Esempio n. 1
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def main():
    model = ThreeInputModel(L1, L2, LB, UB, output_idx=[0, 1])

    vd = np.array([0, 0])
    pd = np.array([1, 1])
    K = np.eye(2)
    dt = 0.1
    q0 = np.zeros(3)

    q = clik(model, K, dt, vd, pd, q0)

    print(q)
    print(model.forward(q))
Esempio n. 2
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def main():
    N = int(DURATION / DT) + 1

    model = ThreeInputModel(L1, L2, VEL_LIM, acc_lim=ACC_LIM, output_idx=[0, 1])
    pendulum = InvertedPendulum(L_PEND, M_PEND, G)

    W = 0.1 * np.eye(model.ni)

    # we don't want position feedback on x, only y
    K = np.array([[0, 0], [0, 1]])
    controller = BaselineController2(model, W, K, DT, VEL_LIM, acc_lim=ACC_LIM)

    Q = np.eye(4)
    R = 0.01*np.eye(1)

    # LQR controller for the pendulum
    A = pendulum.A
    B = pendulum.B.reshape((4, 1))
    Q = np.eye(4)
    R = 0.01*np.eye(1)
    K, _, _ = control.lqr(A, B, Q, R)
    K = K.flatten()

    ts = np.array([i * DT for i in range(N)])
    qs = np.zeros((N, model.ni))
    dqs = np.zeros((N, model.ni))
    us = np.zeros((N, model.ni))
    ps = np.zeros((N, model.no))
    vs = np.zeros((N, model.no))
    fs = np.zeros((N, 2))

    q0 = np.array([0, np.pi/4.0, -np.pi/4.0])
    p0 = model.forward(q0)

    q = q0
    p = p0
    dq = np.zeros(model.ni)
    v = np.zeros(model.no)
    qs[0, :] = q0
    ps[0, :] = p0

    # pendulum state
    X = np.zeros((N, 4))
    X[0, :] = np.array([0.3, 0, 0, 0])

    # real time plotting
    robot_renderer = ThreeInputRenderer(model, q0, render_path=False)
    pendulum_renderer = PendulumRenderer(pendulum, X[0, :], p0)
    plotter = RealtimePlotter([robot_renderer, pendulum_renderer])
    plotter.start()

    for i in range(N - 1):
        t = ts[i]

        u_pendulum = -K @ X[i, :]

        # controller
        pd = p0
        vd = np.zeros(2)
        vd[0] = v[0] + DT * u_pendulum
        u = controller.solve(q, dq, pd, vd)

        # step the model
        q, dq = model.step(q, u, DT, dq_last=dq)
        p = model.forward(q)
        v = model.jacobian(q).dot(dq)

        x_acc = (v[0] - vs[i, 0]) / DT
        fs[i, :] = pendulum.calc_force(X[i, :], x_acc)
        X[i+1, :] = pendulum.step(X[i, :], x_acc, DT)

        angle = X[i, 0]
        angle_est = np.arctan2(fs[i, 0], -fs[i, 1])

        # record
        us[i, :] = u

        dqs[i+1, :] = dq
        qs[i+1, :] = q
        ps[i+1, :] = p
        vs[i+1, :] = v

        robot_renderer.set_state(q)
        pendulum_renderer.set_state(X[i+1, :], p)
        plotter.update()

    plotter.done()

    plt.figure()
    plt.plot(ts, ps[:, 0],  label='$x$', color='b')
    plt.plot(ts, ps[:, 1],  label='$y$', color='r')
    plt.grid()
    plt.legend()
    plt.xlabel('Time (s)')
    plt.ylabel('Position')
    plt.title('End effector position')

    plt.figure()
    plt.plot(ts, dqs[:, 0], label='$\\dot{q}_x$')
    plt.plot(ts, dqs[:, 1], label='$\\dot{q}_1$')
    plt.plot(ts, dqs[:, 2], label='$\\dot{q}_2$')
    plt.grid()
    plt.legend()
    plt.title('Commanded joint velocity')
    plt.xlabel('Time (s)')
    plt.ylabel('Velocity')

    plt.figure()
    plt.plot(ts, qs[:, 0], label='$q_x$')
    plt.plot(ts, qs[:, 1], label='$q_1$')
    plt.plot(ts, qs[:, 2], label='$q_2$')
    plt.grid()
    plt.legend()
    plt.title('Joint positions')
    plt.xlabel('Time (s)')
    plt.ylabel('Joint positions')

    plt.figure()
    plt.plot(ts, X[:, 0])
    plt.grid()
    plt.title('Pendulum Angle')
    plt.xlabel('Time (s)')
    plt.ylabel('Angle (rad)')

    plt.figure()
    plt.plot(ts[:-1], fs[:-1, 0], label='fx')
    plt.plot(ts[:-1], fs[:-1, 1], label='fy')
    plt.grid()
    plt.title('EE Force')
    plt.xlabel('Time (s)')
    plt.ylabel('Force (N)')

    plt.show()
Esempio n. 3
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def main():
    N = int(DURATION / DT) + 1

    model = ThreeInputModel(L1, L2, VEL_LIM, acc_lim=ACC_LIM, output_idx=[0, 1])

