Files
PythonRobotics/PathPlanning/RRTDubins/rrt_dubins.py
2018-10-23 21:49:08 +09:00

252 lines
6.7 KiB
Python

"""
Path Planning Sample Code with RRT for car like robot.
author: AtsushiSakai(@Atsushi_twi)
"""
import random
import math
import copy
import numpy as np
import dubins_path_planning
import matplotlib.pyplot as plt
show_animation = True
class RRT():
"""
Class for RRT Planning
"""
def __init__(self, start, goal, obstacleList, randArea,
goalSampleRate=10, maxIter=1000):
"""
Setting Parameter
start:Start Position [x,y]
goal:Goal Position [x,y]
obstacleList:obstacle Positions [[x,y,size],...]
randArea:Ramdom Samping Area [min,max]
"""
self.start = Node(start[0], start[1], start[2])
self.end = Node(goal[0], goal[1], goal[2])
self.minrand = randArea[0]
self.maxrand = randArea[1]
self.goalSampleRate = goalSampleRate
self.maxIter = maxIter
self.obstacleList = obstacleList
def Planning(self, animation=False):
"""
Pathplanning
animation: flag for animation on or off
"""
self.nodeList = [self.start]
for i in range(self.maxIter):
rnd = self.get_random_point()
nind = self.GetNearestListIndex(self.nodeList, rnd)
newNode = self.steer(rnd, nind)
if self.__CollisionCheck(newNode, self.obstacleList):
self.nodeList.append(newNode)
if animation and i % 5 == 0:
self.DrawGraph(rnd=rnd)
# generate coruse
lastIndex = self.get_best_last_index()
# print(lastIndex)
if lastIndex is None:
return None
path = self.gen_final_course(lastIndex)
return path
def choose_parent(self, newNode, nearinds):
if len(nearinds) == 0:
return newNode
dlist = []
for i in nearinds:
dx = newNode.x - self.nodeList[i].x
dy = newNode.y - self.nodeList[i].y
d = math.sqrt(dx ** 2 + dy ** 2)
theta = math.atan2(dy, dx)
if self.check_collision_extend(self.nodeList[i], theta, d):
dlist.append(self.nodeList[i].cost + d)
else:
dlist.append(float("inf"))
mincost = min(dlist)
minind = nearinds[dlist.index(mincost)]
if mincost == float("inf"):
print("mincost is inf")
return newNode
newNode.cost = mincost
newNode.parent = minind
return newNode
def pi_2_pi(self, angle):
return (angle + math.pi) % (2 * math.pi) - math.pi
def steer(self, rnd, nind):
# print(rnd)
curvature = 1.0
nearestNode = self.nodeList[nind]
px, py, pyaw, mode, clen = dubins_path_planning.dubins_path_planning(
nearestNode.x, nearestNode.y, nearestNode.yaw, rnd[0], rnd[1], rnd[2], curvature)
newNode = copy.deepcopy(nearestNode)
newNode.x = px[-1]
newNode.y = py[-1]
newNode.yaw = pyaw[-1]
newNode.path_x = px
newNode.path_y = py
newNode.path_yaw = pyaw
newNode.cost += clen
newNode.parent = nind
return newNode
def get_random_point(self):
if random.randint(0, 100) > self.goalSampleRate:
rnd = [random.uniform(self.minrand, self.maxrand),
random.uniform(self.minrand, self.maxrand),
random.uniform(-math.pi, math.pi)
]
else: # goal point sampling
rnd = [self.end.x, self.end.y, self.end.yaw]
return rnd
def get_best_last_index(self):
# print("get_best_last_index")
disglist = [self.calc_dist_to_goal(
node.x, node.y) for node in self.nodeList]
goalinds = [disglist.index(i) for i in disglist if i <= 0.1]
# print(goalinds)
mincost = min([self.nodeList[i].cost for i in goalinds])
for i in goalinds:
if self.nodeList[i].cost == mincost:
return i
return None
def gen_final_course(self, goalind):
path = [[self.end.x, self.end.y]]
while self.nodeList[goalind].parent is not None:
node = self.nodeList[goalind]
for (ix, iy) in zip(reversed(node.path_x), reversed(node.path_y)):
path.append([ix, iy])
# path.append([node.x, node.y])
goalind = node.parent
path.append([self.start.x, self.start.y])
return path
def calc_dist_to_goal(self, x, y):
return np.linalg.norm([x - self.end.x, y - self.end.y])
def DrawGraph(self, rnd=None):
plt.clf()
if rnd is not None:
plt.plot(rnd[0], rnd[1], "^k")
for node in self.nodeList:
if node.parent is not None:
plt.plot(node.path_x, node.path_y, "-g")
for (ox, oy, size) in self.obstacleList:
plt.plot(ox, oy, "ok", ms=30 * size)
dubins_path_planning.plot_arrow(
self.start.x, self.start.y, self.start.yaw)
dubins_path_planning.plot_arrow(
self.end.x, self.end.y, self.end.yaw)
plt.axis([-2, 15, -2, 15])
plt.grid(True)
plt.pause(0.01)
def GetNearestListIndex(self, nodeList, rnd):
dlist = [(node.x - rnd[0]) ** 2 +
(node.y - rnd[1]) ** 2 +
(node.yaw - rnd[2] ** 2) for node in nodeList]
minind = dlist.index(min(dlist))
return minind
def __CollisionCheck(self, node, obstacleList):
for (ox, oy, size) in obstacleList:
for (ix, iy) in zip(node.path_x, node.path_y):
dx = ox - ix
dy = oy - iy
d = dx * dx + dy * dy
if d <= size ** 2:
return False # collision
return True # safe
class Node():
"""
RRT Node
"""
def __init__(self, x, y, yaw):
self.x = x
self.y = y
self.yaw = yaw
self.path_x = []
self.path_y = []
self.path_yaw = []
self.cost = 0.0
self.parent = None
def main():
print("Start rrt planning")
# ====Search Path with RRT====
obstacleList = [
(5, 5, 1),
(3, 6, 2),
(3, 8, 2),
(3, 10, 2),
(7, 5, 2),
(9, 5, 2)
] # [x,y,size(radius)]
# Set Initial parameters
start = [0.0, 0.0, np.deg2rad(0.0)]
goal = [10.0, 10.0, np.deg2rad(0.0)]
rrt = RRT(start, goal, randArea=[-2.0, 15.0], obstacleList=obstacleList)
path = rrt.Planning(animation=show_animation)
# Draw final path
if show_animation:
rrt.DrawGraph()
plt.plot([x for (x, y) in path], [y for (x, y) in path], '-r')
plt.grid(True)
plt.pause(0.001)
plt.show()
if __name__ == '__main__':
main()