clean up informed_rrt_star.py (#785)

* clean up informed_rrt_star.py

* clean up informed_rrt_star.py
This commit is contained in:
Atsushi Sakai
2023-01-26 22:46:00 +09:00
committed by GitHub
parent 489ee5c0e3
commit 732ed3ea6b

View File

@@ -11,6 +11,7 @@ https://arxiv.org/pdf/1404.2334.pdf
"""
import sys
import pathlib
sys.path.append(str(pathlib.Path(__file__).parent.parent.parent))
import copy
@@ -27,18 +28,17 @@ show_animation = True
class InformedRRTStar:
def __init__(self, start, goal,
obstacleList, randArea,
expandDis=0.5, goalSampleRate=10, maxIter=200):
def __init__(self, start, goal, obstacle_list, rand_area, expand_dis=0.5,
goal_sample_rate=10, max_iter=200):
self.start = Node(start[0], start[1])
self.goal = Node(goal[0], goal[1])
self.min_rand = randArea[0]
self.max_rand = randArea[1]
self.expand_dis = expandDis
self.goal_sample_rate = goalSampleRate
self.max_iter = maxIter
self.obstacle_list = obstacleList
self.min_rand = rand_area[0]
self.max_rand = rand_area[1]
self.expand_dis = expand_dis
self.goal_sample_rate = goal_sample_rate
self.max_iter = max_iter
self.obstacle_list = obstacle_list
self.node_list = None
def informed_rrt_star_search(self, animation=True):
@@ -46,110 +46,109 @@ class InformedRRTStar:
self.node_list = [self.start]
# max length we expect to find in our 'informed' sample space,
# starts as infinite
cBest = float('inf')
solutionSet = set()
c_best = float('inf')
solution_set = set()
path = None
# Computing the sampling space
cMin = math.sqrt(pow(self.start.x - self.goal.x, 2)
+ pow(self.start.y - self.goal.y, 2))
xCenter = np.array([[(self.start.x + self.goal.x) / 2.0],
[(self.start.y + self.goal.y) / 2.0], [0]])
a1 = np.array([[(self.goal.x - self.start.x) / cMin],
[(self.goal.y - self.start.y) / cMin], [0]])
c_min = math.hypot(self.start.x - self.goal.x,
self.start.y - self.goal.y)
x_center = np.array([[(self.start.x + self.goal.x) / 2.0],
[(self.start.y + self.goal.y) / 2.0], [0]])
a1 = np.array([[(self.goal.x - self.start.x) / c_min],
[(self.goal.y - self.start.y) / c_min], [0]])
e_theta = math.atan2(a1[1], a1[0])
# first column of identity matrix transposed
id1_t = np.array([1.0, 0.0, 0.0]).reshape(1, 3)
M = a1 @ id1_t
U, S, Vh = np.linalg.svd(M, True, True)
C = np.dot(np.dot(U, np.diag(
[1.0, 1.0, np.linalg.det(U) * np.linalg.det(np.transpose(Vh))])),
Vh)
m = a1 @ id1_t
u, s, vh = np.linalg.svd(m, True, True)
c = u @ np.diag(
[1.0, 1.0,
np.linalg.det(u) * np.linalg.det(np.transpose(vh))]) @ vh
for i in range(self.max_iter):
# Sample space is defined by cBest
# cMin is the minimum distance between the start point and the goal
# xCenter is the midpoint between the start and the goal
# cBest changes when a new path is found
# Sample space is defined by c_best
# c_min is the minimum distance between the start point and
# the goal x_center is the midpoint between the start and the
# goal c_best changes when a new path is found
rnd = self.informed_sample(cBest, cMin, xCenter, C)
rnd = self.informed_sample(c_best, c_min, x_center, c)
n_ind = self.get_nearest_list_index(self.node_list, rnd)
