How to implement availability display?

I have a requirement to display the availability of various assets on a timeline.

My initial thoughts were to utilise a gantt chart but then I realised that this would quickly result in a huge mess vertically as some assets will flit in and out of availability.

The end goal is a control that has a timeline along the X axis, assets along the Y and various boxes/bars indicating the assets' availability.

Would anyone know of an open source WinForms control with this functionality or would anyone know the name of this sort of chart such that I can do some more research and implement one myself?