    Q = np.eye(model.no)
    R = np.eye(model.ni) * 0.01
    mpc = MPC(model, DT, Q, R, VEL_LIM, ACC_LIM)

    ts = DT * np.arange(N)
    qs = np.zeros((N, model.ni))
    dqs = np.zeros((N, model.ni))
    us = np.zeros((N, model.ni))
    ps = np.zeros((N, model.no))
    vs = np.zeros((N, model.no))
    pds = np.zeros((N, model.no))

    q0 = np.array([0, np.pi/4.0, -np.pi/4.0])
    p0 = model.forward(q0)

    # reference trajectory
    timescaling = QuinticTimeScaling(DURATION)
    points = np.array([p0, p0 + [1, 1], p0 + [2, -1], p0 + [3, 0]])
    trajectory = CubicBezier(points, timescaling, DURATION)

    # obstacles
    # obs = Wall(x=2.5)
    # obs = Circle(c=np.array([3.0, 1.5]), r=1)

    q = q0
    p = p0
    dq = np.zeros(model.ni)
    qs[0, :] = q0
    ps[0, :] = p0
    pds[0, :] = p0

    robot_renderer = ThreeInputRenderer(model, q0)
    trajectory_renderer = TrajectoryRenderer(trajectory, ts)
    plotter = RealtimePlotter([robot_renderer, trajectory_renderer])
    plotter.start()

    for i in range(N - 1):
        # MPC
        # The +1 ts[i+1] is because we want to generate a u[i] such that
        # p[i+1] = FK(q[i+1]) = pd[i+1]
        n = min(NUM_HORIZON, N - 1 - i)
        pd, _, _ = trajectory.sample(ts[i+1:i+1+n], flatten=True)
        u = mpc.solve(q, dq, pd, n)

        q, dq = model.step(q, u, DT, dq_last=dq)
        p = model.forward(q)
        v = model.jacobian(q).dot(dq)

        # record
        us[i, :] = u

        dqs[i+1, :] = dq
        qs[i+1, :] = q
        ps[i+1, :] = p
        pds[i+1, :] = pd[:model.no]
        vs[i+1, :] = v

        robot_renderer.set_state(q)
        plotter.update()
    plotter.done()

    xe = pds[1:, 0] - ps[1:, 0]
    ye = pds[1:, 1] - ps[1:, 1]
    print('RMSE(x) = {}'.format(rms(xe)))
    print('RMSE(y) = {}'.format(rms(ye)))

    plt.figure()
    plt.plot(ts, pds[:, 0], label='$x_d$', color='b', linestyle='--')
    plt.plot(ts, pds[:, 1], label='$y_d$', color='r', linestyle='--')
    plt.plot(ts, ps[:, 0],  label='$x$', color='b')
    plt.plot(ts, ps[:, 1],  label='$y$', color='r')
    plt.grid()
    plt.legend()
    plt.xlabel('Time (s)')
    plt.ylabel('Position')
    plt.title('End effector position')

    plt.figure()
    plt.plot(ts, dqs[:, 0], label='$\\dot{q}_x$')
    plt.plot(ts, dqs[:, 1], label='$\\dot{q}_1$')
    plt.plot(ts, dqs[:, 2], label='$\\dot{q}_2$')
    plt.grid()
    plt.legend()
    plt.title('Actual joint velocity')
    plt.xlabel('Time (s)')
    plt.ylabel('Velocity')

    plt.figure()
    plt.plot(ts, us[:, 0], label='$u_x$')
    plt.plot(ts, us[:, 1], label='$u_1$')
    plt.plot(ts, us[:, 2], label='$u_2$')
    plt.grid()
    plt.legend()
    plt.title('Commanded joint velocity')
    plt.xlabel('Time (s)')
    plt.ylabel('Velocity')

    plt.show()
Esempio n. 4
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def main():
    N = int(DURATION / DT) + 1

    model = ThreeInputModel(L1, L2, VEL_LIM, acc_lim=ACC_LIM, output_idx=[0, 1])

