For tasks like controlling motors or reading sensors, use a microcontroller.
Nodes for communicating with Arduinos (or other microcontrollers) running the Firmata Protocol are shipping with vvvv. Reference the VL.IO.Firmata package via the Node Browser and see its helppatches in the Help Browser.
Want to use plain C# to write code for your microcontrollers? Try the nanoFramework which allows you to write C# with a reduced set of .NET libraries that run on hardware like ESPs and more.
Want to use full C#/.NET on a microcontroller? Try Meadow.