在matlab中，基于角度优先的围捕策略，实现6机器人围捕3目标的任务，保证目标一直在机器人视角内，以角度设置围捕标志。在目标被围捕后，围捕该目标的机器人组留下一个机器人看守，其余机器人继续围捕尚未完成围捕的目标。绘制出围捕过程

这个任务可以使用MATLAB中的Robotics System Toolbox来实现。我们可以使用ROS（Robot Operating System）来模拟机器人和目标，并在MATLAB中控制机器人和目标的运动。

首先，我们需要定义机器人和目标的初始位置，以及围捕半径和视角。然后，我们可以创建ROS节点并将机器人和目标添加到ROS网络中。

接下来，我们可以使用ROS订阅器来获取机器人和目标的位置，并计算机器人到目标的距离和方位角。如果目标在机器人的视角内并且距离小于围捕半径，则机器人将开始围捕目标。

一旦机器人围捕了目标，围捕该目标的机器人组将有一个机器人留下来看守，其余机器人将继续围捕尚未完成围捕的目标。我们可以使用一个列表来跟踪哪些目标被围捕，哪些机器人正在围捕每个目标，并且哪些机器人留下来看守。

最后，我们可以使用MATLAB绘图工具箱来绘制机器人和目标的运动轨迹，以及围捕过程。

以下是一个简单的MATLAB代码示例，演示了如何实现这个任务：

% Define initial positions of robots and targets
robot_pos = [0 0; 1 1; -1 -1; 2 -2; -2 2; 3 3];
target_pos = [-1 0; 2 1; -3 -2];

% Define capture radius and field of view angle
capture_radius = 0.5;
fov_angle = pi/2;

% Create ROS node
rosinit

% Add robots to ROS network
for i = 1:size(robot_pos, 1)
    ros_robot(i) = rosdevice('/robot' + string(i), 'ROSNodeName', 'robot' + string(i));
    ros_robot(i).addPublisher('/robot' + string(i) + '/cmd_vel', 'geometry_msgs/Twist');
    ros_robot(i).addSubscriber('/robot' + string(i) + '/pose', 'geometry_msgs/Pose');
end

% Add targets to ROS network
for i = 1:size(target_pos, 1)
    ros_target(i) = rosdevice('/target' + string(i), 'ROSNodeName', 'target' + string(i));
    ros_target(i).addPublisher('/target' + string(i) + '/cmd_vel', 'geometry_msgs/Twist');
    ros_target(i).addSubscriber('/target' + string(i) + '/pose', 'geometry_msgs/Pose');
end

% Initialize list of captured targets and capturing robots
captured_targets = zeros(size(target_pos, 1), 1);
capturing_robots = zeros(size(target_pos, 1), 1);

% Define main loop
while ~all(captured_targets)
    % Get current robot and target positions
    robot_pos_list = zeros(size(robot_pos));
    target_pos_list = zeros(size(target_pos));
    for i = 1:size(robot_pos, 1)
        robot_pos_list(i,:) = ros_robot(i).LatestMessage.Position;
    end
    for i = 1:size(target_pos, 1)
        target_pos_list(i,:) = ros_target(i).LatestMessage.Position;
    end
    
    % Check which targets are not yet captured
    uncaptured_targets = find(~captured_targets);
    
    % Loop over each robot
    for i = 1:size(robot_pos, 1)
        % Calculate distances and angles to each target
        dist = vecnorm(robot_pos_list(i,:) - target_pos_list, 2, 2);
        angle = atan2(target_pos_list(:,2) - robot_pos_list(i,2), target_pos_list(:,1) - robot_pos_list(i,1));
        
        % Check if any targets are in robot's field of view and within capture radius
        in_fov = abs(angle - robot_pos_list(i,3)) < fov_angle/2;
        in_capture_radius = dist < capture_radius;
        valid_targets = uncaptured_targets(in_fov & in_capture_radius);
        
        % If there are valid targets, select the closest one and start capturing it
        if ~isempty(valid_targets)
            closest_target = valid_targets(vecnorm(target_pos_list(valid_targets,:) - robot_pos_list(i,1:2), 2, 2) == min(vecnorm(target_pos_list(valid_targets,:) - robot_pos_list(i,1:2), 2, 2)));
            capturing_robots(closest_target) = [capturing_robots(closest_target); i];
        end
    end
    
    % Loop over each target
    for i = 1:size(target_pos, 1)
        % If target is being captured, check if enough robots are present
        if ~isempty(capturing_robots(i))
            if length(capturing_robots(i,:)) == 1
                % If only one robot is capturing target, leave a robot to guard it and continue capturing
                guarding_robot = capturing_robots(i);
                capturing_robots(i) = [];
                capturing_robots(i,:) = guarding_robot;
            else
                % If multiple robots are capturing target, continue capturing
                continue
            end
        end
        
        % If target is not being captured, move target randomly
        msg = rosmessage('geometry_msgs/Twist');
        msg.Linear.X = rand()*2 - 1;
        msg.Angular.Z = rand()*2*pi - pi;
        ros_target(i).send(msg);
    end
    
    % Loop over each robot
    for i = 1:size(robot_pos, 1)
        % If robot is capturing a target, move towards it
        capturing_target = find(capturing_robots == i);
        if ~isempty(capturing_target)
            msg = rosmessage('geometry_msgs/Twist');
            msg.Linear.X = capture_radius/2; % move at half the capture radius per second
            angle_to_target = atan2(target_pos_list(capturing_target,2) - robot_pos_list(i,2), target_pos_list(capturing_target,1) - robot_pos_list(i,1));
            msg.Angular.Z = angle_to_target - robot_pos_list(i,3);
            ros_robot(i).send(msg);
        else
            % If robot is not capturing a target, move randomly
            msg = rosmessage('geometry_msgs/Twist');
            msg.Linear.X = rand()*2 - 1;
            msg.Angular.Z = rand()*2*pi - pi;
            ros_robot(i).send(msg);
        end
    end
    
    % Check if any targets have been captured
    for i = 1:size(capturing_robots, 1)
        if length(capturing_robots(i,:)) >= 2
            captured_targets(i) = 1;
        end
    end
    
    % Pause for visualization
    pause(0.1)
end

% Plot robot and target trajectories
figure
hold on
for i = 1:size(robot_pos, 1)
    plot(ros_robot(i).PoseHistory(:,1), ros_robot(i).PoseHistory(:,2), 'LineWidth', 2)
end
for i = 1:size(target_pos, 1)
    plot(ros_target(i).PoseHistory(:,1), ros_target(i).PoseHistory(:,2), 'LineWidth', 2)
end
axis equal