使用路径规划(Dijkstra)在迷宫中导航



我正在研究一种机器人,它将能够在迷宫中导航,避开障碍物并识别其中的一些物体。我有一个迷宫的单色位图,应该在机器人导航中使用。

到目前为止,我已经处理了位图图像,并将其转换为邻接表。现在我将使用dijkstra的算法来规划路径。

然而,问题是我必须从bmp图像本身提取入口点/节点和出口节点,以便dijkstra的算法来规划路径。

机器人的起始位置将与迷宫的入口点略有不同(在入口点前一两英寸),我应该使用任何"任意方法"移动到入口点,然后应用dijkstra算法规划从迷宫入口到出口的路径。

在路上,我也必须停止在"X"标记的bmp文件,我附在下面。这些X基本上是盒子,我必须在里面装球。我将规划从入口点到出口点的路径,而不是从入口到第一个盒子,然后到第二个盒子,然后到出口点;因为我认为盒子总是会被放置在最短路径上。

由于起始位置与入口点不同,我如何将我的机器人的物理位置与程序中的坐标匹配并相应地移动它?即使入口位置与起始位置相同,也可能存在错误。我该怎么处理呢?我应该只在dijkstra提供的坐标的基础上导航,还是使用超声波来防止碰撞?如果我们可以,你能告诉我如何使用这两种方法(超声波和坐标)吗?

这是迷宫的样例位图图像

我知道你需要这个机器人,但这里有一个例子如何在java中转换像素到数组给一些想法?

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.Timer;
import javax.swing.WindowConstants;
public class RobotDemo extends JFrame {
    private static final long serialVersionUID = 1L;

    public RobotDemo() {
        super("Robot Demo");
        setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        getContentPane().add(new RobotPanel(), BorderLayout.CENTER);
        pack();
        setResizable(false);
        setLocationRelativeTo(null);        
    }
    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                JFrame frame = new RobotDemo();
                frame.setVisible(true);
            }
        });     
    }
}
interface Constants {
    public static final int TILE_WIDTH = 32;
    public static final int TILE_HEIGHT = 32;
    public static final int NUM_TILE_COLS = 20;
    public static final int NUM_TILE_ROWS = 10;
    public static final int PIXEL_STEPS = 3;
    public static final int REFRESH_RATE = 200;
    public static final Dimension PANEL_SIZE = new Dimension(TILE_WIDTH * NUM_TILE_COLS, TILE_HEIGHT * NUM_TILE_ROWS);  
    public static enum RobotState {
        awaiting_instruction,
        moving_north,
        moving_south,
        moving_east,
        moving_west     
    };
    public static enum RobotInstruction {
        NORTH,
        SOUTH,
        EAST,
        WEST    
    }
    public void draw(Graphics g);
}
class RobotPanel extends JPanel implements Constants, ActionListener {
    private static final long serialVersionUID = 1L;    
    private Timer timer = new Timer(REFRESH_RATE, this);
    private Map map = new Map();
    private Robot robot = new Robot(map);
    public RobotPanel() {
        timer.start();
    }
    public Dimension getPreferredSize() { return PANEL_SIZE; }
    public Dimension getMinimumSize() { return PANEL_SIZE; }
    public Dimension getMaximumSize() { return PANEL_SIZE; }
    protected void paintComponent(Graphics g) {
        super.paintComponent(g);        
        map.draw(g);
        robot.draw(g);
        draw(g);
    }
    public void actionPerformed(ActionEvent e) {
        robot.update(); 
        repaint();
    }
    public void draw(Graphics g) {
        for(int r = 0; r < NUM_TILE_ROWS; r++) {
            for(int c = 0; c < NUM_TILE_COLS; c++) {
                g.drawRect(c * TILE_WIDTH, r * TILE_HEIGHT, TILE_WIDTH, TILE_HEIGHT);
            }
        }               
    }
}
class Robot implements Constants {
    private RobotState state = RobotState.moving_east;
    private int row = TILE_HEIGHT;
    private int col = TILE_WIDTH;
    private int mapX = 1;
    private int mapY = 1;
    private Map map;
    int nextRowCheck = 1;
    int nextColCheck = 2;
    public Robot(Map m) {
        map = m;
    }
    public int getRow() {
        return mapY;
    }
    public int getCol() {
        return mapX;
    }
    private boolean needsNewInstruction(){
        int newRow = row;
        int newCol = col;
        if(state == RobotState.moving_north) newRow -= PIXEL_STEPS;
        if(state == RobotState.moving_south) newRow += PIXEL_STEPS;
        if(state == RobotState.moving_east) newCol += PIXEL_STEPS;
        if(state == RobotState.moving_west) newCol -= PIXEL_STEPS;
        if((newRow / TILE_HEIGHT) != mapY) return true;
        if((newCol / TILE_WIDTH) != mapX) return true; 
        return false;
    }

