RRT代码matlab
时间: 2023-09-27 22:06:09 浏览: 79
Sure! Here's a simple implementation of the RRT (Rapidly-Exploring Random Trees) algorithm in Matlab:
```matlab
classdef RRT
properties
map % occupancy map
start % start position
goal % goal position
tree % RRT tree
stepSize % step size for tree expansion
end
methods
function obj = RRT(map, start, goal, stepSize)
obj.map = map;
obj.start = start;
obj.goal = goal;
obj.tree = [start];
obj.stepSize = stepSize;
end
function path = plan(obj, maxIterations)
for i = 1:maxIterations
qRand = obj.generateRandomConfig();
qNearIdx = obj.findNearestNeighbor(qRand);
qNear = obj.tree(qNearIdx,:);
qNew = obj.extend(qNear, qRand);
if obj.isCollisionFree(qNear, qNew)
obj.tree = [obj.tree; qNew];
if norm(qNew - obj.goal) < obj.stepSize
path = [obj.tree; obj.goal];
return;
end
end
end
path = [];
end
function qRand = generateRandomConfig(obj)
xrange = size(obj.map, 2);
yrange = size(obj.map, 1);
qRand = [randi(xrange), randi(yrange)];
end
function qNearIdx = findNearestNeighbor(obj, qRand)
distances = vecnorm(obj.tree - qRand, 2, 2);
[~, qNearIdx] = min(distances);
end
function qNew = extend(obj, qNear, qRand)
direction = (qRand - qNear) / norm(qRand - qNear);
qNew = qNear + obj.stepSize * direction;
end
function collisionFree = isCollisionFree(obj, qNear, qNew)
indices = round(linspace(qNear(2), qNew(2), 10));
for idx = round(linspace(qNear(1), qNew(1), 10))
if obj.map(indices(idx), idx) == 1
collisionFree = false;
return;
end
end
collisionFree = true;
end
end
end
```
You can use the `RRT` class to plan a path from the start position to the goal position. Here's an example of how to use it:
```matlab
% Create a map (occupancy grid)
map = zeros(100, 100);
map(30:40, 30:60) = 1;
% Set the start and goal positions
start = [10, 10];
goal = [90, 90];
% Create an instance of the RRT planner
rrt = RRT(map, start, goal, 5);
% Plan the path
path = rrt.plan(1000);
% Plot the map and path
imagesc(map);
colormap(flipud(gray));
hold on;
plot(rrt.tree(:,1), rrt.tree(:,2), 'b.');
plot(path(:,1), path(:,2), 'r', 'LineWidth', 2);
plot(start(1), start(2), 'go', 'MarkerSize', 10);
plot(goal(1), goal(2), 'ro', 'MarkerSize', 10);
hold off;
```
This code creates a simple occupancy grid map with obstacles, sets the start and goal positions, creates an instance of the RRT planner, plans a path using 1000 iterations, and plots the map and path. You can adjust the map, start, goal, and step size values to suit your specific requirements.
Note that this implementation assumes a 2D grid map and uses Euclidean distance for nearest neighbor calculations.
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