gusucode.com > Mobile Robotics Simulation Toolbox > examples/matlab/kinematics/mrsDiffDriveDiscrete.m
%% EXAMPLE: Differential Drive discrete simulation % Copyright 2018 The MathWorks, Inc. %% Define Robot R = 0.1; % Wheel radius [m] L = 0.5; % Wheelbase [m] dd = DifferentialDrive(R,L); %% Simulation parameters sampleTime = 0.01; % Sample time [s] initPose = [0;0;pi/4]; % Initial pose (x y theta) % Initialize time, input, and pose arrays tVec = 0:sampleTime:10; % Time array vRef = 0.2*ones(size(tVec)); % Reference linear speed wRef = zeros(size(tVec)); % Reference angular speed wRef(tVec < 5) = -0.5; wRef(tVec >=5) = 0.5; pose = zeros(3,numel(tVec)); % Pose matrix pose(:,1) = initPose; %% Simulation loop for idx = 2:numel(tVec) % Solve inverse kinematics to find wheel speeds [wL,wR] = inverseKinematics(dd,vRef(idx-1),wRef(idx-1)); % Compute the velocities [v,w] = forwardKinematics(dd,wL,wR); velB = [v;0;w]; % Body velocities [vx;vy;w] vel = bodyToWorld(velB,pose(:,idx-1)); % Convert from body to world % Perform forward discrete integration step pose(:,idx) = pose(:,idx-1) + vel*sampleTime; end %% Display results close all figure hold on plot(pose(1,1),pose(2,1),'ro', ... pose(1,end),pose(2,end),'go', ... pose(1,:),pose(2,:),'b-'); axis equal title('Vehicle Trajectory'); xlabel('X [m]') ylabel('Y [m]') legend('Start','End','Trajectory')