nearestNode = self.node_list[n_ind]
nearest_node = self.node_list[n_ind]
# steer
theta = math.atan2(rnd[1] - nearestNode.y, rnd[0] - nearestNode.x)
newNode = self.get_new_node(theta, n_ind, nearestNode)
d = self.line_cost(nearestNode, newNode)
theta = math.atan2(rnd[1] - nearest_node.y,
rnd[0] - nearest_node.x)
new_node = self.get_new_node(theta, n_ind, nearest_node)
d = self.line_cost(nearest_node, new_node)
noCollision = self.check_collision(nearestNode, theta, d)
no_collision = self.check_collision(nearest_node, theta, d)
if noCollision:
nearInds = self.find_near_nodes(newNode)
newNode = self.choose_parent(newNode, nearInds)
if no_collision:
near_inds = self.find_near_nodes(new_node)
new_node = self.choose_parent(new_node, near_inds)
self.node_list.append(newNode)
self.rewire(newNode, nearInds)
self.node_list.append(new_node)
self.rewire(new_node, near_inds)
if self.is_near_goal(newNode):
if self.check_segment_collision(newNode.x, newNode.y,
if self.is_near_goal(new_node):
if self.check_segment_collision(new_node.x, new_node.y,
self.goal.x, self.goal.y):
solutionSet.add(newNode)
lastIndex = len(self.node_list) - 1
tempPath = self.get_final_course(lastIndex)
tempPathLen = self.get_path_len(tempPath)
if tempPathLen < cBest:
path = tempPath
cBest = tempPathLen
solution_set.add(new_node)
last_index = len(self.node_list) - 1
temp_path = self.get_final_course(last_index)
temp_path_len = self.get_path_len(temp_path)
if temp_path_len < c_best:
path = temp_path
c_best = temp_path_len
if animation:
self.draw_graph(xCenter=xCenter,
cBest=cBest, cMin=cMin,
self.draw_graph(x_center=x_center, c_best=c_best, c_min=c_min,
e_theta=e_theta, rnd=rnd)
return path
def choose_parent(self, newNode, nearInds):
if len(nearInds) == 0:
return newNode
def choose_parent(self, new_node, near_inds):
if len(near_inds) == 0:
return new_node
dList = []
for i in nearInds:
dx = newNode.x - self.node_list[i].x
dy = newNode.y - self.node_list[i].y
d_list = []
for i in near_inds:
dx = new_node.x - self.node_list[i].x
dy = new_node.y - self.node_list[i].y
d = math.hypot(dx, dy)
theta = math.atan2(dy, dx)
if self.check_collision(self.node_list[i], theta, d):
dList.append(self.node_list[i].cost + d)
d_list.append(self.node_list[i].cost + d)
else:
dList.append(float('inf'))
d_list.append(float('inf'))
minCost = min(dList)
minInd = nearInds[dList.index(minCost)]
min_cost = min(d_list)
min_ind = near_inds[d_list.index(min_cost)]
if minCost == float('inf'):
if min_cost == float('inf'):
print("min cost is inf")
return newNode
return new_node
newNode.cost = minCost
newNode.parent = minInd
new_node.cost = min_cost
new_node.parent = min_ind
return newNode
return new_node
def find_near_nodes(self, newNode):
def find_near_nodes(self, new_node):
n_node = len(self.node_list)
r = 50.0 * math.sqrt((math.log(n_node) / n_node))
d_list = [(node.x - newNode.x) ** 2 + (node.y - newNode.y) ** 2
for node in self.node_list]
d_list = [(node.x - new_node.x) ** 2 + (node.y - new_node.y) ** 2 for
node in self.node_list]
near_inds = [d_list.index(i) for i in d_list if i <= r ** 2]
return near_inds
