIMITS.STEER_DRIVER_FACTOR) * LIMITS.STEER_DRIVER_MULTIPLIER
+  driver_min_torque = -LIMITS.STEER_MAX + (-LIMITS.STEER_DRIVER_ALLOWANCE + driver_torque * LIMITS.STEER_DRIVER_FACTOR) * LIMITS.STEER_DRIVER_MULTIPLIER
+  max_steer_allowed = max(min(LIMITS.STEER_MAX, driver_max_torque), 0)
+  min_steer_allowed = min(max(-LIMITS.STEER_MAX, driver_min_torque), 0)
+  apply_torque = clip(apply_torque, min_steer_allowed, max_steer_allowed)
+
+  # slow rate if steer torque increases in magnitude
+  if apply_torque_last > 0:
+    apply_torque = clip(apply_torque, max(apply_torque_last - LIMITS.STEER_DELTA_DOWN, -LIMITS.STEER_DELTA_UP),
+                        apply_torque_last + LIMITS.STEER_DELTA_UP)
+  else:
+    apply_torque = clip(apply_torque, apply_torque_last - LIMITS.STEER_DELTA_UP,
+                        min(apply_torque_last + LIMITS.STEER_DELTA_DOWN, LIMITS.STEER_DELTA_UP))
+
+  return int(round(float(apply_torque)))
+
+
+def apply_dist_to_meas_limits(val, val_last, val_meas,
+                              STEER_DELTA_UP, STEER_DELTA_DOWN,
+                              STEER_ERROR_MAX, STEER_MAX):
+  # limits due to comparison of commanded val VS measured val (torque/angle/curvature)
+  max_lim = min(max(val_meas + STEER_ERROR_MAX, STEER_ERROR_MAX), STEER_MAX)
+  min_lim = max(min(val_meas - STEER_ERROR_MAX, -STEER_ERROR_MAX), -STEER_MAX)
+
+  val = clip(val, min_lim, max_lim)
+
+  # slow rate if val increases in magnitude
+  if val_last > 0:
+    val = clip(val,
+               max(val_last - STEER_DELTA_DOWN, -STEER_DELTA_UP),
+               val_last + STEER_DELTA_UP)
+  else:
+    val = clip(val,
+               val_last - STEER_DELTA_UP,
+               min(val_last + STEER_DELTA_DOWN, STEER_DELTA_UP))
+
+  return float(val)
+
+
+def apply_meas_steer_torque_limits(apply_torque, apply_torque_last, motor_torque, LIMITS):
+  return int(round(apply_dist_to_meas_limits(apply_torque, apply_torque_last, motor_torque,
+                                             LIMITS.STEER_DELTA_UP, LIMITS.STEER_DELTA_DOWN,
+                                             LIMITS.STEER_ERROR_MAX, LIMITS.STEER_MAX)))
+
+
+def apply_std_steer_angle_limits(apply_angle, apply_angle_last, v_ego, LIMITS):
+  # pick angle rate limits based on wind up/down
+  steer_up = apply_angle_last * apply_angle >= 0. and abs(apply_angle) > abs(apply_angle_last)
+  rate_limits = LIMITS.ANGLE_RATE_LIMIT_UP if steer_up else LIMITS.ANGLE_RATE_LIMIT_DOWN
+
+  angle_rate_lim = interp(v_ego, rate_limits.speed_bp, rate_limits.angle_v)
+  return clip(apply_angle, apply_angle_last - angle_rate_lim, apply_angle_last + angle_rate_lim)
+
+
+def common_fault_avoidance(fault_condition: bool, request: bool, above_limit_frames: int,
+                           max_above_limit_frames: int, max_mismatching_frames: int = 1):
+  """
+  Several cars have the ability to work around their EPS limits by cutting the
+  request bit of their LKAS message after a certain number of frames above the limit.
+  """
+
+  # Count up to max_above_limit_frames, at which point we need to cut the request for above_limit_frames to avoid a fault
+  if request and fault_condition:
+    above_limit_frames += 1
+  else:
+    above_limit_frames = 0
+
+  # Once we cut the request bit, count additionally to max_mismatching_frames before setting the request bit high again.
