edit this matlab code: max $50

%% this code is suppose to is be able to detect an obstacle, stop in front of obstacle, go pass by the obstacle if ismember([login to view URL], rostopic('list')) laser_sub = rossubscriber('/scan'); end if ismember([login to view URL], rostopic('list')) velocity_pub = rospublisher([login to view URL],'geometry_msgs/Twist'); % velocity_sub = rossubscriber('cmd_vel', 'geometry_msgs/Twist'); end velocity_msg = rosmessage(velocity_pub); % Set some parameters that will be used in the processing loop. % You can modify these values for different behavior. spinVelocity = 0.6; % Angular velocity (rad/s) forwardVelocity = 0.2; % Linear velocity (m/s) backwardVelocity = -0.6; % Linear velocity (reverse) (m/s) distanceThreshold = .6; % Distance threshold (m) for turning % Run a loop to move the robot forward and compute the closest obstacles %to % the robot. When an obstacle is within the limits of the %distanceThreshold, % the robot turns. This loop stops after 20 seconds of run time. % CTRL+C (or Control+C on the Mac) also stops this loop. tic; while toc < 20 % Collect information from laser scan scan_data = receive(laser_sub,1); plot(scan_data); data = readCartesian(scan_data); x = data(:,1); y = data(:,2); % Compute distance of the closest obstacle dist = sqrt(x.^2 + y.^2); minDist = min(dist); % Command robot action scan_data = receive(laser_sub); if minDist < distanceThreshold % If close to obstacle, back up slightly and spin velocity_msg.Linear.X = backwardVelocity; velocity_msg.Angular.Z = spinVelocity; velocity_msg.Linear.X=forwardVelocity; velocity_msg.Angular.Z = -spinVelocity; velocity_msg.Linear.X=forwardVelocity; else % Continue on forward path velocity_msg.Linear.X = forwardVelocity; velocity_msg.Angular.Z = 0; end send(velocity_pub, velocity_msg); end % let TurtleBot stop before disconnect from it velocity_msg.Angular.Z = 0.0; velocity_msg.Linear.X = 0.0; send(velocity_pub, velocity_msg);