gym中机器人找金币环境侯建

ゞ浴缸里的玫瑰 2022-11-17 03:51 54阅读 0赞

# 一、目标 #

接下来要做个一个游戏是找金币，如下图所示，一个机器人从地图空白位置随机产生，通过上下左右移动，到达金币位置胜利，遇到了两个陷阱则失败，本文是构建了该地图并将地图注册到gym中，方便以后使用标准方法调用

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNjg1MjY1_size_16_color_FFFFFF_t_70][]

# 二、构建过程 #

首先定义**状态空间、动作空间、回报函数与状态转移概率**

#状态空间
    self.states = [1,2,3,4,5,6,7,8]
    
    #机器人可能产生的位置
    self.x=[140,220,300,380,460,140,300,460]
    self.y=[250,250,250,250,250,150,150,150]
    
    
    self.terminate_states = dict()  #终止状态为字典格式
    self.terminate_states[6] = 1
    self.terminate_states[7] = 1
    self.terminate_states[8] = 1
    
    #机器人可以进行的动作
    self.actions = ['n','e','s','w']
    
    #回报的数据结构为字典
    self.rewards = dict();        
    self.rewards['1_s'] = -1.0
    self.rewards['3_s'] = 1.0
    self.rewards['5_s'] = -1.0
    
    #状态转移的数据格式为字典
    self.t = dict();             
    self.t['1_s'] = 6
    self.t['1_e'] = 2
    self.t['2_w'] = 1
    self.t['2_e'] = 3
    self.t['3_s'] = 7
    self.t['3_w'] = 2
    self.t['3_e'] = 4
    self.t['4_w'] = 3
    self.t['4_e'] = 5
    self.t['5_s'] = 8
    self.t['5_w'] = 4
    
    #折扣因子
    self.gamma = 0.8         
    self.viewer = None
    self.state = None

下边要定义三个标准调用函数：step、reset、render:

**step是根据当前机器人的位置和动作action，计算下一状态**

def _step(self, action):
        #系统当前状态
        state = self.state
        if state in self.terminate_states:
            return state, 0, True, {}
        key = "%d_%s"%(state, action)   #将状态和动作组成字典的键值
    
        #状态转移
        if key in self.t:
            next_state = self.t[key]
        else:
            next_state = state
        self.state = next_state
    
        is_terminal = False
    
        if next_state in self.terminate_states:
            is_terminal = True
    
        if key not in self.rewards:
            r = 0.0
        else:
            r = self.rewards[key]

**reset是初始化**

def _reset(self):
        self.state = self.states[int(random.random() * len(self.states))]
        return self.state

**render是更新界面，里边很长的代码是用来画界面的，用线和圆圈来代表地图和机器人、陷阱、金币**

def render(self, mode='human', close=False):
        if close:
            if self.viewer is not None:
                self.viewer.close()
                self.viewer = None
            return
        screen_width = 600
        screen_height = 400
    
        if self.viewer is None:
            from gym.envs.classic_control import rendering
            self.viewer = rendering.Viewer(screen_width, screen_height)
            #创建网格世界
            self.line1 = rendering.Line((100,300),(500,300))
            self.line2 = rendering.Line((100, 200), (500, 200))
            self.line3 = rendering.Line((100, 300), (100, 100))
            self.line4 = rendering.Line((180, 300), (180, 100))
            self.line5 = rendering.Line((260, 300), (260, 100))
            self.line6 = rendering.Line((340, 300), (340, 100))
            self.line7 = rendering.Line((420, 300), (420, 100))
            self.line8 = rendering.Line((500, 300), (500, 100))
            self.line9 = rendering.Line((100, 100), (180, 100))
            self.line10 = rendering.Line((260, 100), (340, 100))
            self.line11 = rendering.Line((420, 100), (500, 100))
            #创建第一个骷髅
            self.kulo1 = rendering.make_circle(40)
            self.circletrans = rendering.Transform(translation=(140,150))
            self.kulo1.add_attr(self.circletrans)
            self.kulo1.set_color(0,0,0)
            #创建第二个骷髅
            self.kulo2 = rendering.make_circle(40)
            self.circletrans = rendering.Transform(translation=(460, 150))
            self.kulo2.add_attr(self.circletrans)
            self.kulo2.set_color(0, 0, 0)
            #创建金条
            self.gold = rendering.make_circle(40)
            self.circletrans = rendering.Transform(translation=(300, 150))
            self.gold.add_attr(self.circletrans)
            self.gold.set_color(1, 0.9, 0)
            #创建机器人
            self.robot= rendering.make_circle(30)
            self.robotrans = rendering.Transform()
            self.robot.add_attr(self.robotrans)
            self.robot.set_color(0.8, 0.6, 0.4)
    
            self.line1.set_color(0, 0, 0)
            self.line2.set_color(0, 0, 0)
            self.line3.set_color(0, 0, 0)
            self.line4.set_color(0, 0, 0)
            self.line5.set_color(0, 0, 0)
            self.line6.set_color(0, 0, 0)
            self.line7.set_color(0, 0, 0)
            self.line8.set_color(0, 0, 0)
            self.line9.set_color(0, 0, 0)
            self.line10.set_color(0, 0, 0)
            self.line11.set_color(0, 0, 0)
    
            self.viewer.add_geom(self.line1)
            self.viewer.add_geom(self.line2)
            self.viewer.add_geom(self.line3)
            self.viewer.add_geom(self.line4)
            self.viewer.add_geom(self.line5)
            self.viewer.add_geom(self.line6)
            self.viewer.add_geom(self.line7)
            self.viewer.add_geom(self.line8)
            self.viewer.add_geom(self.line9)
            self.viewer.add_geom(self.line10)
            self.viewer.add_geom(self.line11)
            self.viewer.add_geom(self.kulo1)
            self.viewer.add_geom(self.kulo2)
            self.viewer.add_geom(self.gold)
            self.viewer.add_geom(self.robot)
    
        if self.state is None: return None
        #self.robotrans.set_translation(self.x[self.state-1],self.y[self.state-1])
        self.robotrans.set_translation(self.x[self.state-1], self.y[self.state- 1])
    
    
    
        return self.viewer.render(return_rgb_array=mode == 'rgb_array')

这样就完成了构建的主体，全部代码可以看**链接**：[https://paste.ubuntu.com/p/XP8xbz6kJv/][https_paste.ubuntu.com_p_XP8xbz6kJv]

# 三、环境注册 #

注册是为了将构建好的游戏地图保存并以gym的标准调用方式调用：

1、将上述代码所在的.py文件拷到gym安装目录/gym/gym/envs/classic\_control文件夹下

2、在文件夹的\_\_init\_\_.py中，末尾加入：其中XXX就是上述你的文件名

from gym.envs.classic_control.XXX import GridEnv

3、在/gym/gym/envs中，打开\_\_init\_\_.py文件，添加代码：

register(
        id = 'GridWorld-v0',
        entry_point = 'gym.envs.classic_control:GridEnv',
        max_episode_steps = 200,
        reward_threshold = 100.0,
    )

第一个参数id就是gym.make(‘id’)中的id，可以根据情况改，这样就完成了注册

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNjg1MjY1_size_16_color_FFFFFF_t_70]: /images/20221022/73c5321f9b1f49f3ad36bffeb34af4db.png
[https_paste.ubuntu.com_p_XP8xbz6kJv]: https://paste.ubuntu.com/p/XP8xbz6kJv/