public MainWindowViewModel(Dispatcher dispatcher)
        {
            _dispatcher = dispatcher;

            TwoAxesViewModel   = new TwoAxesViewModel(_innerAxisRotation, _outerAxisRotation);
            InnerAxisViewModel = new AxisViewModel(_innerAxisSimulator)
            {
                Title = "Inner Axis"
            };
            OuterAxisViewModel = new AxisViewModel(_outerAxisSimulator)
            {
                Title = "Outer Axis"
            };
            ChartViewModel = new ChartViewModel();

            _timer = new Timer(state => Poll(), null, TimeSpan.Zero, _pollingTime);
        }