openpilot0/selfdrive/controls/lib/tests/test_vehicle_model.py

69 lines
2.5 KiB
Python

import pytest
import math
import numpy as np
from opendbc.car.honda.interface import CarInterface
from opendbc.car.honda.values import CAR
from openpilot.selfdrive.car.card import convert_to_capnp
from openpilot.selfdrive.controls.lib.vehicle_model import VehicleModel, dyn_ss_sol, create_dyn_state_matrices
class TestVehicleModel:
def setup_method(self):
CP = CarInterface.get_non_essential_params(CAR.HONDA_CIVIC)
self.VM = VehicleModel(convert_to_capnp(CP))
def test_round_trip_yaw_rate(self):
# TODO: fix VM to work at zero speed
for u in np.linspace(1, 30, num=10):
for roll in np.linspace(math.radians(-20), math.radians(20), num=11):
for sa in np.linspace(math.radians(-20), math.radians(20), num=11):
yr = self.VM.yaw_rate(sa, u, roll)
new_sa = self.VM.get_steer_from_yaw_rate(yr, u, roll)
assert sa == pytest.approx(new_sa)
def test_dyn_ss_sol_against_yaw_rate(self):
"""Verify that the yaw_rate helper function matches the results
from the state space model."""
for roll in np.linspace(math.radians(-20), math.radians(20), num=11):
for u in np.linspace(1, 30, num=10):
for sa in np.linspace(math.radians(-20), math.radians(20), num=11):
# Compute yaw rate based on state space model
_, yr1 = dyn_ss_sol(sa, u, roll, self.VM)
# Compute yaw rate using direct computations
yr2 = self.VM.yaw_rate(sa, u, roll)
assert float(yr1[0]) == pytest.approx(yr2)
def test_syn_ss_sol_simulate(self):
"""Verifies that dyn_ss_sol matches a simulation"""
for roll in np.linspace(math.radians(-20), math.radians(20), num=11):
for u in np.linspace(1, 30, num=10):
A, B = create_dyn_state_matrices(u, self.VM)
# Convert to discrete time system
dt = 0.01
top = np.hstack((A, B))
full = np.vstack((top, np.zeros_like(top))) * dt
Md = sum([np.linalg.matrix_power(full, k) / math.factorial(k) for k in range(25)])
Ad = Md[:A.shape[0], :A.shape[1]]
Bd = Md[:A.shape[0], A.shape[1]:]
for sa in np.linspace(math.radians(-20), math.radians(20), num=11):
inp = np.array([[sa], [roll]])
# Simulate for 1 second
x1 = np.zeros((2, 1))
for _ in range(100):
x1 = Ad @ x1 + Bd @ inp
# Compute steady state solution directly
x2 = dyn_ss_sol(sa, u, roll, self.VM)
np.testing.assert_almost_equal(x1, x2, decimal=3)