def turn(vx=1.0, vy=0.0, wz=0.5, t=16):
    """Generate a trajectory where the robot takes a right turn."""
    time_points = range(t)
    speed_points = (
        # One side
        (0, 0, 0, 0),
        (vx, 0, 0, 0),
        (vx, 0, 0, 0),
        (0, 0, 0, wz),
        (0, 0, 0, wz),
        (0, 0, 0, wz),
        (vx, 0, 0, 0),
        (vx, 0, 0, 0),
        # Other side
        (vx, 0, 0, 0),
        (vx, 0, 0, 0),
        (vx, 0, 0, 0),
        (vx, 0, 0, 0),
        (vx, 0, 0, 0),
        (vx, 0, 0, 0),
        (vx, 0, 0, 0),
        (vx, 0, 0, 0))
    return time_points, speed_points