add global positoon projection

This commit is contained in:
Atsushi Sakai
2018-01-11 15:36:51 -08:00
parent 0d46bbeac8
commit db4f70d1d9
2 changed files with 271 additions and 6 deletions

View File

@@ -0,0 +1,239 @@
"""
cubic spline planner
Author: Atsushi Sakai
"""
import math
import numpy as np
import bisect
class Spline:
u"""
Cubic Spline class
"""
def __init__(self, x, y):
self.b, self.c, self.d, self.w = [], [], [], []
self.x = x
self.y = y
self.nx = len(x) # dimension of x
h = np.diff(x)
# calc coefficient c
self.a = [iy for iy in y]
# calc coefficient c
A = self.__calc_A(h)
B = self.__calc_B(h)
self.c = np.linalg.solve(A, B)
# print(self.c1)
# calc spline coefficient b and d
for i in range(self.nx - 1):
self.d.append((self.c[i + 1] - self.c[i]) / (3.0 * h[i]))
tb = (self.a[i + 1] - self.a[i]) / h[i] - h[i] * \
(self.c[i + 1] + 2.0 * self.c[i]) / 3.0
self.b.append(tb)
def calc(self, t):
u"""
Calc position
if t is outside of the input x, return None
"""
if t < self.x[0]:
return None
elif t > self.x[-1]:
return None
i = self.__search_index(t)
dx = t - self.x[i]
result = self.a[i] + self.b[i] * dx + \
self.c[i] * dx ** 2.0 + self.d[i] * dx ** 3.0
return result
def calcd(self, t):
u"""
Calc first derivative
if t is outside of the input x, return None
"""
if t < self.x[0]:
return None
elif t > self.x[-1]:
return None
i = self.__search_index(t)
dx = t - self.x[i]
result = self.b[i] + 2.0 * self.c[i] * dx + 3.0 * self.d[i] * dx ** 2.0
return result
def calcdd(self, t):
u"""
Calc second derivative
"""
if t < self.x[0]:
return None
elif t > self.x[-1]:
return None
i = self.__search_index(t)
dx = t - self.x[i]
result = 2.0 * self.c[i] + 6.0 * self.d[i] * dx
return result
def __search_index(self, x):
u"""
search data segment index
"""
return bisect.bisect(self.x, x) - 1
def __calc_A(self, h):
u"""
calc matrix A for spline coefficient c
"""
A = np.zeros((self.nx, self.nx))
A[0, 0] = 1.0
for i in range(self.nx - 1):
if i != (self.nx - 2):
A[i + 1, i + 1] = 2.0 * (h[i] + h[i + 1])
A[i + 1, i] = h[i]
A[i, i + 1] = h[i]
A[0, 1] = 0.0
A[self.nx - 1, self.nx - 2] = 0.0
A[self.nx - 1, self.nx - 1] = 1.0
# print(A)
return A
def __calc_B(self, h):
u"""
calc matrix B for spline coefficient c
"""
B = np.zeros(self.nx)
for i in range(self.nx - 2):
B[i + 1] = 3.0 * (self.a[i + 2] - self.a[i + 1]) / \
h[i + 1] - 3.0 * (self.a[i + 1] - self.a[i]) / h[i]
# print(B)
return B
class Spline2D:
u"""
2D Cubic Spline class
"""
def __init__(self, x, y):
self.s = self.__calc_s(x, y)
self.sx = Spline(self.s, x)
self.sy = Spline(self.s, y)
def __calc_s(self, x, y):
dx = np.diff(x)
dy = np.diff(y)
self.ds = [math.sqrt(idx ** 2 + idy ** 2)
for (idx, idy) in zip(dx, dy)]
s = [0]
s.extend(np.cumsum(self.ds))
return s
def calc_position(self, s):
u"""
calc position
"""
x = self.sx.calc(s)
y = self.sy.calc(s)
return x, y
def calc_curvature(self, s):
u"""
calc curvature
"""
dx = self.sx.calcd(s)
ddx = self.sx.calcdd(s)
dy = self.sy.calcd(s)
ddy = self.sy.calcdd(s)
k = (ddy * dx - ddx * dy) / (dx ** 2 + dy ** 2)
return k
def calc_yaw(self, s):
u"""
calc yaw
"""
dx = self.sx.calcd(s)
dy = self.sy.calcd(s)
yaw = math.atan2(dy, dx)
return yaw
def calc_spline_course(x, y, ds=0.1):
sp = Spline2D(x, y)
s = list(np.arange(0, sp.s[-1], ds))
rx, ry, ryaw, rk = [], [], [], []
for i_s in s:
ix, iy = sp.calc_position(i_s)
rx.append(ix)
ry.append(iy)
ryaw.append(sp.calc_yaw(i_s))
rk.append(sp.calc_curvature(i_s))
return rx, ry, ryaw, rk, s
def main():
print("Spline 2D test")
import matplotlib.pyplot as plt
x = [-2.5, 0.0, 2.5, 5.0, 7.5, 3.0, -1.0]
y = [0.7, -6, 5, 6.5, 0.0, 5.0, -2.0]
sp = Spline2D(x, y)
s = np.arange(0, sp.s[-1], 0.1)
rx, ry, ryaw, rk = [], [], [], []
for i_s in s:
ix, iy = sp.calc_position(i_s)
rx.append(ix)
ry.append(iy)
ryaw.append(sp.calc_yaw(i_s))
rk.append(sp.calc_curvature(i_s))
flg, ax = plt.subplots(1)
plt.plot(x, y, "xb", label="input")
plt.plot(rx, ry, "-r", label="spline")
plt.grid(True)
plt.axis("equal")
plt.xlabel("x[m]")
plt.ylabel("y[m]")
plt.legend()
flg, ax = plt.subplots(1)
plt.plot(s, [math.degrees(iyaw) for iyaw in ryaw], "-r", label="yaw")
plt.grid(True)
plt.legend()
plt.xlabel("line length[m]")
plt.ylabel("yaw angle[deg]")
flg, ax = plt.subplots(1)
plt.plot(s, rk, "-r", label="curvature")
plt.grid(True)
plt.legend()
plt.xlabel("line length[m]")
plt.ylabel("curvature [1/m]")
plt.show()
if __name__ == '__main__':
main()

