mirror of
https://github.com/zhm-real/PathPlanning.git
synced 2026-08-29 16:40:46 +08:00
update D*
This commit is contained in:
zhm-real
@@ -50,10 +50,12 @@ class DStar:
|
||||
def run(self, s_start, s_end):
|
||||
self.init()
|
||||
self.insert(s_end, 0)
|
||||
|
||||
while True:
|
||||
self.process_state()
|
||||
if self.t[s_start] == 'CLOSED':
|
||||
break
|
||||
|
||||
self.path = self.extract_path(s_start, s_end)
|
||||
self.Plot.plot_grid("Dynamic A* (D*)")
|
||||
self.plot_path(self.path)
|
||||
@@ -66,22 +68,28 @@ class DStar:
|
||||
print("Please choose right area!")
|
||||
else:
|
||||
x, y = int(x), int(y)
|
||||
print("Add obstacle at: s =", x, ",", "y =", y)
|
||||
self.obs.add((x, y))
|
||||
plt.plot(x, y, 'sk')
|
||||
s = self.s_start
|
||||
self.visited = set()
|
||||
self.count += 1
|
||||
if (x, y) not in self.obs:
|
||||
print("Add obstacle at: s =", x, ",", "y =", y)
|
||||
self.obs.add((x, y))
|
||||
self.Plot.update_obs(self.obs)
|
||||
|
||||
while s != self.s_goal:
|
||||
if self.is_collision(s, self.PARENT[s]):
|
||||
self.modify(s)
|
||||
continue
|
||||
s = self.PARENT[s]
|
||||
s = self.s_start
|
||||
self.visited = set()
|
||||
self.count += 1
|
||||
|
||||
while s != self.s_goal:
|
||||
if self.is_collision(s, self.PARENT[s]):
|
||||
self.modify(s)
|
||||
continue
|
||||
s = self.PARENT[s]
|
||||
|
||||
self.path = self.extract_path(self.s_start, self.s_goal)
|
||||
|
||||
plt.cla()
|
||||
self.Plot.plot_grid("Dynamic A* (D*)")
|
||||
self.plot_visited(self.visited)
|
||||
self.plot_path(self.path)
|
||||
|
||||
self.path = self.extract_path(self.s_start, self.s_goal)
|
||||
self.plot_visited(self.visited)
|
||||
self.plot_path(self.path)
|
||||
self.fig.canvas.draw_idle()
|
||||
|
||||
def extract_path(self, s_start, s_end):
|
||||
@@ -94,42 +102,63 @@ class DStar:
|
||||
return path
|
||||
|
||||
def process_state(self):
|
||||
s = self.min_state()
|
||||
s = self.min_state() # get node in OPEN set with min k value
|
||||
self.visited.add(s)
|
||||
|
||||
if s is None:
|
||||
return -1
|
||||
return -1 # OPEN set is empty
|
||||
|
||||
k_old = self.get_k_min()
|
||||
self.delete(s)
|
||||
k_old = self.get_k_min() # record the min k value of this iteration (min path cost)
|
||||
self.delete(s) # move state s from OPEN set to CLOSED set
|
||||
|
||||
# k_min < h[s] --> s: RAISE state (increased cost)
|
||||
if k_old < self.h[s]:
|
||||
for s_n in self.get_neighbor(s):
|
||||
if self.h[s_n] <= k_old and self.h[s] > self.h[s_n] + self.cost(s_n, s):
|
||||
if self.h[s_n] <= k_old and \
|
||||
self.h[s] > self.h[s_n] + self.cost(s_n, s):
|
||||
|
||||
# update h_value and choose parent
|
||||
self.PARENT[s] = s_n
|
||||
self.h[s] = self.h[s_n] + self.cost(s_n, s)
|
||||
|
||||
# s: k_min >= h[s] -- > s: LOWER state (cost reductions)
|
||||
if k_old == self.h[s]:
|
||||
for s_n in self.get_neighbor(s):
|
||||
if self.t[s_n] == 'NEW' or \
|
||||
(self.PARENT[s_n] == s and self.h[s_n] != self.h[s] + self.cost(s, s_n)) or \
|
||||