    W = 0.1 * np.eye(model.ni)
    Kp = np.eye(model.no)
    Kv = 0.1 * np.eye(model.no)
    controller = AccelerationController(model, W, Kp, Kv, DT, VEL_LIM, ACC_LIM)

    ts = np.array([i * DT for i in range(N)])
    qs = np.zeros((N, model.ni))
    dqs = np.zeros((N, model.ni))
    us = np.zeros((N, model.ni))
    ps = np.zeros((N, model.no))
    vs = np.zeros((N, model.no))
    pds = np.zeros((N, model.no))
    dq_cmds = np.zeros((N, model.ni))

    q0 = np.array([0, np.pi/4.0, -np.pi/4.0])
    p0 = model.forward(q0)

    # reference trajectory
    timescaling = QuinticTimeScaling(DURATION)
    trajectory = PointToPoint(p0, p0 + [1, 0], timescaling, DURATION)

    # pref, vref, aref = trajectory.sample(ts)
    # plt.figure()
    # plt.plot(ts, pref[:, 0], label='$p$')
    # plt.plot(ts, vref[:, 0], label='$v$')
    # plt.plot(ts, aref[:, 0], label='$a$')
    # plt.grid()
    # plt.legend()
    # plt.title('EE reference trajectory')
    # plt.xlabel('Time (s)')
    # plt.ylabel('Reference signal')
    # plt.show()

    q = q0
    p = p0
    dq = np.zeros(model.ni)
    qs[0, :] = q0
    ps[0, :] = p0
    pds[0, :] = p0

    robot_renderer = ThreeInputRenderer(model, q0)
    trajectory_renderer = TrajectoryRenderer(trajectory, ts)
    plotter = RealtimePlotter([robot_renderer, trajectory_renderer])
    plotter.start()

    for i in range(N - 1):

        t = ts[i]

        # controller
        pd, vd, ad = trajectory.sample(t, flatten=True)
        u = controller.solve(q, dq, pd, vd, ad)
        dq_cmd = dq + DT * u

        # step the model
        q, dq = model.step(q, dq_cmd, DT, dq_last=dq)
        p = model.forward(q)
        v = model.jacobian(q).dot(dq)

        # record
        us[i, :] = u
        dq_cmds[i, :] = dq_cmd

        dqs[i+1, :] = dq
        qs[i+1, :] = q
        ps[i+1, :] = p
        pds[i+1, :] = pd[:model.no]
        vs[i+1, :] = v

        robot_renderer.set_state(q)
        plotter.update()
    plotter.done()

    xe = pds[1:, 0] - ps[1:, 0]
    ye = pds[1:, 1] - ps[1:, 1]
    print('RMSE(x) = {}'.format(rms(xe)))
    print('RMSE(y) = {}'.format(rms(ye)))

    plt.figure()
    plt.plot(ts, pds[:, 0], label='$x_d$', color='b', linestyle='--')
    plt.plot(ts, pds[:, 1], label='$y_d$', color='r', linestyle='--')
    plt.plot(ts, ps[:, 0],  label='$x$', color='b')
    plt.plot(ts, ps[:, 1],  label='$y$', color='r')
    plt.grid()
    plt.legend()
    plt.xlabel('Time (s)')
    plt.ylabel('Position')
    plt.title('End effector position')

    plt.figure()
    plt.plot(ts, dqs[:, 0], label='$\\dot{q}_x$')
    plt.plot(ts, dqs[:, 1], label='$\\dot{q}_1$')
    plt.plot(ts, dqs[:, 2], label='$\\dot{q}_2$')
    plt.grid()
    plt.legend()
    plt.title('Joint velocity')
    plt.xlabel('Time (s)')
    plt.ylabel('Velocity')

    plt.figure()
    plt.plot(ts, dq_cmds[:, 0], label='$\\dot{q}_x$')
    plt.plot(ts, dq_cmds[:, 1], label='$\\dot{q}_1$')
    plt.plot(ts, dq_cmds[:, 2], label='$\\dot{q}_2$')
    plt.grid()
    plt.legend()
    plt.title('Commanded Joint Velocity')
    plt.xlabel('Time (s)')
    plt.ylabel('Velocity')

    plt.figure()
    plt.plot(ts, us[:, 0], label='$u_x$')
    plt.plot(ts, us[:, 1], label='$u_1$')
    plt.plot(ts, us[:, 2], label='$u_2$')
    plt.grid()
    plt.legend()
    plt.title('Commanded joint acceleration')
    plt.xlabel('Time (s)')
    plt.ylabel('Acceleration')

    plt.figure()
    plt.plot(ts, qs[:, 0], label='$q_x$')
    plt.plot(ts, qs[:, 1], label='$q_1$')
    plt.plot(ts, qs[:, 2], label='$q_2$')
    plt.grid()
    plt.legend()
    plt.title('Joint positions')
    plt.xlabel('Time (s)')
    plt.ylabel('Joint positions')

    plt.show()