def informed_sample(self, cMax, cMin, xCenter, C):
if cMax < float('inf'):
r = [cMax / 2.0,
math.sqrt(cMax ** 2 - cMin ** 2) / 2.0,
math.sqrt(cMax ** 2 - cMin ** 2) / 2.0]
L = np.diag(r)
xBall = self.sample_unit_ball()
rnd = np.dot(np.dot(C, L), xBall) + xCenter
def informed_sample(self, c_max, c_min, x_center, c):
if c_max < float('inf'):
r = [c_max / 2.0, math.sqrt(c_max ** 2 - c_min ** 2) / 2.0,
math.sqrt(c_max ** 2 - c_min ** 2) / 2.0]
rl = np.diag(r)
x_ball = self.sample_unit_ball()
rnd = np.dot(np.dot(c, rl), x_ball) + x_center
rnd = [rnd[(0, 0)], rnd[(1, 0)]]
else:
rnd = self.sample_free_space()
@@ -179,16 +178,15 @@ class InformedRRTStar:
@staticmethod
def get_path_len(path):
pathLen = 0
path_len = 0
for i in range(1, len(path)):
node1_x = path[i][0]
node1_y = path[i][1]
node2_x = path[i - 1][0]
node2_y = path[i - 1][1]
pathLen += math.sqrt((node1_x - node2_x)
** 2 + (node1_y - node2_y) ** 2)
path_len += math.hypot(node1_x - node2_x, node1_y - node2_y)
return pathLen
return path_len
@staticmethod
def line_cost(node1, node2):
@@ -196,20 +194,20 @@ class InformedRRTStar:
@staticmethod
def get_nearest_list_index(nodes, rnd):
dList = [(node.x - rnd[0]) ** 2
+ (node.y - rnd[1]) ** 2 for node in nodes]
minIndex = dList.index(min(dList))
return minIndex
d_list = [(node.x - rnd[0]) ** 2 + (node.y - rnd[1]) ** 2 for node in
nodes]
min_index = d_list.index(min(d_list))
return min_index
def get_new_node(self, theta, n_ind, nearestNode):
newNode = copy.deepcopy(nearestNode)
def get_new_node(self, theta, n_ind, nearest_node):
new_node = copy.deepcopy(nearest_node)
newNode.x += self.expand_dis * math.cos(theta)
newNode.y += self.expand_dis * math.sin(theta)
new_node.x += self.expand_dis * math.cos(theta)
new_node.y += self.expand_dis * math.sin(theta)
newNode.cost += self.expand_dis
newNode.parent = n_ind
return newNode
new_node.cost += self.expand_dis
new_node.parent = n_ind
return new_node
def is_near_goal(self, node):
d = self.line_cost(node, self.goal)
@@ -217,21 +215,21 @@ class InformedRRTStar:
return True
return False
def rewire(self, newNode, nearInds):
def rewire(self, new_node, near_inds):
n_node = len(self.node_list)
for i in nearInds:
nearNode = self.node_list[i]
for i in near_inds:
near_node = self.node_list[i]
d = math.hypot(nearNode.x - newNode.x, nearNode.y - newNode.y)
d = math.hypot(near_node.x - new_node.x, near_node.y - new_node.y)
s_cost = newNode.cost + d
s_cost = new_node.cost + d
if nearNode.cost > s_cost:
theta = math.atan2(newNode.y - nearNode.y,
newNode.x - nearNode.x)
if self.check_collision(nearNode, theta, d):
nearNode.parent = n_node - 1
nearNode.cost = s_cost
if near_node.cost > s_cost:
theta = math.atan2(new_node.y - near_node.y,
new_node.x - near_node.x)
if self.check_collision(near_node, theta, d):
near_node.parent = n_node - 1
near_node.cost = s_cost
@staticmethod
def distance_squared_point_to_segment(v, w, p):
@@ -251,45 +249,44 @@ class InformedRRTStar:
def check_segment_collision(self, x1, y1, x2, y2):
for (ox, oy, size) in self.obstacle_list:
dd = self.distance_squared_point_to_segment(
np.array([x1, y1]),
np.array([x2, y2]),