(self.PARENT[s_n] != s and self.h[s_n] > self.h[s] + self.cost(s, s_n)):
|
||||
|
||||
# Condition:
|
||||
# 1) t[s_n] == 'NEW': not visited
|
||||
# 2) s_n's parent: cost reduction
|
||||
# 3) s_n find a better parent
|
||||
self.PARENT[s_n] = s
|
||||
self.insert(s_n, self.h[s] + self.cost(s, s_n))
|
||||
else:
|
||||
for s_n in self.get_neighbor(s):
|
||||
if self.t[s_n] == 'NEW' or \
|
||||
(self.PARENT[s_n] == s and self.h[s_n] != self.h[s] + self.cost(s, s_n)):
|
||||
|
||||
# Condition:
|
||||
# 1) t[s_n] == 'NEW': not visited
|
||||
# 2) s_n's parent: cost reduction
|
||||
self.PARENT[s_n] = s
|
||||
self.insert(s_n, self.h[s] + self.cost(s, s_n))
|
||||
else:
|
||||
if self.PARENT[s_n] != s and self.h[s_n] > self.h[s] + self.cost(s, s_n):
|
||||
if self.PARENT[s_n] != s and \
|
||||
self.h[s_n] > self.h[s] + self.cost(s, s_n):
|
||||
|
||||
# Condition: LOWER happened in OPEN set (s), s should be explored again
|
||||
self.insert(s, self.h[s])
|
||||
else:
|
||||
if self.PARENT[s_n] != s and \
|
||||
self.h[s] > self.h[s_n] + self.cost(s_n, s) and \
|
||||
self.t[s_n] == 'CLOSED' and \
|
||||
self.h[s_n] > k_old:
|
||||
|
||||
# Condition: LOWER happened in CLOSED set (s_n), s_n should be explored again
|
||||
self.insert(s_n, self.h[s_n])
|
||||
|
||||
return self.get_k_min()
|
||||
|
||||
def min_state(self):
|
||||
@@ -155,6 +184,12 @@ class DStar:
|
||||
return min([self.k[x] for x in self.OPEN])
|
||||
|
||||
def insert(self, s, h_new):
|
||||
"""
|
||||
insert node into OPEN set.
|
||||
:param s: node
|
||||
:param h_new: new or better cost to come value
|
||||
"""
|
||||
|
||||
if self.t[s] == 'NEW':
|
||||
self.k[s] = h_new
|
||||
elif self.t[s] == 'OPEN':
|
||||
@@ -178,13 +213,23 @@ class DStar:
|
||||
self.OPEN.remove(s)
|
||||
|
||||
def modify(self, s):
|
||||
"""
|
||||
start processing from state s.
|
||||
:param s: is a node whose status is RAISE or LOWER.
|
||||
"""
|
||||
|
||||
self.modify_cost(s)
|
||||
|
||||
while True:
|
||||
k_min = self.process_state()
|
||||
|
||||
if k_min >= self.h[s]:
|
||||
break
|
||||
|
||||
def modify_cost(self, s):
|
||||
# if node in CLOSED set, put it into OPEN set.
|
||||
# Since cost may be changed between s - s.parent, calc cost(s, s.p) again
|
||||
|
||||
if self.t[s] == 'CLOSED':
|
||||
self.insert(s, self.h[self.PARENT[s]] + self.cost(s, self.PARENT[s]))
|
||||
|
||||
|
||||
Binary file not shown.
Binary file not shown.
@@ -12,6 +12,9 @@ class Env:
|
||||
(1, 0), (1, -1), (0, -1), (-1, -1)]
|
||||
self.obs = self.obs_map()
|
||||
|
||||
def update_obs(self, obs):
|
||||
self.obs = obs
|
||||
|
||||
def obs_map(self):
|
||||
"""
|
||||
Initialize obstacles' positions
|
||||
|
||||
@@ -19,6 +19,9 @@ class Plotting:
|
||||
self.env = env.Env()
|
||||
self.obs = self.env.obs_map()
|
||||
|
||||
def update_obs(self, obs):
|
||||
self.obs = obs
|
||||
|
||||
def animation(self, path, visited, name):
|
||||
self.plot_grid(name)
|
||||
self.plot_visited(visited)
|
||||
|
||||
Reference in New Issue
Block a user