+  # Some brands do not respect our workaround without multiple messages on the bus, for example
+  if above_limit_frames > max_above_limit_frames:
+    request = False
+
+  if above_limit_frames >= max_above_limit_frames + max_mismatching_frames:
+    above_limit_frames = 0
+
+  return above_limit_frames, request
+
+
+def make_can_msg(addr, dat, bus):
+  return [addr, 0, dat, bus]
+
+
+def get_safety_config(safety_model, safety_param = None):
+  ret = car.CarParams.SafetyConfig.new_message()
+  ret.safetyModel = safety_model
+  if safety_param is not None:
+    ret.safetyParam = safety_param
+  return ret
+
+
+class CanBusBase:
+  offset: int
+
+  def __init__(self, CP, fingerprint: dict[int, dict[int, int]] | None) -> None:
+    if CP is None:
+      assert fingerprint is not None
+      num = max([k for k, v in fingerprint.items() if len(v)], default=0) // 4 + 1
+    else:
+      num = len(CP.safetyConfigs)
+    self.offset = 4 * (num - 1)
+
+
+class CanSignalRateCalculator:
+  """
+  Calculates the instantaneous rate of a CAN signal by using the counter
+  variable and the known frequency of the CAN message that contains it.
+  """
+  def __init__(self, frequency):
+    self.frequency = frequency
+    self.previous_counter = 0
+    self.previous_value = 0
+    self.rate = 0
+
+  def update(self, current_value, current_counter):
+    if current_counter != self.previous_counter:
+      self.rate = (current_value - self.previous_value) * self.frequency
+
+    self.previous_counter = current_counter
+    self.previous_value = current_value
+
+    return self.rate
+
+
+@dataclass(frozen=True, kw_only=True)
+class CarSpecs:
+  mass: float  # kg, curb weight
+  wheelbase: float  # meters
+  steerRatio: float
+  centerToFrontRatio: float = 0.5
+  minSteerSpeed: float = 0.0  # m/s
+  minEnableSpeed: float = -1.0  # m/s
+  tireStiffnessFactor: float = 1.0
+
+  def override(self, **kwargs):
+    return replace(self, **kwargs)
+
+
+@dataclass(order=True)
+class PlatformConfig(Freezable):
+  car_docs: list[CarDocs]
+  specs: CarSpecs
+
+  dbc_dict: DbcDict
+
+  flags: int = 0
+
+  platform_str: str | None = None
+
+  def __hash__(self) -> int:
+    return hash(self.platform_str)
+
+  def override(self, **kwargs):
+    return replace(self, **kwargs)
+
+  def init(self):
+    pass
+
+  def __post_init__(self):
+    self.init()
+
+
+class PlatformsType(EnumType):
+  def __new__(metacls, cls, bases, classdict, *, boundary=None, _simple=False, **kwds):
+    for key in classdict._member_names.keys():
+      cfg: PlatformConfig = classdict[key]
+      cfg.platform_str = key
+      cfg.freeze()
+    return super().__new__(metacls, cls, bases, classdict, boundary=boundary, _simple=_simple, **kwds)
+
+
+class Platforms(str, ReprEnum, metaclass=PlatformsType):
+  config: PlatformConfig
+
+  def __new__(cls, platform_config: PlatformConfig):
+    member = str.__new__(cls, platform_config.platform_str)
+    member.config = platform_config
+    member._value_ = platform_config.platform_str
+    return member
+
+  def __repr__(self):
+    return f"<{self.__class__.__name__}.{self.name}>"
+
+  @classmethod
+  def create_dbc_map(cls) -> dict[str, DbcDict]:
+    return {p: p.config.dbc_dict for p in cls}
+
+  @classmethod
+  def with_flags(cls, flags: IntFlag) -> set['Platforms']:
+    return {p for p in cls if p.config.flags & flags}