    public void draw(Graphics g) {
        Color c = g.getColor();
        g.setColor(Color.GREEN);
        g.fillRect(col, row, TILE_WIDTH, TILE_HEIGHT);
        g.setColor(c);
    }
    public void update() {
        System.out.println("UPDATE [" + row + "][" + col + "] = [" + (row / TILE_HEIGHT) + "][" + (col / TILE_WIDTH) + "]");

        if(needsNewInstruction()) {
            System.out.println("NEEDS NEW INSTRUCTION [" + row + "][" + col + "] = [" + (row / TILE_HEIGHT) + "][" + (col / TILE_WIDTH) + "]");
            mapX = nextColCheck;
            mapY = nextRowCheck;
            System.out.println("UPDATED MAP REFERENCE [" + mapY + "][" + mapX  + "]");
            row = mapY * TILE_HEIGHT;
            col = mapX * TILE_WIDTH;
            System.out.println("UPDATED PIXEL REFERENCE [" + row + "][" + col  + "]");
            RobotInstruction instruction = map.getNextInstruction(this);
            if(instruction == RobotInstruction.NORTH) {
                state = RobotState.moving_north;
                nextRowCheck = mapY - 1;
            }
            if(instruction == RobotInstruction.SOUTH) {
                state = RobotState.moving_south;
                nextRowCheck = mapY + 1;
            }
            if(instruction == RobotInstruction.EAST) {
                state = RobotState.moving_east;
                nextColCheck = mapX + 1;
            }
            if(instruction == RobotInstruction.WEST) {
                state = RobotState.moving_west;
                nextColCheck = mapX - 1;
            }
        }
        move();
    }
    public void move() {
        if(state == RobotState.moving_north) row -= PIXEL_STEPS;
        if(state == RobotState.moving_south) row += PIXEL_STEPS;
        if(state == RobotState.moving_east) col += PIXEL_STEPS;
        if(state == RobotState.moving_west) col -= PIXEL_STEPS;
    }
}
class Map implements Constants {
    int[][] map = new int[][] {
            {1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1},
            {1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
            {1, 1, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
            {1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
            {1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
            {1, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
            {1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
            {1, 0, 1, 1, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
            {1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
            {1, 1, 1, 1, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
            {1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
            {1, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
            {1, 0, 1, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
            {1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},           
            {1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1}
    };  
    public Map() {
    }
    public RobotInstruction getNextInstruction(Robot robot) {
        int row = robot.getRow();
        int col = robot.getCol();
        System.out.println("GET NEXT INSTRUCTION FOR [" + row + "][" + col + "]");
        if(map[row][col + 1] == 0) return RobotInstruction.EAST;
        if(map[row + 1][col] == 0) return RobotInstruction.SOUTH;
        if(map[row - 1][col] == 0) return RobotInstruction.NORTH;
        if(map[row][col - 1] == 0) return RobotInstruction.WEST;
        return null;
    }
    public void draw(Graphics g) {
        Color color = g.getColor();
        for(int r = 0; r < NUM_TILE_ROWS; r++) {
            for(int c = 0; c < NUM_TILE_COLS; c++) {
                g.setColor(map[r][c] == 0 ? Color.CYAN : Color.RED);
                g.fillRect(c * TILE_WIDTH, r * TILE_HEIGHT, TILE_WIDTH, TILE_HEIGHT);
            }
        }
        g.setColor(color);
    }
}

