It sounds like you want a very binary controller. If a velocity is larger than a threshold do one thing, if not do another. If that is right, check out the switch block
![Switch.PNG](https://www.mathworks.com/matlabcentral/answers/uploaded_files/230340/Switch.png)
This block outputs the top input when the middle input satisfies a constraint. Otherwise it passes the bottom input. With velocity as your middle input you can use the other two to turn on and off your other blocks.