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PythonRobotics/PathPlanning/QuinticPolynomialsPlanner/quintic_polynomials_planner.py
Göktuğ Karakaşlı d019e416ba exit on key
2019-12-07 14:30:18 +03:00

237 lines
6.4 KiB
Python

"""
Quintic Polynomials Planner
author: Atsushi Sakai (@Atsushi_twi)
Ref:
- [Local Path planning And Motion Control For Agv In Positioning](http://ieeexplore.ieee.org/document/637936/)
"""
import math
import matplotlib.pyplot as plt
import numpy as np
# parameter
MAX_T = 100.0 # maximum time to the goal [s]
MIN_T = 5.0 # minimum time to the goal[s]
show_animation = True
class QuinticPolynomial:
def __init__(self, xs, vxs, axs, xe, vxe, axe, T):
# calc coefficient of quinic polynomial
self.xs = xs
self.vxs = vxs
self.axs = axs
self.xe = xe
self.vxe = vxe
self.axe = axe
self.a0 = xs
self.a1 = vxs
self.a2 = axs / 2.0
A = np.array([[T**3, T**4, T**5],
[3 * T ** 2, 4 * T ** 3, 5 * T ** 4],
[6 * T, 12 * T ** 2, 20 * T ** 3]])
b = np.array([xe - self.a0 - self.a1 * T - self.a2 * T**2,
vxe - self.a1 - 2 * self.a2 * T,
axe - 2 * self.a2])
x = np.linalg.solve(A, b)
self.a3 = x[0]
self.a4 = x[1]
self.a5 = x[2]
def calc_point(self, t):
xt = self.a0 + self.a1 * t + self.a2 * t**2 + \
self.a3 * t**3 + self.a4 * t**4 + self.a5 * t**5
return xt
def calc_first_derivative(self, t):
xt = self.a1 + 2 * self.a2 * t + \
3 * self.a3 * t**2 + 4 * self.a4 * t**3 + 5 * self.a5 * t**4
return xt
def calc_second_derivative(self, t):
xt = 2 * self.a2 + 6 * self.a3 * t + 12 * self.a4 * t**2 + 20 * self.a5 * t**3
return xt
def calc_third_derivative(self, t):
xt = 6 * self.a3 + 24 * self.a4 * t + 60 * self.a5 * t**2
return xt
def quintic_polynomials_planner(sx, sy, syaw, sv, sa, gx, gy, gyaw, gv, ga, max_accel, max_jerk, dt):
"""
quintic polynomial planner
input
sx: start x position [m]
sy: start y position [m]
syaw: start yaw angle [rad]
sa: start accel [m/ss]
gx: goal x position [m]
gy: goal y position [m]
gyaw: goal yaw angle [rad]
ga: goal accel [m/ss]
max_accel: maximum accel [m/ss]
max_jerk: maximum jerk [m/sss]
dt: time tick [s]
return
time: time result
rx: x position result list
ry: y position result list
ryaw: yaw angle result list
rv: velocity result list
ra: accel result list
"""
vxs = sv * math.cos(syaw)
vys = sv * math.sin(syaw)
vxg = gv * math.cos(gyaw)
vyg = gv * math.sin(gyaw)
axs = sa * math.cos(syaw)
ays = sa * math.sin(syaw)
axg = ga * math.cos(gyaw)
ayg = ga * math.sin(gyaw)
time, rx, ry, ryaw, rv, ra, rj = [], [], [], [], [], [], []
for T in np.arange(MIN_T, MAX_T, MIN_T):
xqp = QuinticPolynomial(sx, vxs, axs, gx, vxg, axg, T)
yqp = QuinticPolynomial(sy, vys, ays, gy, vyg, ayg, T)
time, rx, ry, ryaw, rv, ra, rj = [], [], [], [], [], [], []
for t in np.arange(0.0, T + dt, dt):
time.append(t)
rx.append(xqp.calc_point(t))
ry.append(yqp.calc_point(t))
vx = xqp.calc_first_derivative(t)
vy = yqp.calc_first_derivative(t)
v = np.hypot(vx, vy)
yaw = math.atan2(vy, vx)
rv.append(v)
ryaw.append(yaw)
ax = xqp.calc_second_derivative(t)
ay = yqp.calc_second_derivative(t)
a = np.hypot(ax, ay)
if len(rv) >= 2 and rv[-1] - rv[-2] < 0.0:
a *= -1
ra.append(a)
jx = xqp.calc_third_derivative(t)
jy = yqp.calc_third_derivative(t)
j = np.hypot(jx, jy)
if len(ra) >= 2 and ra[-1] - ra[-2] < 0.0:
j *= -1
rj.append(j)
if max([abs(i) for i in ra]) <= max_accel and max([abs(i) for i in rj]) <= max_jerk:
print("find path!!")
break
if show_animation: # pragma: no cover
for i, _ in enumerate(time):
plt.cla()
plt.gcf().canvas.mpl_connect('key_release_event',
lambda event: [exit(0) if event.key == 'escape' else None])
plt.grid(True)
plt.axis("equal")
plot_arrow(sx, sy, syaw)
plot_arrow(gx, gy, gyaw)
plot_arrow(rx[i], ry[i], ryaw[i])
plt.title("Time[s]:" + str(time[i])[0:4] +
" v[m/s]:" + str(rv[i])[0:4] +
" a[m/ss]:" + str(ra[i])[0:4] +
" jerk[m/sss]:" + str(rj[i])[0:4],
)
plt.pause(0.001)
return time, rx, ry, ryaw, rv, ra, rj
def plot_arrow(x, y, yaw, length=1.0, width=0.5, fc="r", ec="k"): # pragma: no cover
"""
Plot arrow
"""
if not isinstance(x, float):
for (ix, iy, iyaw) in zip(x, y, yaw):
plot_arrow(ix, iy, iyaw)
else:
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)
def main():
print(__file__ + " start!!")
sx = 10.0 # start x position [m]
sy = 10.0 # start y position [m]
syaw = np.deg2rad(10.0) # start yaw angle [rad]
sv = 1.0 # start speed [m/s]
sa = 0.1 # start accel [m/ss]
gx = 30.0 # goal x position [m]
gy = -10.0 # goal y position [m]
gyaw = np.deg2rad(20.0) # goal yaw angle [rad]
gv = 1.0 # goal speed [m/s]
ga = 0.1 # goal accel [m/ss]
max_accel = 1.0 # max accel [m/ss]
max_jerk = 0.5 # max jerk [m/sss]
dt = 0.1 # time tick [s]
time, x, y, yaw, v, a, j = quintic_polynomials_planner(
sx, sy, syaw, sv, sa, gx, gy, gyaw, gv, ga, max_accel, max_jerk, dt)
if show_animation: # pragma: no cover
plt.plot(x, y, "-r")
plt.subplots()
plt.plot(time, [np.rad2deg(i) for i in yaw], "-r")
plt.xlabel("Time[s]")
plt.ylabel("Yaw[deg]")
plt.grid(True)
plt.subplots()
plt.plot(time, v, "-r")
plt.xlabel("Time[s]")
plt.ylabel("Speed[m/s]")
plt.grid(True)
plt.subplots()
plt.plot(time, a, "-r")
plt.xlabel("Time[s]")
plt.ylabel("accel[m/ss]")
plt.grid(True)
plt.subplots()
plt.plot(time, j, "-r")
plt.xlabel("Time[s]")
plt.ylabel("jerk[m/sss]")
plt.grid(True)
plt.show()
if __name__ == '__main__':
main()