np.array([ox, oy]))
np.array([x1, y1]), np.array([x2, y2]), np.array([ox, oy]))
if dd <= size ** 2:
return False # collision
return True
def check_collision(self, nearNode, theta, d):
tmpNode = copy.deepcopy(nearNode)
end_x = tmpNode.x + math.cos(theta) * d
end_y = tmpNode.y + math.sin(theta) * d
return self.check_segment_collision(tmpNode.x, tmpNode.y, end_x, end_y)
def check_collision(self, near_node, theta, d):
tmp_node = copy.deepcopy(near_node)
end_x = tmp_node.x + math.cos(theta) * d
end_y = tmp_node.y + math.sin(theta) * d
return self.check_segment_collision(tmp_node.x, tmp_node.y,
end_x, end_y)
def get_final_course(self, lastIndex):
def get_final_course(self, last_index):
path = [[self.goal.x, self.goal.y]]
while self.node_list[lastIndex].parent is not None:
node = self.node_list[lastIndex]
while self.node_list[last_index].parent is not None:
node = self.node_list[last_index]
path.append([node.x, node.y])
lastIndex = node.parent
last_index = node.parent
path.append([self.start.x, self.start.y])
return path
def draw_graph(self, xCenter=None, cBest=None, cMin=None, e_theta=None,
def draw_graph(self, x_center=None, c_best=None, c_min=None, e_theta=None,
rnd=None):
plt.clf()
# for stopping simulation with the esc key.
plt.gcf().canvas.mpl_connect(
'key_release_event',
lambda event: [exit(0) if event.key == 'escape' else None])
'key_release_event', lambda event:
[exit(0) if event.key == 'escape' else None])
if rnd is not None:
plt.plot(rnd[0], rnd[1], "^k")
if cBest != float('inf'):
self.plot_ellipse(xCenter, cBest, cMin, e_theta)
if c_best != float('inf'):
self.plot_ellipse(x_center, c_best, c_min, e_theta)
for node in self.node_list:
if node.parent is not None:
if node.x or node.y is not None:
plt.plot([node.x, self.node_list[node.parent].x], [
node.y, self.node_list[node.parent].y], "-g")
plt.plot([node.x, self.node_list[node.parent].x],
[node.y, self.node_list[node.parent].y], "-g")
for (ox, oy, size) in self.obstacle_list:
plt.plot(ox, oy, "ok", ms=30 * size)
@@ -301,13 +298,13 @@ class InformedRRTStar:
plt.pause(0.01)
@staticmethod
def plot_ellipse(xCenter, cBest, cMin, e_theta): # pragma: no cover
def plot_ellipse(x_center, c_best, c_min, e_theta): # pragma: no cover
a = math.sqrt(cBest ** 2 - cMin ** 2) / 2.0
b = cBest / 2.0
a = math.sqrt(c_best ** 2 - c_min ** 2) / 2.0
b = c_best / 2.0
angle = math.pi / 2.0 - e_theta
cx = xCenter[0]
cy = xCenter[1]
cx = x_center[0]
cy = x_center[1]
t = np.arange(0, 2 * math.pi + 0.1, 0.1)
x = [a * math.cos(it) for it in t]
y = [b * math.sin(it) for it in t]
@@ -331,18 +328,12 @@ def main():
print("Start informed rrt star planning")
# create obstacles
obstacleList = [
(5, 5, 0.5),
(9, 6, 1),
(7, 5, 1),
(1, 5, 1),
(3, 6, 1),
(7, 9, 1)
]
obstacle_list = [(5, 5, 0.5), (9, 6, 1), (7, 5, 1), (1, 5, 1), (3, 6, 1),
(7, 9, 1)]
# Set params
rrt = InformedRRTStar(start=[0, 0], goal=[5, 10],
randArea=[-2, 15], obstacleList=obstacleList)
rrt = InformedRRTStar(start=[0, 0], goal=[5, 10], rand_area=[-2, 15],
obstacle_list=obstacle_list)
path = rrt.informed_rrt_star_search(animation=show_animation)
print("Done!!")