Files
PythonRobotics/PathPlanning/ModelPredictiveTrajectoryGenerator/trajectory_generator.py
Videh Patel cc3fd0c55e Using util.angle_mod in all codes. #684 (#946)
* switched to using utils.angle_mod()

* switched to using utils.angle_mod()

* renamed mod2pi to pi_2_pi

* Removed linting errors

* switched to using utils.angle_mod()

* switched to using utils.angle_mod()

* renamed mod2pi to pi_2_pi

* Removed linting errors

* annotation changes and round precision

* Reverted to mod2pi

---------

Co-authored-by: Videh Patel <videh.patel@fluxauto.xyz>
2024-01-02 22:39:48 +09:00

163 lines
4.3 KiB
Python

"""
Model trajectory generator
author: Atsushi Sakai(@Atsushi_twi)
"""
import math
import matplotlib.pyplot as plt
import numpy as np
import sys
import pathlib
path_planning_dir = pathlib.Path(__file__).parent.parent
sys.path.append(str(path_planning_dir))
import ModelPredictiveTrajectoryGenerator.motion_model as motion_model
# optimization parameter
max_iter = 100
h: np.ndarray = np.array([0.5, 0.02, 0.02]).T # parameter sampling distance
cost_th = 0.1
show_animation = True
def plot_arrow(x, y, yaw, length=1.0, width=0.5, fc="r", ec="k"): # pragma: no cover
"""
Plot arrow
"""
plt.arrow(x, y, length * math.cos(yaw), length * math.sin(yaw),
fc=fc, ec=ec, head_width=width, head_length=width)
plt.plot(x, y)
plt.plot(0, 0)
def calc_diff(target, x, y, yaw):
d = np.array([target.x - x[-1],
target.y - y[-1],
motion_model.pi_2_pi(target.yaw - yaw[-1])])
return d
def calc_j(target, p, h, k0):
xp, yp, yawp = motion_model.generate_last_state(
p[0, 0] + h[0], p[1, 0], p[2, 0], k0)
dp = calc_diff(target, [xp], [yp], [yawp])
xn, yn, yawn = motion_model.generate_last_state(
p[0, 0] - h[0], p[1, 0], p[2, 0], k0)
dn = calc_diff(target, [xn], [yn], [yawn])
d1 = np.array((dp - dn) / (2.0 * h[0])).reshape(3, 1)
xp, yp, yawp = motion_model.generate_last_state(
p[0, 0], p[1, 0] + h[1], p[2, 0], k0)
dp = calc_diff(target, [xp], [yp], [yawp])
xn, yn, yawn = motion_model.generate_last_state(
p[0, 0], p[1, 0] - h[1], p[2, 0], k0)
dn = calc_diff(target, [xn], [yn], [yawn])
d2 = np.array((dp - dn) / (2.0 * h[1])).reshape(3, 1)
xp, yp, yawp = motion_model.generate_last_state(
p[0, 0], p[1, 0], p[2, 0] + h[2], k0)
dp = calc_diff(target, [xp], [yp], [yawp])
xn, yn, yawn = motion_model.generate_last_state(
p[0, 0], p[1, 0], p[2, 0] - h[2], k0)
dn = calc_diff(target, [xn], [yn], [yawn])
d3 = np.array((dp - dn) / (2.0 * h[2])).reshape(3, 1)
J = np.hstack((d1, d2, d3))
return J
def selection_learning_param(dp, p, k0, target):
mincost = float("inf")
mina = 1.0
maxa = 2.0
da = 0.5
for a in np.arange(mina, maxa, da):
tp = p + a * dp
xc, yc, yawc = motion_model.generate_last_state(
tp[0], tp[1], tp[2], k0)
dc = calc_diff(target, [xc], [yc], [yawc])
cost = np.linalg.norm(dc)
if cost <= mincost and a != 0.0:
mina = a
mincost = cost
# print(mincost, mina)
# input()
return mina
def show_trajectory(target, xc, yc): # pragma: no cover
plt.clf()
plot_arrow(target.x, target.y, target.yaw)
plt.plot(xc, yc, "-r")
plt.axis("equal")
plt.grid(True)
plt.pause(0.1)
def optimize_trajectory(target, k0, p):
for i in range(max_iter):
xc, yc, yawc = motion_model.generate_trajectory(p[0, 0], p[1, 0], p[2, 0], k0)
dc = np.array(calc_diff(target, xc, yc, yawc)).reshape(3, 1)
cost = np.linalg.norm(dc)
if cost <= cost_th:
print("path is ok cost is:" + str(cost))
break
J = calc_j(target, p, h, k0)
try:
dp = - np.linalg.inv(J) @ dc
except np.linalg.linalg.LinAlgError:
print("cannot calc path LinAlgError")
xc, yc, yawc, p = None, None, None, None
break
alpha = selection_learning_param(dp, p, k0, target)
p += alpha * np.array(dp)
# print(p.T)
if show_animation: # pragma: no cover
show_trajectory(target, xc, yc)
else:
xc, yc, yawc, p = None, None, None, None
print("cannot calc path")
return xc, yc, yawc, p
def optimize_trajectory_demo(): # pragma: no cover
# target = motion_model.State(x=5.0, y=2.0, yaw=np.deg2rad(00.0))
target = motion_model.State(x=5.0, y=2.0, yaw=np.deg2rad(90.0))
k0 = 0.0
init_p = np.array([6.0, 0.0, 0.0]).reshape(3, 1)
x, y, yaw, p = optimize_trajectory(target, k0, init_p)
if show_animation:
show_trajectory(target, x, y)
plot_arrow(target.x, target.y, target.yaw)
plt.axis("equal")
plt.grid(True)
plt.show()
def main(): # pragma: no cover
print(__file__ + " start!!")
optimize_trajectory_demo()
if __name__ == '__main__':
main()