1. 场景描述
如下图所示，自车（蓝车）与前车（白车）在同一车道行驶， 自车初速度为 27m/s，前车以22m/s的速度匀速行驶，两车相距 80m：
目标：自车通过换道，超越前车
2. 代码实现
这里的强化学习采用的是基于stable-baseline3所集成的PPO算法，算法可参考该博客Proximal Policy Optimization近端策略优化（PPO）。
环境初始化测试的代码可见博客highway-env自定义高速路环境
2.1 依赖包版本
gym == 0.21.0
highway-env == 1.5
stable-baselines3 == 1.6.2
2.2 代码
模型训练：
"""
@Author: Fhz
@Create Date: 2023/3/23 22:15
@File: rewrite_Fhz.py
@Description:
@Modify Person Date:
"""
import highway_env
from highway_env.envs.common.abstract import AbstractEnv
from highway_env.road.road import Road, RoadNetwork
from highway_env.envs.common.action import Action
from highway_env.vehicle.controller import ControlledVehicle
from highway_env.vehicle.kinematics import Vehicle
from stable_baselines3 import PPO
import numpy as np
LANES = 2
ANGLE = 0
START = 0
LENGHT = 200
SPEED_LIMIT = 30
SPEED_REWARD_RANGE = [10, 30]
COL_REWARD = -1
HIGH_SPEED_REWARD = 0
RIGHT_LANE_REWARD = 0
DURATION = 500.0
class myEnv(AbstractEnv):
@classmethod
def default_config(cls) -> dict:
config = super().default_config()
config.update(
{
'observation': {
'type': 'Kinematics',
"absolute": True,
"normalize": False,
},
'action': {'type': 'DiscreteMetaAction',
'target_speeds': np.array([10,20,30]) # 目标速度设置
},
"features": ["x", "y", "vx", "vy"],
"features_range": {
"x": [-10000, 10000],
"y": [-10000, 10000],
"vx": [-10, 10],
"vy": [-10, 30]},
"reward_speed_range": SPEED_REWARD_RANGE,
"simulation_frequency": 20,
"policy_frequency": 20,
'screen_width': 1200,
'screen_height': 150,
# "other_vehicles": 5,
# "centering_position": [0.3, 0.5],
}
)
return config
def _reset(self) -> None:
self._create_road()
self._create_vehicles()
def _create_road(self) -> None:
self.road = Road(
network=RoadNetwork.straight_road_network(LANES, speed_limit=SPEED_LIMIT),
np_random=self.np_random,
record_history=False,
)
# 创建车辆
def _create_vehicles(self) -> None:
# 自车
vehicle = Vehicle.create_random(self.road, speed=27, lane_id=1, spacing=0.3)
vehicle = self.action_type.vehicle_class(
self.road,
vehicle.position,
vehicle.heading,
vehicle.speed,
)
self.vehicle = vehicle
self.road.vehicles.append(vehicle)
# 周围车辆1
vehicle = Vehicle.create_random(self.road, speed=22, lane_id=1, spacing=0.35)
vehicle = self.action_type.vehicle_class(
self.road,
vehicle.position + [75,0], # 初始化目标场景，不加这一项的话，默认距离为5
vehicle.heading,
vehicle.speed,
)
self.road.vehicles.append(vehicle)
vehicle.color = (255, 255, 255)
# 重写的奖励函数
def _reward(self, action: Action) -> float:
reward_all = 0
# 速度奖励，通过惩罚使得最低车速为20
r_speed = (1/10) * (self.vehicle.speed - 20)
# 目标车道奖励
ego_lane = self.vehicle.lane_index[2]
if ego_lane == 1:
r_target_lane = 0
else:
r_target_lane = 0.1
# 碰撞后奖励
if self.vehicle.crashed:
print("撞上了！")
r_collsion = -180
else:
r_collsion = 0
# 车辆横向位移偏出车道奖励
r_out = 0
r_change_lane = 0
ego_pos_x = self.vehicle.position[1]
if ego_pos_x > 4 and ego_pos_x < 0:
r_target_lane = 0
r_out = -200
print("车离开车道！")
self.vehicle.crashed = True # 与路沿碰撞
return r_speed + r_out + r_collsion + r_target_lane
reward_all = r_speed + r_out + r_collsion + r_target_lane
return reward_all
def _is_terminal(self) -> bool:
# return (
# self.vehicle.crashed
# or self.time >= DURATION
# or (False and not self.vehicle.on_road)
# )
if self.vehicle.crashed:
return True
if self.time >= DURATION:
print("时间到了！")
return True
if False and not self.vehicle.on_road:
print("车不在路上了！")
return True
return False
if __name__ == '__main__':
env = myEnv()
model = PPO('MlpPolicy', env,
policy_kwargs=dict(net_arch=[256, 256]),
learning_rate=5e-4,
batch_size=32,
gamma=0.8,
verbose=1,
tensorboard_log="highway_dqn/")
model.learn(int(1e5))
model.save("highway_dqn/PPOmodel")
训练结果：
模型测试代码：
"""
@Author: Fhz
@Create Date: 2023/3/23 22:15
@File: rewrite_Fhz.py
@Description:
@Modify Person Date:
"""
import highway_env