View File

@@ -9,6 +9,7 @@ import numpy as np
import matplotlib.pyplot as plt
import copy
import math
import cubic_spline_planner
class quinic_polynomial:
@@ -160,12 +161,21 @@ def calc_frenet_paths(c_speed, c_d):
return frenet_paths
def calc_global_paths(fplist):
def calc_global_paths(fplist, csp):
for fp in fplist:
fp.x = fp.s
fp.y = fp.d
# calc global positions
for i in range(len(fp.s)):
ix, iy = csp.calc_position(fp.s[i])
iyaw = csp.calc_yaw(fp.s[i])
di = fp.d[i]
fx = ix + di * math.cos(iyaw + math.pi / 2.0)
fy = iy + di * math.sin(iyaw + math.pi / 2.0)
fp.x.append(fx)
fp.y.append(fy)
# calc yaw and ds
for i in range(len(fp.x) - 1):
dx = fp.x[i + 1] - fp.x[i]
dy = fp.y[i + 1] - fp.y[i]
@@ -198,10 +208,10 @@ def check_paths(fplist):
return [fplist[i] for i in okind]
def frenet_optimal_planning(c_speed, c_d):
def frenet_optimal_planning(csp, c_speed, c_d):
fplist = calc_frenet_paths(c_speed, c_d)
fplist = calc_global_paths(fplist)
fplist = calc_global_paths(fplist, csp)
fplist = check_paths(fplist)
for fp in fplist:
@@ -211,10 +221,26 @@ def frenet_optimal_planning(c_speed, c_d):
def main():
print(__file__ + " start!!")
x = [0.0, 10.0, 20.5, 35.0, 70.5]
y = [0.0, -6.0, 5.0, 6.5, 0.0]
csp = cubic_spline_planner.Spline2D(x, y)
s = np.arange(0, csp.s[-1], 0.1)
rx, ry, ryaw, rk = [], [], [], []
for i_s in s:
ix, iy = csp.calc_position(i_s)
rx.append(ix)
ry.append(iy)
ryaw.append(csp.calc_yaw(i_s))
rk.append(csp.calc_curvature(i_s))
c_speed = 10.0 / 3.6 # m/s
c_d = 1.0 # [m]
frenet_optimal_planning(c_speed, c_d)
plt.plot(rx, ry)
frenet_optimal_planning(csp, c_speed, c_d)
plt.axis("equal")
plt.grid(True)