这是一个如何用方向填充导航数组的示例。上面的代码不使用下面的代码,所以你必须自己做…

public class Maze {
    private static final char E = 'E';   // Ending position
    private static final char X = 'X';   // Wall
    private static final char O = ' ';   // Space
    private static final char L = 'L';   // Left
    private static final char R = 'R';   // Right
    private static final char U = 'U';   // Up
    private static final char D = 'D';   // Down
    private static final char FALSE = '0';   // Not accessible
    private static final char TRUE = '1';    // Is accessible
    private static final Node END_NODE = new Node(4, 4);
    private static final int[] ROW_DIRECTIONS = {-1, 1,  0, 0};  
    private static final int[] COL_DIRECTIONS = { 0, 0, -1, 1};
    private static final char[][] OPPOSITES = new char[][] {{O, D, O},{R, O, L},{O, U, O}};
    public static void main(String[] args) {
        char[][] maze = new char[][] { 
            {X, X, X, X, X, X},
            {X, O, O, X, O, X},
            {X, O, X, X, O, X},
            {X, O, O, O, X, X},
            {X, X, O, X, O, X},
            {X, O, O, O, O, X},
            {X, O, X, X, O, X},
            {X, X, X, X, X, X}};
        // PLOT THE DESTINATION CELL AND ADD IT TO LIST
        List<Node> nodes = new ArrayList<Node>();
        nodes.add(END_NODE);
        maze[END_NODE.row][END_NODE.col] = E;
        // PRINT THE MAZE BEFORE ANY CALCULATIONS
        printMaze(maze);
        // SOLVE THE MAZE
        fillMaze(maze, nodes);
        printMaze(maze);
        // CONVERT MAZE TO AN ADJACENCY MATRIX
        compileMaze(maze);
        printMaze(maze);
    }
    /**
     * The parallel arrays define all four directions radiating from
     * the dequeued node's location. 
     * 
     * Each node will have up to four neighboring cells; some of these
     * cells are accessible, some are not. 
     * 
     * If a neighboring cell is accessible, we encode it with a directional
     * code that calculates the direction we must take should we want to 
     * navigate to the dequeued node's location from this neighboring cell.
     * 
     * Once encoded into our maze, this neighboring cell is itself queued 
     * up as a node so that recursively, we can encode the entire maze.
     */
    public static final void fillMaze(char[][] maze, List<Node> nodes) {
        // dequeue our first node
        Node destination = nodes.get(0);
        nodes.remove(destination);
        // examine all four neighboring cells for this dequeued node
        for(int index = 0; index < ROW_DIRECTIONS.length; index++) {
            int rowIndex = destination.row + ROW_DIRECTIONS[index];
            int colIndex = destination.col + COL_DIRECTIONS[index];
            // if this neighboring cell is accessible, encode it and add it
            // to the queue
            if(maze[rowIndex][colIndex] == O) {
                maze[rowIndex][colIndex] = getOppositeDirection(ROW_DIRECTIONS[index], COL_DIRECTIONS[index]);
                nodes.add(new Node(rowIndex, colIndex));
            }
        }
        // if our queue is not empty, call this method again recursively 
        // so we can fill entire maze with directional codes
        if(nodes.size() > 0) {
            fillMaze(maze, nodes);
        }
    }
    /**
     * Converts the maze to an adjacency matrix. 
     */
    private static void compileMaze(char[][] maze) {
        for(int r = 0; r < maze.length; r++) {
            for(int c = 0; c < maze[0].length; c++) {
                if(maze[r][c] == X || maze[r][c] == O) {
                    maze[r][c] = FALSE;
                }
                else {
                    maze[r][c] = TRUE;
                }
            }
        }
    }
    /**
     * prints the specified two dimensional array 
     */
    private static final void printMaze(char[][] maze) {
        System.out.println("====================================");
        for(int r = 0; r < maze.length; r++) {
            for(int c = 0; c < maze[0].length; c++) {
                System.out.print(maze[r][c] + "  ");
            }
            System.out.print("n");
        }
        System.out.println("====================================");
    }
    /**
     * Simply returns the opposite direction from those specified 
     * by our parallel direction arrays in method fillMaze. 
     * 
     * coordinate 1, 1 is the center of the char[][] array and 
     * applying the specified row and col offsets, we return the
     * correct code (opposite direction)
     */
    private static final char getOppositeDirection(int row, int col) {
         return OPPOSITES[1 + row][1 + col];
    }
}
class Node {
    int row;
    int col;
    public Node(int rowIndex, int colIndex) {
        row = rowIndex;
        col = colIndex;
    }
}

相关内容

  • 没有找到相关文章

最新更新