from highway_env.envs.common.abstract import AbstractEnv
from highway_env.road.road import Road, RoadNetwork
from highway_env.envs.common.action import Action
from highway_env.vehicle.controller import ControlledVehicle
from highway_env.vehicle.kinematics import Vehicle
from stable_baselines3 import PPO
import numpy as np
LANES = 2
ANGLE = 0
START = 0
LENGHT = 200
SPEED_LIMIT = 30
SPEED_REWARD_RANGE = [10, 30]
COL_REWARD = -1
HIGH_SPEED_REWARD = 0
RIGHT_LANE_REWARD = 0
DURATION = 500.0
class myEnv(AbstractEnv):
@classmethod
def default_config(cls) -> dict:
config = super().default_config()
config.update(
{
'observation': {
'type': 'Kinematics',
"absolute": True,
"normalize": False,
},
'action': {'type': 'DiscreteMetaAction',
'target_speeds': np.array([10,20,30]) # 目标速度设置
},
"features": ["x", "y", "vx", "vy"],
"features_range": {
"x": [-10000, 10000],
"y": [-10000, 10000],
"vx": [-10, 10],
"vy": [-10, 30]},
"reward_speed_range": SPEED_REWARD_RANGE,
"simulation_frequency": 20,
"policy_frequency": 20,
'screen_width': 1200,
'screen_height': 150,
# "other_vehicles": 5,
# "centering_position": [0.3, 0.5],
}
)
return config
def _reset(self) -> None:
self._create_road()
self._create_vehicles()
def _create_road(self) -> None:
self.road = Road(
network=RoadNetwork.straight_road_network(LANES, speed_limit=SPEED_LIMIT),
np_random=self.np_random,
record_history=False,
)
# 创建车辆
def _create_vehicles(self) -> None:
# 自车
vehicle = Vehicle.create_random(self.road, speed=27, lane_id=1, spacing=0.3)
vehicle = self.action_type.vehicle_class(
self.road,
vehicle.position,
vehicle.heading,
vehicle.speed,
)
self.vehicle = vehicle
self.road.vehicles.append(vehicle)
# 周围车辆1
vehicle = Vehicle.create_random(self.road, speed=22, lane_id=1, spacing=0.35)
vehicle = self.action_type.vehicle_class(
self.road,
vehicle.position + [75,0], # 初始化目标场景，不加这一项的话，默认距离为5
vehicle.heading,
vehicle.speed,
)
self.road.vehicles.append(vehicle)
vehicle.color = (255, 255, 255)
# 重写的奖励函数
def _reward(self, action: Action) -> float:
reward_all = 0
# 速度奖励，通过惩罚使得最低车速为20
r_speed = (1/10) * (self.vehicle.speed - 20)
# 目标车道奖励
ego_lane = self.vehicle.lane_index[2]
if ego_lane == 1:
r_target_lane = 0
else:
r_target_lane = 0.1
# 碰撞后奖励
if self.vehicle.crashed:
print("撞上了！")
r_collsion = -180
else:
r_collsion = 0
# 车辆横向位移偏出车道奖励
r_out = 0
r_change_lane = 0
ego_pos_x = self.vehicle.position[1]
if ego_pos_x > 4 and ego_pos_x < 0:
r_target_lane = 0
r_out = -200
print("车离开车道！")
self.vehicle.crashed = True # 与路沿碰撞
return r_speed + r_out + r_collsion + r_target_lane
reward_all = r_speed + r_out + r_collsion + r_target_lane
return reward_all
def _is_terminal(self) -> bool:
# return (
# self.vehicle.crashed
# or self.time >= DURATION
# or (False and not self.vehicle.on_road)
# )
if self.vehicle.crashed:
return True
if self.time >= DURATION:
print("时间到了！")
return True
if False and not self.vehicle.on_road:
print("车不在路上了！")
return True
return False
if __name__ == '__main__':
env = myEnv()
model = PPO.load("highway_dqn/PPOmodel", env=env)
eposides = 10
for eq in range(eposides):
obs = env.reset()
env.render()
rewards = 0
done = False
while not done:
# action = env.action_space.sample()
action, _state = model.predict(obs, deterministic=True)
action = action.item()
print("The action is: {}".format(action))
obs, reward, done, info = env.step(action)
print("The speed of ego vehicle: {}, other vehicle: {}".format(obs[0, 3], obs[1, 3]))
env.render()
rewards += reward
print(rewards)
验证视频为：视频文章来源：https://www.toymoban.com/news/detail-775517.html
3. 相关资料
highway-env手册：地址
highway-env自定义高速路环境
基于强化学习A2C快速路车辆决策控制
基于DQN强化学习的高速路决策控制文章来源地址https://www.toymoban.com/news/detail-775517.html
到了这里，关于基于PPO自定义highway-env场景的车辆换道决策的文章就介绍完了。如果您还想了解更多内容，请在右上角搜索TOY模板网以前的文章或继续浏览下面的相关文章，希望大家以后多多支持TOY模板网！
